dyno day at pappy's

[chad502ex]

Thanks to Mobile Dyno at Precision Motorpsports for all your expertise today. Both Brian and I really appreciate your help.

Secondly, Thanks Pappy for your warm hospitality to be able to dyno at your place today, and for providinng fodd and drink for us.

Third, Thanks Pappy (again) for your tools to help me examine my front wheel truck bearing. It was a long 100 mile drive home after I heard my bearings howl when I pulled into his driveway early in the morning,... can't believe I made it home after bearing failure,...


Summary:

weather perfect.
company great.

My day sucked arse.

WPP Racing day was awesome.

Not only did my truck bearings have issues, but my 550 let go on the dyno after ~58hp and 10.000 rpm. no signs of any issues or noise before it went near limit. yes, scattered at 10,000 rpm just over peak. We were just dialed in and making a few pulls for max, when she popped. White smoke cloud out the exhaust pipe, then coolent is the sight glass.

Tommorrow, I'll take her down and take a few pictures.

I'm thinking the cylinder cracked under load (coolant in sight glass after shutdown) and the piston caught an edge, ect,....

Oh well, I'll have it back running soon after I dig deep $$$$

Hopefully, the damage is all top end and not rod or crank.

First engine of mine that let go- oh well it's going to be a nice winter project in the garage,..... :D

[chad502ex]

Both Brians (WPP Racing) and my max pulls for the day.

[chad502ex]

these two runs are comparing my new DASA head to my old NMotion head.

The only difference between these two pulls are the two heads and the cams.

On the lower NMotion head curve I ran a bigger Megacyle X2 cam, and the DASA head was run with smaller Web cam 208 cam.



Wasn't the 60's that I was hoping for, but I was running up for max pulls and the next coulpe would have gotten near 59 for sure

[chad502ex]

and while i was on the dyno i was able to print a comparison between a:

440ex
86 trx250R
88 trx250R
and the 550R


only sounds like a few hp when you talk the difference in hp numbers, but when you see an area under the curve its completely different

[wvspeedfreak]

Man,I left too early and missed the exitement.Sorry about your engine Chad.You were just starting to dial it in when I was there.I would have liked to talked to you a little more but you guys were elbow deep in jetting so I just watched :D

[chad502ex]

It was great see'n ya again.

[wppracing]

It sucked that the engine let go. After 2 hrs of playing carb installer/removers we had it dialed in , Then it went Boom complete with white smoke from the exhaust and air box.
Let us know what it was when you have it apart

[kazpr]

Did the Dasa motor run on the dyno??

[Pappy]

always good to have you guys up for a day of dyno'n:p

sorry i didnt hang out much, as you could see we have our hands full getting the place ready for winter!

[Kilabanshee]

How do you like the Baldwin piston Brian??

Sorry to hear about the 550r Chad!

[wppracing]

Very pleased with it. I have a post with the graphs on it.

[chad502ex]

Originally posted by wppracing
Very pleased with it. I have a post with the graphs on it.

Was talk'in with DASA about the first run on the main being 195 at ~12 a/f, then by the third pull the main being dropped to 170 main still at ~12. In other words, no change in a/f from 195 to 170- huh? Dan also thought that was the sign that I may have cracked my cylinder and started to pull in coolant droplets into the a/f mixture therefore cause me to small the main up from 195 to 170.

I'll post pictures tommorrow.

Still think'n after repair it'll be 60 :D

can't help my addiction to engines...

[kyex40047]

well i guess you have proved what kind of " engine assembler" you are chad, congrats!

[WhiteZee]

^ that was me.

[370kingR]

Sorry to hear your motor popped Chad. At least you have the resources to fixer up. Im sure your antsy to get in there and find out what happened. I bet it was like being kicked in the nuts when she let go. I definetly cringe when the motor starts to get around 10,000 or so on the dyno.

If i wasnt so banged up i would have made the trip. I always enjoy hanging with you motor headz. I wish i could have sent someone down with my bike to see what it does on Matts dyno. I will one day. :(

[chad502ex]

Originally posted by kyex40047
well i guess you have proved what kind of " engine assembler" you are chad, congrats!

well i guess you have proved what kind of "guy you are"

I see you must be a WhiteZee twin based on your signature.

You and Whitezee showing your true colors,....:rolleyes:


quote from Whitezee on .org
retard blowing his motor up is the best news iv heard all week!



Regardless, there is nobody that can predict when an engine is going to let go. Ever watch NHRA Dragsters blow up on the drag strip? Guess you think that those engine builders don't understand either, huh?

Overall, I consider myself fortunate that I've ran my engine for the 2 years of hard riding with the 530 builds and the 550 builds before the new DASA head was installed. In other words, to suggest that this engine wasn't durable is just not understanding all the hard riding that it's been through over the last two years. Metal is metal and metal becomes fatigue over high stress environments. This engine has been producing over 55hp for almost two years now- think it wasn't stressed is just feebleminded.

now all u need is to drop that new DASA pipe on there and make it up to 60 :macho

[chad502ex]

side load on 101mm piston pushing through the cyclinder walls was the failure

too much side load when the engine hit 58 the piston skirts pushed through walls into the water jackets.

piston destroyed.

crank and rod no damage.

all damage contained in head, cylinder, and piston- as if that isn't enough.


I think I found the hp limitation on 550cc with 101mm bore on NMotion jug.

I never saw the this much skirt wear on the 530 as i see on this 101mm, but i never had this much of hp on the 530 either. Really, the rod angle didn't change (still the same stroke) but the force was increased quit a bit.

My ol' 99mm 530 side skirts were alot smaller that the 550 101mm side skirts.

Pictures tonight for your entertainment.

[MAD450r]

I wanted to go, and get my 450r dyno'd so badly. I just couldn't get a ride from 06489 Southington CT to pappy's.


Anyon have a motor similar to mine, and have it dyno'd this weekend. Mine is stock besides hrc cam, internally. I have my sparks exhaust and filter besides that.

Just curious to the ballpark I am in at the rear wheels. Im guessing somewhere near 45, but would like a second opinion.

[jeepnrocks]

probably not 45 hp.. maybe around 40ish??

[Kilabanshee]

Yeah around 40-42 hp with those mods.

[29FTEX]

Originally posted by chad502ex

Overall, I consider myself fortunate that I've ran my engine for the 2 years of hard riding with the 530 builds and the 550 builds before the new DASA head was installed. In other words, to suggest that this engine wasn't durable is just not understanding all the hard riding that it's been through over the last two years. Metal is metal and metal becomes fatigue over high stress environments. This engine has been producing over 55hp for almost two years now- think it wasn't stressed is just feebleminded.

2 years?

Below was posted by you on 2/20/05. So, a little over 8 months total, and not counting all the down time.



Originally posted by chad502ex
fired up the 530r for the first time tonight to wear-in on the dyno either friday night or saturday morning. it sounded really aggressive. i'm real happy it started. if i can just keep the grim reaper away from the new 05' crank bearing, it should be ok- i hope.

chad502ex.com

:D

I know what it's like to crack a cylinder, and it sucks. You're just really lucky that it is all in the top end and not crank and/or head problems.

[kgbg]

I know of stock cylinders making that hp, so do you, so why would a Nmotion not hold up to it?

[kazpr]

Chad must have secretly had a HH piston in that setup. He said they are time bombs :macho

[370kingR]

Chad, werent you pulling something like 41 or so TQ out of the 530? And if i remember correctly, you were making like 58 HP as well out of the 530. So the 550 seems like it took a step backwards from the original 530 setup.

What im really getting at is perhaps something was wrong from pull one because the numbers seem a bit down actually. Not bad, just down a slight bit. Just wondering...

[chad502ex]

Originally posted by 370kingR
Chad, werent you pulling something like 41 or so TQ out of the 530? And if i remember correctly, you were making like 58 HP as well out of the 530. So the 550 seems like it took a step backwards from the original 530 setup.

What im really getting at is perhaps something was wrong from pull one because the numbers seem a bit down actually. Not bad, just down a slight bit. Just wondering...

Yes, Gary. The 58.5 hp was with the sparks pipe on the 530 measured with a load dyno- not the dynojet freewheel dyno. The 530 max hp i believe on the free wheel dyno was 56.

I understand your thought, but honestly it was evident that yesterdays dyno the engine was not running right. the 550 started the first pull yesterday at 55.5 with 195 main and ended the last 57.2 pull at 170 with same main a/f reading. Evident that the engine was not pulling the max with the crack cylinder and coolant droplets screwing with a/f. my point is that if the cylinder had not cracked maybe the hp pulls could have been more ;)

[370kingR]

Yea thats what i think. It started the day with those problems. Hey like someone said, at least its only a cylinder and not the head and or crank. I know that cylinder isnt cheap but it could have been worse.

You gona post some pics of the damage. I saw something about entertainment :chinese:

[chad502ex]

here is the first of your, or shall I say org's entertainment,... :(

All the speculation I read on org about if this is the limitations of the 550, I'd say no it was the cylinder.

That being said, I will say that I've been motivated by something bigger- or shall I say smaller. I think 55-60 on a stock bore is obtainable and by January I hop to be able to prove it. Over 60 on a stock bore i'll just leave that to the expert (DASA), but 55-60 on stock bore will be done right after Christmas.


Anyway, here is the first of the cylinder

[chad502ex]

The other side of the cylinder from the back piston skirt side load.

two cracks on each side..


cylinder side load cracks 4.

[chad502ex]

:(

more disappointment.


piston pulled out smoothly out of cylinder.

Even though I 99% sure that the rod isn't bent, I'm done with it.

Going to throw the stock crank in after splitting the case and going to start again on stock 04/05' stroke and bore with DASA top end, RE pipe, 43mm carb and retarded Web 208.

55hp easy.


more pictures...

[370kingR]

Holy Sh@T Chad! Thats pretty serious. So the head is trashed then?

[chad502ex]

The absolute saddest part of this whole deal is that this was a Perfect work of DASA art shattered without even getting the chance to show its potential.

What kills me the most is that Dan from DASA extended the best customer service ever seen in any organization and I only wish that this head could have been the first to show its potential on a stroker. So; it's on to doing what others are questing for- Doing more with less. ;)


Sorry Dan- next 450 build I will demonstrate your perfection..

another pic.

[370kingR]

Man i feel terrible about that Chad. Thats just a horrible picture bro. Almost makes me sick to my stomach. Shake it off, there only parts.

[chad502ex]

yup, 10000 rpm can really cause alot of damage.

One of the first things I took off for disassembly was the carb, and when I looked into the carb I saw metal on the head side of the carb.

I knew it was going to be bad.

[Kilabanshee]

Holy he11 Chad! The picture almost brings me to tears.:(

[chad502ex]

Originally posted by 370kingR
Man i feel terrible about that Chad. Thats just a horrible picture bro. Almost makes me sick to my stomach. Shake it off, there only parts.

Thanks for your condolances Gary, but your right its only money, a lot of hard work and aggravation, many hours of of thinking only to get to the end of the inevitable.

Bottom line is that the biggest lesson I've learned is that my friends are sickened not only cause of the engine pop'n, but all the time I've lost this season not riding as much as I should have had I had the same hp on a stock reliable 450 bore.

[370kingR]

Originally posted by chad502ex
Thanks for your condolances Gary, but your right its only money, a lot of hard work and aggravation, many hours of of thinking only to get to the end of the inevitable.

Bottom line is that the biggest lesson I've learned is that my friends are sickened not only cause of the engine pop'n, but all the time I've lost this season not riding as much as I should have had I had the same hp on a stock reliable 450 bore.

Your preechin to the quir (sp) That has been the story of my life. You know how many times through the years i would sit and watch all my friends ride all weekend long on ther 300 ex's while i wondered why my mega horsepower bike blew up? Better to get there slow than not get there at all. I would end up drinking alot of booze those weekends :ermm:

Its a sickness

[chad502ex]

Originally posted by 370kingR
Your preechin to the quir (sp) That has been the story of my life. You know how many times through the years i would sit and watch all my friends ride all weekend long on ther 300 ex's while i wondered why my mega horsepower bike blew up? Better to get there slow than not get there at all. I would end up drinking alot of booze those weekends :ermm:

Its a sickness

truely is a sickness... I think I missed 3 or 4 rides with my group this year.

I'll tell ya, the only stroker i've own that's been bullet was the 502ex. That think still is a monster. Speaking of, I was thinking that in January when I get the new 450r build done, I'd re-degree the 502 for a dyno day of different results. :D

The ol' 502 dinasour still roars. hehe.

[chad502ex]

here's the side skirts of the 101mm

notice the bottom edge of the skirt how rounded or chamfered (sp?) it is. Also, the corners of the bottom of the skirt is almost folded inward toward the wrist pin (next pic.)

[chad502ex]

here's a shot of the piston skirt side load wear in the bottom corner of the skirt.

This is where if you look back at the cylinder picture the skirt of the piston pushed through into the cylinder.

a piston skirt to cylinder crack match.

[Dave400ex]

WOW. That is nuts. I think stock bore is the way to go. I know I've read that Baldwin is getting a good 55 hp with his engines, so I'm sure DASA could get you that or more...

[Pappy]

i am having my kids scour the area behind the dyno for pieces:eek: they will be placed on ebay:devil:


sucks bro...but you dont get anywhere without living on the edge. your free to build my engine any day of the week:macho

[brif]

Wow, those pics are ugly. With all the power the stockbores are making, it sometimes feels like a waste when you consider what some of these parts cost. I keep having in the back of my mind "when is mine gonna go" . I run a 99mm in a stock cylinder. I may go with that DASA kit for peace of mind. Atleast thats what I keep telling myself.

[chad502ex]

Originally posted by Pappy
i am having my kids scour the area behind the dyno for pieces:eek: they will be placed on ebay:devil:


sucks bro...but you dont get anywhere without living on the edge. your free to build my engine any day of the week:macho

Thanks Pappy. If given any chance, I'd be honor'd.

[Pappy]

yeah, now they are making good power with a stock bore, but they werent when the quads hit the dirt. it amazes me how now they can achieve more then what was even thought of just a short 18 months ago!

the baldwin 14-1 and a dasa head, RE pipe......

chad, clear your workbench:devil:

[86atc250r]

Bum deal on your engine Chad ---- however, from seeing those pics, I don't think the cyl cracking is what happened first....

Good luck on your rebuild.

[chad502ex]

Originally posted by 86atc250r
Bum deal on your engine Chad ---- however, from seeing those pics, I don't think the cyl cracking is what happened first....

Good luck on your rebuild.

what's your thoughts Gabe?

[86atc250r]

I'm thinking exh valves kissed the piston first.

Note the condition of the stems, the beating the head & piston took before the engine stopped --- the valves can also jack the piston sideways when it reaches TDC due to not enough room for everything.

[chad502ex]

and I always take photos as proof to my memory of my p/v clearance and place the picture in my folder with dates and mods to keep track.

from the notes ~.060" on the intake and ~0.070 - 0.080" on ex.

[chad502ex]

Originally posted by 86atc250r
I'm thinking exh valves kissed the piston first.

Note the condition of the stems, the beating the head & piston took before the engine stopped --- the valves can also jack the piston sideways when it reaches TDC due to not enough room for everything.

yes, I knew you were going to suggest that being the failure; so I was a little pre-emptive with the clay picture.

I don't discount that in the least cause obviously the ex valve damage, but maybe after the ring causght an edge on the cyclinder cave-in caused the piston rock to be greater than what the clay-in clearances were.

i guess one of those questions I'll ask God when I die, which came first the chicken or the egg,.....or in this case ,...... ???

Guess it don't matter now either way. When clearances are minimal and cyclinder becomes worn, and piston wobble becomes great, and cylinder cracks occur, its hard to predict what piston wobble would be like with all the ring friction scrapping the walls.

[86atc250r]

Piston to valve clearance doesn't guarantee against valve float -- remember, the engine died at 10,000 RPM.

I once lost a 400ex engine I bought that had been clayed also (not by me though) --- broken exh vavle at probably 10 or 11K RPM during a launch - luckily damage was minimal as the valve got in the center of the chamber and stuck in the piston.

Also remember that a cracked cylinder won't bend and break valves. It will just shut the engine down or make it run very poorly.

[kazpr]

Chad that SUCKS I know you lost alot of time and money now :( I however am excited to see what you can do with a stock bore setup! Good luck!!

[chad502ex]

Originally posted by 86atc250r
Piston to valve clearance doesn't guarantee against valve float -- remember, the engine died at 10,000 RPM.

I once lost a 400ex engine I bought that had been clayed also (not by me though) --- broken exh vavle at probably 10 or 11K RPM during a launch - luckily damage was minimal as the valve got in the center of the chamber and stuck in the piston.

Also remember that a cracked cylinder won't bend and break valves. It will just shut the engine down or make it run very poorly.

Ahhhh, great point Gabe!! I hadn't thought of float yet. Maybe, the Web springs seat pressure had gotten soft over the months,...

Your right! That would explain why I lost the exhaust shims on the top side if the springs got soft and the valve floated the shim would have had the chance to fall out.

Thanks Gabeborg, great insight.

A question God no longer needs to be asked!! :D

[chad502ex]

Originally posted by kazpr
Chad that SUCKS I know you lost alot of time and money now :( I however am excited to see what you can do with a stock bore setup! Good luck!!

Thanks Kaspr. Like always, I try to be forthcoming as possible with the information- even when its unfortunate for me.

[86atc250r]

Very steep ramp rates on that 208 cam, too....

[chad502ex]

Originally posted by 86atc250r
Very steep ramp rates on that 208 cam, too....

yes- steep they are. could have made the follower loft off the lobe at 10000 with not enough spring tension.

I'd buy that, but why the cylinder cracks in four locations where the skirt load is?

[86atc250r]

Piston jacked sideways by extra goodies floating around & taking up space

[BOONE450R]

Damn Chad, that really suxs.... :(

[chad502ex]

Originally posted by 86atc250r
Piston jacked sideways by extra goodies floating around & taking up space

metal bits yes, but vertical stress cracks in four symetical positions within the cylinder at p-c clearances less than .010.

i dont agree with that thoery with cylinder cracks.

I'm thinking after the first pull, before the valve failure, the cracks were already there and that would explain my difficulty in starting and my huge jetting change from 195 to 170 with the same a/f (12) dyno reading... Are you following what I'm suggesting here?

[chad502ex]

Originally posted by BOONE450R
Damn Chad, that really suxs.... :(

Yes Boone- **** happens.

[86atc250r]

Possible, I guess --- but don't you think it's odd that they're at the top of the stroke? Right where the piston would have been jacked by the valves?

Those two big holes are from impact - from the skirts - from something profound happening to the piston. The other cracks are hard to say -- lots of things going on with valves floating around in the bore where they shouldn't be.

Anything's possible -- Just looking at the most likely and logical chain of events.

I'm thinking that piston is still quite a bit lighter than a stocker -- I'm thinking that the nMotion jug is also stronger than a stocker - seems very unlikely to me it would simply crack on it's own - especially in such spectacular fashion.

It also seems like that dyno's wideband sensor has exhibited problems discerning wild jetting swings in the past too - may explain your AFR troubles that day. Leaded fuels will poison the sensor quickly.

[WhiteZee]

Originally posted by Kilabanshee
Holy he11 Chad! The picture almost brings me to tears.:(
yeah me too....iv been giggling like a little girl looking at these pictures.

[chad502ex]

Originally posted by 86atc250r
Possible, I guess --- but don't you think it's odd that they're at the top of the stroke? Right where the piston would have been jacked by the valves?

Those two big holes are from impact - from the skirts - from something profound happening to the piston. The other cracks are hard to say -- lots of things going on with valves floating around in the bore where they shouldn't be.

Anything's possible -- Just looking at the most likely and logical chain of events.

I'm thinking that piston is still quite a bit lighter than a stocker -- I'm thinking that the nMotion jug is also stronger than a stocker - seems very unlikely to me it would simply crack on it's own - especially in such spectacular fashion.

It also seems like that dyno's wideband sensor has exhibited problems discerning wild jetting swings in the past too - may explain your AFR troubles that day. Leaded fuels will poison the sensor quickly.

Those two big holes are on the clutch side of the cylinder. In other words, one cylinder hole (or cave-in) on the intake, and the other on the exhaust; so, if the ex valve were forced over to snap from the stems into the cylinder- then I would think that I would see the big cylinder hole impact on the exhaust side of the cylinder only. On the flywheel side of the cylinder are the two smaller cracks (second picture posted of the cylinder). hmmm...

As far as NMotion jug being stronger than stock, i believe it was when the cylinder was 99mm bore, but NMotion has had a bit of 101mm failures on thier strokers. I should have kept it 530. :(

Mobile Dyno's sensor was brand-new and fresh for the day. I saw him install the new pump head that day for Brian and my testing.

[BOONE450R]

Originally posted by WhiteZee
yeah me too....iv been giggling like a little girl looking at these pictures.

I see nothing funny about this!!:ermm:

Everyone knows that Chad and I don't see eye-to-eye on a lot of things, but to take shots at him in a time like this is just plain wrong.

How would you like to have lost SEVERAL thousands of dollars and countless hours of R&D??

[kazpr]

See chad even some of the .org people really do care and is not a big pissing contest. Sucks when a fellow Atv'r is in the DUMPS :(

[chad502ex]

Originally posted by BOONE450R
I see nothing funny about this!!:ermm:

Everyone knows that Chad and I don't see eye-to-eye on a lot of things, but to take shots at him in a time like this is just plan wrong.

How would you like to have lost SEVERAL thousands of dollars and countless hours of R&D??

Boone- Thanks. I expected heat from ppl as I certainly deserve it.

Your comments here, and Bad Habit comments over org. has exemplified "good ppl". As far as I'm concerned, those are the type of qualities I like and from here on out I plan on erasing any hostility and bad blood between us. Not asking you too feel the same, but for what it's worth. Good ppl you both seem behind the heated moments.

[WhiteZee]

Originally posted by BOONE450R
I see nothing funny about this!!:ermm:

Everyone knows that Chad and I don't see eye-to-eye on a lot of things, but to take shots at him in a time like this is just plan wrong.

How would you like to have lost SEVERAL thousands of dollars and countless hours of R&D??
the way he acts 99% of the time is what is just plain wrong.

[chad502ex]

Originally posted by kazpr
See chad even some of the .org people really do care and is not a big pissing contest. Sucks when a fellow Atv'r is in the DUMPS :(

lol kasp. It really isn't like that for me. I stll love it, even if my 550 is done, I still have a backup 502 to ride if I want to.

For some reason climbing on the 502 compared to the R just doesn't compare for me.

I'll just rebuild a new stock bore beast and be up and running on the dyno again to test the 60hp in January. Then, after the first dyno test, I'll try to leave it alone and just ride like i love to do...

[Pappy]

Originally posted by WhiteZee
yeah me too....iv been giggling like a little girl looking at these pictures.

poor taste if you ask me. what goes on elsewhere can stay there. i havent seen chad bash anyone in this thread so its uncalled for.

i dont buy into site versus site BS so button your sausage holder.

[Mobile Dyno]

:eek2: :eek:

[chad502ex]

the end.

[WhiteZee]

Originally posted by Pappy
poor taste if you ask me. what goes on elsewhere can stay there. i havent seen chad bash anyone in this thread so its uncalled for.

i dont buy into site versus site BS so button your sausage holder.
nothing at all to do with site vs site.

[kgbg]

i dont buy into site versus site BS so button your sausage holder.
That deserves a reset.

Not taking any sides, just thought it was a funny term.
Chad, that sucks. I wish I could not relate.

[400exrider0004]

Whats gonna be your next build chad????

[the_one]

Ahhhh, great point Gabe!! I hadn't thought of float yet. Maybe, the Web springs seat pressure had gotten soft over the months,...
"


How long has the 2nd head been in the motor? Risking that kind on motor on old springs dose not sound like a wise idea.

[chad502ex]

Originally posted by the_one
Ahhhh, great point Gabe!! I hadn't thought of float yet. Maybe, the Web springs seat pressure had gotten soft over the months,...
"


How long has the 2nd head been in the motor? Risking that kind on motor on old springs dose not sound like a wise idea.

Your right, not wise. I agree that I should have replaced the springs that I use to run on the 530 when I had the opportunity to change on the new DASA head and new Web 208 cam setup.

Before I ran the Mega X2 with more max lift. I never considering a cam with smaller base, steeper ramp being harder to control the loft over lobe from a cam with more max lift. Hard lesson I've learned to never use old springs when given the chance to replace and save a build. Trying to save the all-might dollar and not invest in new springs most likely cost me the build.

[chad502ex]

tonight i'll pop the cylinder holes open completely and picture the NMotion cylinder to water jacket thinkness and measure the walls with a micrometer.

These cracks are too symetical in the bore and align with the skirt side loading perfectly. Let's just see how thick the cylinder is at failure points. Tonight I'll cut the cylinder to see.

And for the record, I was not running nitro-methane as suggested by mixxer.

I'll also photo the cam and cam tower for ppl who wanted to see that.

I am interested in hearing all the theories though.

[Hammer trx450r]

Wow that is some damage. sorry to hear it chad. Good luck getting her back together

[chad502ex]

here's the NMotion cylinder wall thickness.

[chad502ex]

cam

[370kingR]

Wonder if the cam sprocket hub spun a bit upon valve impact? Are the lobes fine?

[chad502ex]

Originally posted by 370kingR
Wonder if the cam sprocket hub spun a bit upon valve impact? Are the lobes fine?

no cam sprocket spun at all the bolts wer a biatch to remove.

lobes look fine

[TWISTED]

I think I'm gonna puke!!!! Sorry about your loss.

[chad502ex]

Originally posted by TWISTED
I think I'm gonna puke!!!! Sorry about your loss.

twisted- you crack me up. I had a feeling you'd respond :)

Don't worry next time we meet again you'll see something just as strong. ;)

[the_one]

4.88mm should be thick enough? If I read correctly. What was the final comp ratio on the motor? Was it a long of short rod stroker? The NMotion jug shouldn't be much differnt then what Falicon offers. Just thinking of side load? They said those kit were holding up well. But I only talked to a salesman. What were the p-c clearances at the base? Seeing the wear, wear can happen quite fast if there was a oiling problem.

Just to many things to consider, tough luck.

Also +10000 rpm might have been a bit much for a stroker. Also that uni-cam has me wondering sometimes. It's always seem the exhaust valves are the ones to go pop.

[chad502ex]

Originally posted by the_one
4.88mm should be thick enough? If I read correctly. What was the final comp ratio on the motor? Was it a long of short rod stroker? The NMotion jug shouldn't be much differnt then what Falicon offers. Just thinking of side load? They said those kit were holding up well. But I only talked to a salesman. What were the p-c clearances at the base? Seeing the wear, wear can happen quite fast if there was a oiling problem.

Just to many things to consider, tough luck.

Also +10000 rpm might have been a bit much for a stroker. Also that uni-cam has me wondering sometimes. It's always seem the exhaust valves are the ones to go pop.

i would think ~5mm would be thick enough too on 101mm dez

The compression ratio was 13:1 with ~6cc removed on 0.040" decked head and about 11.5:1 dynamic. piston deck height was ~0.030" and 0.027" on head gasket; -12 degrees of cam timing with perfect balance of p-v clearance on each side; rod length 4.384" falicon knife rod; +4mm stroke harmonically balanced crank.

As far as the ex valves usually the ones going pop, there's always a lot of consideration for p-v clearance being >0.06" due to piston wobble, but tell me who has measured the valve wobble at 10000 rpm? There has been high speed filming cameras installed in single cyclinder engine at these rpm's to study the effects of valve wobble. These cameras film an increase in wobble on the exhaust side due to their cylinder entry angle, and wobble relative to rpm. The wobbling exhaust valves toilet bowl on the seat too. Many think bounce, but bowl. Intake valve angle in the 450r has little or no wobble. Ever thought why the crf has two different valve diameter sizes? I think I do now. Anyway, there is no way to guestimate the amount of wobble on the ex side, so I ignored it, maybe it was eventually to much piston and ex valve wobble that finally after the heat soak and final cylinder expansion caused contact

NMotion jug I bought for the stroker was in raw form- 2mm taller than the 520 kits.

it would probally be easier if I supplied blueprints; just kidding man.

guess it doesn't matter much cause I'm done working all those clearance issues with reduced cam tower bosses, sunken guides, lightened followers, lightened ultr-light pistons, hardened rods, extra cooling, higher octane, lightened flywheels, custom ignition curves, maintenance issues, reliablility issues.

I want to gas and go, and my next project will get back all that was lost in the stroker without the loss in hp. See ya over 55 ;)

[370kingR]

Good lord :eek2:

Anyone who cant appreciate what went into that motor is plain just being ignorant.

That was alot of thought and skill in my opinion and 85 percent of the atv world couldnt come up with all that and make it work so i tip my cap to you Chad. Im not kissin butt or just typing to hear myself think, i truely am impressed. Lessons get learned and you move foward. Thats life.

[4ABURN]

First of all chad sorry for your loss. But just a thought you might want to talk to some crf owners because they rev to 11500 so they are at 10000 all the time maybe they can anwser your clearance questions.:ermm: :(

Anyway best of luck on the next one, I know it will rock!!!!! :D

[chad502ex]

Originally posted by 4ABURN
First of all chad sorry for your loss. But just a thought you might want to talk to some crf owners because they rev to 11500 so they are at 10000 all the time maybe they can anwser your clearance questions.:ermm: :(

Anyway best of luck on the next one, I know it will rock!!!!! :D

Thanks 370kingR and 4ABURN!

I figure ~$1700.00 more to rebuild to stock config with new DASA head. Just going to have to wait till after the Holidays. Com'on January!!!!

[BSTURDIVANT]

We've seen a lot of nascar style engines with similar failures.
Damage started when valves broke! At 10,000 rpm, the pressure exerted on the piston from side loading(valve head on top of piston opposite of the cylinder breakage) broke the cylinder.

Question is? what caused the valves to break?
1- bad valves - some crf 450 stainless valve replacements have been failing.
2- valve to piston contact
a- improper clearance
b -valve float
c- cam to crank alignment change

After looking at the pictures of the clay check, the verticle clearance looks good if checked after final degreeing. The clay thickness on the intake OD looks a little thin, but hard to tell without measuring.
Some valve spring kits use the same springs for intake and exhaust and won't keep the exhaust valves closed at high rpms.
Check your springs first- if the same springs- definately floating at 9000 rpms because of the heavy rocker!
Sounds like the exh. valves were hitting and starting to leak giving you mixture problems.

Just a few things to ponder before you give up on that monster!
Good build with good results, just a shame that a valve or spring failure riuned it!

[370kingR]

If Woody had gone straight to the police, none of this would have happened









Sorry, i dont know what got into me :ermm:

[honda350r]

Chad,here is a picture of a stock 450r cylinder after a rod let go.. It broke very simular except for alot worse.. The head had no damage...

[chad502ex]

Originally posted by BSTURDIVANT
We've seen a lot of nascar style engines with similar failures.
Damage started when valves broke! At 10,000 rpm, the pressure exerted on the piston from side loading(valve head on top of piston opposite of the cylinder breakage) broke the cylinder.

Question is? what caused the valves to break?
1- bad valves - some crf 450 stainless valve replacements have been failing.
2- valve to piston contact
a- improper clearance
b -valve float
c- cam to crank alignment change

After looking at the pictures of the clay check, the verticle clearance looks good if checked after final degreeing. The clay thickness on the intake OD looks a little thin, but hard to tell without measuring.
Some valve spring kits use the same springs for intake and exhaust and won't keep the exhaust valves closed at high rpms.
Check your springs first- if the same springs- definately floating at 9000 rpms because of the heavy rocker!
Sounds like the exh. valves were hitting and starting to leak giving you mixture problems.

Just a few things to ponder before you give up on that monster!
Good build with good results, just a shame that a valve or spring failure riuned it!

BSTURDIVANT,

yea, and I was just getting started with that monster too! dang. If it hadn't broke loose like that it would have been more. dang.

When pictured after diassembly, the postion of the valve heads atop the piston was after the engine spun down on dyno braking and after my kicking the kicker to feel the bootom end resistance in my leg (none). Imediately, I thought cam chain popped, until I removed the valve cover at home. Another worthy note on the symetrical cylinder cracks, each of the four started at the base of the water jackets.

I'd hate to rehash on tiolet bowl effect, but the more I think about it the more I question the effect. As the valve is violently pushed inward, the head of the valve spirals like tiolet water in a bowl, almost tornado like until its violently pulled back toward the seat. Because the valve head is still spiral like when it strikes the seat, it bounces like a penny on a glass table. Now, do this thousands of times per minute and get an understanding of how those valve heads move about. Stress test for sure.

I'm still leaning on answer #1 you indicated about faulty valves.

This build was IMO just right. In some of my previously builds, I knew when something wasn't quite right; but this one went together as I wanted with all details checked. Maybe I should have just kept the 550 I was running (NMotion head), and not try the new DASA head and new cam.

Oh wanted to mention that the EX springs are double rate with more spring seat pressure than the double rate spings on the Intake. Come to think of it again, these springs were fine on the NMotion head minutes of run time before this incident.

[chad502ex]

Originally posted by honda350r
Chad,here is a picture of a stock 450r cylinder after a rod let go.. It broke very simular except for alot worse.. The head had no damage...

WOW hond350r thanks for posting!!! :eek2:

Interesting enough, those cylinder cracks do look almost the same as mine; plus, they appear to be located on the clutch side of the engine too!! huh!! one on the intake side and the other on the exhaust side, not both cylinder cracks on the exhaust side of the cylinder,... symetrical too- along the piston skirts due to side loading. wonder if the rod angle in the 04/05 is too severe compared to the rod angle in the crf...

I'm still on the ex valve wobble warpath. Anyone got more info on valve wobble with valve heads snapping off as a result of?



let's call HONDA and claim they owe us a refund! Think HONDA searches these board for extremely stress reports? LOL!!

[honda350r]

here is a picture of the whole cylinder

[chad502ex]

Originally posted by honda350r
here is a picture of the whole cylinder

ya know, see'n your picture that angle reminded me when John at NMotion was describing that the NMotion jug had to beefed along the base too for the cylinder bolts to reduce cylinder flex. wonder if the jugs are twisting a bit too much?

look at my picture of the NMotion jug flipped upside up. This is the same side as the side where my huge cylinder cracks wer and also the same side as honda350r's huge cracks were. You can even see where the water jacket ends on the outside where the vertical cooling fins begin toward the top side of the cylinder.

Check out the NMotion cylinder bolt hole enlargement. I wonder if that was needed as re-enforcement? hmmm./

[400exrider707]

Originally posted by honda350r
Chad,here is a picture of a stock 450r cylinder after a rod let go.. It broke very simular except for alot worse.. The head had no damage...

Holy cow that thing still has the cross-hatch in it, couldn't have been too old when it let go!

seeing these pictures makes me think about when girls watch sad movies and are sobbing through the whole thing.......well this is the guy version, looking at all these pictures of horrible engine failure with all of these high $ parts makes me wanna cry!:ermm:

[slamdak8782]

Definitly the valve dropping was the first problem. The brittleness of the aluminun cylinder imo couldnt have helped things. And last thing. I think your on to some thing with the rod angle theory.

[SLIDING]

Dyno blow ups.

We can all guess as to why it failed and let go. An educated guess is all it will be!

Im with the floating of the valves. I think you floated the valves on previous runs. This allowed piston to valve contact (Slightly bent exhaust valves). Which caused your O2 sensor readings to go out the window. This is also why it was hard to start.

The next thing to try would be more valve spring seat pressure as well as a reduction in valve train mass.

I remember a well known F1 driver being asked by one of the engine techs about the engine blow up he had just experianced.

Quote
Did it sound any differant than the last one! No it just went bang and stopped!

With millions of $ spent there still guessing as well. So how are you meant to know.

Build the next one more mild. Then you can enjoy more riding time with less stress.

Remember riding the thing is more fun than watching!

Save your dollars for the after ride beers.

Ride on!

Good on you for trying your best to make big HP.

:)

[slamdak8782]

I think the thing to do next time is only take it to 9500 RPM. Should be a lot safer that way. As much as people hate it physics still come in to play. And at least that way you live to ride another day. Personally I wont ever be running an aluminun jug on my quad unless I dont have choice. But Im glad chad has the balls to step up and try the things most of us never do. For most of us a cam or pipe would be good enough. Also chad on the comparison dyno chart what was the build of the 250r? And what was done to the 440ex like cam port work and so on. It would have been cool to see a chart with a [piped 450r on there. Funny how you almost never see that comparison. Probably not as far as what most would think. That was a nice curve on the 440 but I think my 440 would have represented better.

[Mobile Dyno]

I'll take that challange...lol

[FHKracingZ]

Theres no doubt about it that valve float or valve stem keepers failed and let the exhaust valves drop. Theres nothing else logical that could happen going by your pictures.

[chad502ex]

Originally posted by FHKracingZ
Theres no doubt about it that valve float or valve stem keepers failed and let the exhaust valves drop. Theres nothing else logical that could happen going by your pictures.

keepers were in place.

[chad502ex]

Originally posted by slamdak8782
I think the thing to do next time is only take it to 9500 RPM. Should be a lot safer that way. As much as people hate it physics still come in to play. And at least that way you live to ride another day. Personally I wont ever be running an aluminun jug on my quad unless I dont have choice. But Im glad chad has the balls to step up and try the things most of us never do. For most of us a cam or pipe would be good enough. Also chad on the comparison dyno chart what was the build of the 250r? And what was done to the 440ex like cam port work and so on. It would have been cool to see a chart with a [piped 450r on there. Funny how you almost never see that comparison. Probably not as far as what most would think. That was a nice curve on the 440 but I think my 440 would have represented better.

I'm not sure the build on the 250r. I was working mobile dynos computer trying to get a sense of the area under the curve between the different machines.

Mobile,

what challenge?

[Mobile Dyno]

I was just joking around with slamdak8782 about him saying his 440 would put down better #'s. Just joking around saying I would challange hime to a race. Thats all

[chad502ex]

Originally posted by Mobile Dyno
I was just joking around with slamdak8782 about him saying his 440 would put down better #'s. Just joking around saying I would challange hime to a race. Thats all

That would be kewl to watch!!

When you building a stroker?

[Mobile Dyno]

When I get the money:rolleyes: ...I would like to do it this winter

[chad502ex]

Originally posted by Mobile Dyno
When I get the money:rolleyes: ...I would like to do it this winter

we know your rich with all the dyno time ppl are renting out from you,...

[slamdak8782]

Well I would really like to know what my 440 puts out anyways and I wouldnt be scared to race ya if you had a 440 like mine. Anyways win some lose some but Id have a blast win or lose.

[slamdak8782]

well my 250r is pretty close to stock but I think it would take my 440. I will definitly accept the challenge on my R :D ;)

[slickta]

We had an engine blow up earlier this year. The engine had a 13:1 piston and a hot cam. The failure looked similar to yours. Metal in the carb, valves were broke off and shoved back in the ports and the cylinder was cracked. I beleive the valves floated and bent and hit the piston. When the valves broke the piston then loaded the cylinder and cracked it. We were racing on a 3/8 mile track. We had the same type of failure with a 440ex. Same type of failure and looked the same. The only difference was the cylinder was able to be replated. Both times were due to valve springs. I guess you live and learn. The 450 had stock valve springs but very low run time on engine. The bike was always raced and sustained high rpms on big tracks. Should have used a/m valve springs the first time.

[punker69q]

Originally posted by chad502ex
i would think ~5mm would be thick enough too on 101mm dez

The compression ratio was 13:1 with ~6cc removed on 0.040" decked head and about 11.5:1 dynamic. piston deck height was ~0.030" and 0.027" on head gasket; -12 degrees of cam timing with perfect balance of p-v clearance on each side; rod length 4.384" falicon knife rod; +4mm stroke harmonically balanced crank.

As far as the ex valves usually the ones going pop, there's always a lot of consideration for p-v clearance being >0.06" due to piston wobble, but tell me who has measured the valve wobble at 10000 rpm? There has been high speed filming cameras installed in single cyclinder engine at these rpm's to study the effects of valve wobble. These cameras film an increase in wobble on the exhaust side due to their cylinder entry angle, and wobble relative to rpm. The wobbling exhaust valves toilet bowl on the seat too. Many think bounce, but bowl. Intake valve angle in the 450r has little or no wobble. Ever thought why the crf has two different valve diameter sizes? I think I do now. Anyway, there is no way to guestimate the amount of wobble on the ex side, so I ignored it, maybe it was eventually to much piston and ex valve wobble that finally after the heat soak and final cylinder expansion caused contact

NMotion jug I bought for the stroker was in raw form- 2mm taller than the 520 kits.

it would probally be easier if I supplied blueprints; just kidding man.

guess it doesn't matter much cause I'm done working all those clearance issues with reduced cam tower bosses, sunken guides, lightened followers, lightened ultr-light pistons, hardened rods, extra cooling, higher octane, lightened flywheels, custom ignition curves, maintenance issues, reliablility issues.

I want to gas and go, and my next project will get back all that was lost in the stroker without the loss in hp. See ya over 55 ;)

Sorry to bring on a old thread, but I was thinking about your failure and I made some calculus. At 4,88 mm thickness, the cylinder walls are way too thin. With the kind of presure a cylinder wall will see, the stress in the walls will reach over 20 000 psi, which is way too high for reliable operation with any grade of aluminum. Also, a four point seizure is also a sign of too small piston to cylinder clearance.

What kind of clearance where you running? Maybe it was too small, after all, a 101 mm forged piston (over 4''!!) needs more clearance than a smaller piston.