416ex Rod SNAP!!!?? something went CLANK CLANK

[400exredrider]

hey guys,,, just got the 416 done and 3rd ride and i adjusted the WB e series,, added plates,,, take it out pull a quick wheelie,, and boggs,, thenk clank clank clank clank until i stop,,, i was thinking cam chain but i opend up the valve adjust bolts and the cam sprocket and chain were still there,, i dunno if it could have been a valve get smacked or if it was the rod bearing or the rod it self but im leanin towards rod...:( about how much is a hardend rod and would you think the piston is messed up?? its hard for me to tell.. i assembled it all and ive done it before so no big deal but this thing put out tremendous power until so i know something gave on her,, let me know any guesses you guys may have on it and like i said, im not tearin back into it ill leave that to someone else for this,, anyone ever had a rod snap on a 416!? the setup is below.. tell me what you think

[cals400ex]

the piston will probably be damaged if i had to guess. a good rod like a sparks or carillo should be a little over $200. take it apart and see what you find. i have seen some rods fail on similar bikes. i think it is a luck of the draw thing.

[400exredrider]

im just hopin its not tho,,, it kinda sounded like it mighta been a crank bearing but ill take a look and let you guys know,,

[400exredrider]

btw i wasnt goin but 20mph when it happend:confused:

[dork]

does it still turn over?

[TCracin440ex]

i dont think it was your rod because if it was your rod it woulda busted the case open...even at idol it woulda busted the case...i had a rod snap on my old honda recon and all it was doing was idoling...and busted clean thru the case

i think your valves fell dude...that happened to my old 92 250x i was ridding thru the woods and i heard clunk and the bike just stalled...took the topend appart and the valves had fell and embeded themselves in the piston....check your valves i honestly dont believe its the rod

[2muchquad]

its really hard to speculate until you tear it down.i doubt its your main bearings though.could be a bottom end problem or maybe your clutch basket came off!wont know til' you tear it apart,i hope its nothing to serious,we all have been there before..:(

[400exredrider]

thats the first bit of enlightning news ive heard about it..i dont thing it was the rod either, i have seen somepics of a rod blow and its not good,, mine has no damage to the case... and i havent tried to turn it over because i dont want to mess anything up, if its the valves ill be pretty happy because thats a minor fix,, unless it killed the piston.. which i wasnt goin fast so maybe it will be ok.. ima tear it down soon today and take a look i think it could be the valves..

[TC426EX]

Dude, it was most likely not your rod. I know from experience!!! I just blew a rod in my 426 and I can stick a fist through the hole it blew in my cases and bottom end. No easy way about it dude, youre just gonna have to get yourself a clymers manual, and get down and dirty in there tearing it apart. If you are running high compression, even only like 11:1 I would reccomend you put a HD rod in there NOW. Its better to spend the 200 (well plus 100 to get the crank work done) now instead of making the same mistake as me. Now I have had to buy a complete new bottom end for my bike, cylinder, cylinder bore, piston kit, rod, and everything pushing me well over 700 bucks. Laz at GT Thunder, who is gonna install my HD rod, said that under stress, the 400ex crank has a tendency to come out of true. Therefore, most reputable engine builders who do crank work will also true and weld it up. While you got it apart, I would check any and all bearings, especially in the crank, which you think may need replacement, and do it now. Like I said, even if it wasnt your rod, replace it... I was told the stock rod was barely good enough for a "wed whacker"...

[duke416ex]

I know you said the cam and chain were both there, but maybe it jumped time and the valves were hitting the piston. If you weren't wide open it might would have still run for a little bit, atleast until it bent the valves to bad to run. When you looked at the cam was the rockers really loose? If they are really loose on tdc, take the head off and I bet they are bent to where they can't seal off and are hitting the piston.

[400exredrider]

tc426, the motor ws fresh,, ive dug into it before so its no big deal today when i get time i will tear into it,, thats kinda what i was wonderingabout if it skipped a bit and knocked the valve,, im prett sure it hit enough times to bend them severly or break them at 20mph it clanked quite a few times before dieing, as where a rod im thinkin that it would stop it immediatly,, i will figure it out tonight when i tear into the top end,,, hopefully i can just leave the cylinder on because it would be good news to me if it were the valves because that is a cheap fix as for the rod,, ill look it over if i have to but i really havent heard of many 416s blowin a rod so i guess this will be interesting to find out... ill keep you all updated

[duke416ex]

Is the motor turning over when you hit the start button, or what does it do? Any bets on what it is, I bet jumped time, anyone else. Come on let's get a little excitment going before he tears it down!:macho :devil: :D

[400exredrider]

it turns yeah but seems like there isnt much compression and you can hear metal clankin,, well find out tonight as soon as i get her torn down!

[400exredrider]

426..how much did your titanium valve/spring setup cost ya

[TCracin440ex]

im stickin to the valves deal...

[BIGRED400]

Just a thought , Is it possible your Cir clips were on good where the pin connects the piston to the rod ??? Not saying that is it ,just a thought. Was the de-compression spring took out on the new cam installation? BTW I have been running my 416 JE 11:1 w/PC-9 coating and Thermal barrier coating
http://www.swaintech.com/4whl.html
w/stock rod with no problems yet.

[400exredrider]

Well the results are in and it dont look good,, 426 you were correct,,, i dropped one exhaust valve for not much of an apparent reason,, it gouged into the piston and made a hole the head looks to be salvageable and so does the cylinder.. ill post pics in a min

[TCracin440ex]

i was right....i said valves first

[400exredrider]

oh i got you two mixed up anyhow here are some pics

[400exredrider]

.. this sucks i hope that head is salvageable

[duke416ex]

I said valves too, ooks kinda messy, pics are blurry, but did the oil come through the piston or head?

[400exredrider]

oil came thru the head

[TCracin440ex]

gonna need a new piston and proally a new head...i would PM mikeboone about a head thats ported and polished he will swap you for your stocker...idk if he will charge extra cuz your valves are bad...i wouldnt replace only 1 valve....replace all 4....but if your stock head is salvageable get all 4 valves....

might want to check your cylinder too make sure the valve aint scar the cylinder

[400exredrider]

i think its salvageable,,, it has a slight gouge in it where the valve hit but i think it can be ground smooth again

[400exredrider]

plus i dont wanna get ridda that because its already ported

[TCracin440ex]

i dont know about that dude....i had a gouge in my head and i was told by my mechanic to buy another 1 because it aint worth salvaging

[Plante400]

i run my 11:1 with a stock rod on my 440... ive had it for over a year and i dont have a whole in my case.. but maybe when i put a cam in i will put a hardend rod in.. hmm

[TCracin440ex]

i think the reason for the valve breaking is the same reason my valve on my 250x broke....you had your valves adjusted too tight and when the piston came up it hit the valve breaking it off....thats what i think

[400exredrider]

ill see what nicholas cycle says about it.. im guessin he can do somethin about it its not really bad at all

[Plante400]

yeah so i meant to put that in the other "rod" thread/ my bad

[400exredrider]

if i have to replace the head thats a head plus alot of cash for another port job

[TCracin440ex]

o0o...well trade that old head for another head thats already p&p...PM mikeboone and see what he says

[400exredrider]

i PMed him
but i dunno how much hed charge me for

[mikeboone]

The head looks like you may can save it. I dont think it will be as good as before but worth a shot. After stripping and beadblasting you/shop can tell more if some minor grinding can help out. The fuel/air mix will be disrupted with peaks and valleys in the dome so the fewer the better. If the head ends up needing 3 angle valve job your prolly better off money wise to get a new one.

[400exredrider]

mike would you beable to do this? i dont want anything to be messed up really so how much would it cost me to exchange you? if youd take this one

[mikeboone]

I dont have anything to exchange it for. The only 400 parts I have right now are set of center cases and a flywheel. I branched out into Yama's and such lately instead of focusing on just the 400's.

If you'd like I will check it for free (plus shipping) If it looks like the shop can smooth it up I will let you know either way.

Costs would be minimal labor wise; I will only charge what the shop does me. You will need at least new exh valves. Kibbllewhite's are about $40/each and work great. I will strip it, reassemble, and beadblast to look new for $50 including new seals and crush gaskets. I have sold nearly 100 P&P Heads so assure your head will be in good hands. I personally strip, blast, and reassemble each one.

[400exredrider]

if you think you can get the gouge outta it and get it back to normal ill prolly let you do that once i get 50 bucks in my account for paypal

[400exredrider]

plus the 40 each for kibblewhites

[Barney]

I did this a few years ago mine looked a lot worse than yours.
You well have to look at the valve seat in the head it looks that
the damage is very close to the valve seat in the head, But
that can be fixed also with welding an a new seat. Can you get
out the spark plug? This also can be a problem too. It can all be
fixed.

[400exredrider]

sparky plug came out,, the seat istn damaged really,, thank god, because the valve ended up lodged up in there

[400exredrider]

235 dollars in parts plus labor

[400exredrider]

scratch that,, took it to the mechanic and the head is beyond repair and has to be replaced 500dollars new!! :eek: that pisses me off new piston should i stay 416 or go 426? black diamond valves and springs and new port job along with another bore:o :( over 1 grand with labor

[TCracin440ex]

damn....did you ever find out the reason why the valve broke off...i believe it broke off because you had your valves adjusted too tight....check ebay for a stock head...they have 400ex motor parts all the time...

find an atv salvage yard see what they have...i know a guy on here name is quadcustoms he parts out alot of quads...might want to give him a shout see if he has a 400ex head...

[400exredrider]

it was just stressed,,, he thinks its because the cam over stressed it

[TCracin440ex]

i dont know where to tell you to find a good used head at a good price....yamahaoftroy.com sells brand new heads but they are 479.95 plus shippin they will stiff you on shippin too..

speakin of heads...i found my old 250x head with the valves broke off...ill clean it up and take a picture of it and post it...that head looked like crap..idk where the piston is but the piston looked worse than the head...the pistion had 2 valves embeded in it

[TCracin440ex]

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4540589147&category=43977&sspagename=WDVW


here you go....2 days left with no reserve...id keep an eye on it if i were you

[400exredrider]

that kinda looks like crap
i dont want this to happen again so i might just try a new one well see

[400exredrider]

should i do 426 or 416?

[TCracin440ex]

i dont know man its your money...gonna cost you extra to get it bored to the 426 tho

[400exredrider]

has to be re bored anyway,, the cylinder was scored.. i found a head on here thats ported for 285 shipped im lookin into that

[TCracin440ex]

o0o...since its gotta be bored do the damn thing...i wish i had the money to afford a 426ex piston, cam, and have my head ported and polished...thats what i want to do to my bike...i kno a good mechanic that will do it for me at a good price...and he builts strong motors but money aint workin in my favor right now...

[400exredrider]

yeah,, i dont really wanna spend cash on this but i have to now so,, its better spent on the 450r