CR500 in 400ex frame. Lets talk mounts...

[QuicktimeRacing]

Ok guys, here's the deal. I made one trip to the dunes and had some problems with vibrations causing cracks in my engine mounts at the frame. I really don't want the comments about how impossible this is and "give up why your ahead".

I'm looking for advice on mounting locations or some pics of mounting points for this setup. If it were a perfect world and I had more money I might just give up on this but it's not so I need to make this work for now until I can afford a different setup.

If anyone has some pics or words of wisdom on how to mount this motor to avoid further problems I would love to hear about them or even better see some pics.

The Vibration really doesn't bother me as a rider and when it's together the thing moves like a hell but obviously the frame cracking is a problem that I would like to fix. That being the case, here's hoping I get some good input. Thanks guys! ;)

[2muchquad]

I had a yz490 motor in my 250r frame earlier this year.The vibration wasnt really an issue even though i was told it would be,only when revving it up in neutral were the vibes noticeable.Im had the normal real mount throughth swingarm but then i used those big rubber spacers that come on those "load leveling" coil spring spacers with holes drilled in them for the front mounts.I miss that thing:(

[Black Sheep]

The problem is your trying to fix the unfixable. it's not about strength but harmonics.

square tube frames do not have good harmonics. therefore when you have a lot of vibrations you get cracks.

People have been trying this for years with poor results.

likewise people have been putting CR500 motors in ATC 250R frames for years with good results. But, the ATC has a round tube frame.

I do remember a guy who put a CR500 in a TRX 250R chassie with good results but i think he used some sort of rubber mounts for the motor.

[QuicktimeRacing]

A 400ex has a round tube frame...

[C41Xracer]

rubber mounts are the way to go for that, but some vibration will be there still

[2muchquad]

Surely,my 250r has a c/b and theres vibration,my 400ex has vibration to a point as well.Bottom line,if somebody wants to do something,they will.:)

[QuicktimeRacing]

Originally posted by 2muchquad
Surely,my 250r has a c/b and theres vibration,my 400ex has vibration to a point as well.Bottom line,if somebody wants to do something,they will.:)

A C/B?

[Black Sheep]

Originally posted by QuicktimeRacing
A 400ex has a round tube frame...

well now don't i feel stupid :huh i was thinking of the TRX 250R and 300ex frames.

[rustyATV]

Originally posted by QuicktimeRacing
A C/B?

Counterbalancer


See what you can get from the pictures in this auction before they're taken down.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=STRK%3AMEWAX%3AIT&viewitem=&item=280260906794

[00.400ex#55]

Solid mount is the only way to go, mines been together for over a year and its just fine. Also my welding skills are not exactly profesional and were done with an 80amp welder... ya, if i can do it others can. Check out these links and youl get some more info from others, most with vibration problems have there motors rubber mounted.

http://forums.everything2stroke.com/honda-trx-250r/19157-cr500-250r-frame-64.html

http://www.trx500r.org/forums/

heres a picture of mine
http://i203.photobucket.com/albums/aa289/quadracer56/P6020001.jpg

video i made to try and show vibration when it was running like ***.
http://i203.photobucket.com/albums/aa289/quadracer56/th_P1010014.jpg (http://s203.photobucket.com/albums/aa289/quadracer56/?action=view&current=P1010014.flv)

dyno chart with a fmf 250r pipe and bad crank seals
http://i203.photobucket.com/albums/aa289/quadracer56/P1010022.jpg

[2muchquad]

62 ft/lbs of torque! holy sh@t.that would be a blast to ride.that should pull 16/33 gearing... for woods lol:D

[atvmxr]

max 43hp?? yeah I'd say that motor was hurt just a lil bit.. :D

[QuicktimeRacing]

Originally posted by 00.400ex#55 [/i]
[B]Solid mount is the only way to go, mines been together for over a year and its just fine. Also my welding skills are not exactly profesional and were done with an 80amp welder... ya, if i can do it others can. Check out these links and youl get some more info from others, most with vibration problems have there motors rubber mounted.


Can I see some more detailed pics of your engine mounts and your exhaust mounts? I would greatly appreciate it. -Trent

[00.400ex#55]

ya heres a few

http://i203.photobucket.com/albums/aa289/quadracer56/P2250050.jpg

http://i203.photobucket.com/albums/aa289/quadracer56/P2250054.jpg

http://i203.photobucket.com/albums/aa289/quadracer56/P2250052.jpg

http://i203.photobucket.com/albums/aa289/quadracer56/P2250048.jpg

http://i203.photobucket.com/albums/aa289/quadracer56/P2250047.jpg

http://i203.photobucket.com/albums/aa289/quadracer56/P2250046.jpg

http://i203.photobucket.com/albums/aa289/quadracer56/P2250043.jpg

http://i203.photobucket.com/albums/aa289/quadracer56/mounts.jpg

Edit: no making fun of my welds :D

[ss440ex]

It looks like you thought it out.
I like the design,
and fitting looks good too!

[rustyATV]

Originally posted by 00.400ex#55
Edit: no making fun of my welds :D

I was just about to say that I felt better about mine:D


*Edit*

Have you thought about trying to fit a 250R airbox on there? Or is it not a concern?

[2muchquad]

looks good to me,its hard to mimic welds of a computer:)

[C41Xracer]

Originally posted by atvmxr
max 43hp?? yeah I'd say that motor was hurt just a lil bit.. :D



DID YOU EVER THINK ABOUT THE PIPE? IM WONDERING IF THE 250R PIPE WOULD LIMIT THIS MOTOR TO BRING OUT ITS TRUE POWER. WHAT ABOUT A BIG BORE PIPE?

[atvmxr]

dont go there... :D

I already made some comments about the pipe and silencer and was told he's happy with the way it is...

i believe he said for the dyno run the crank seals were bad, so It probably makes more power after he got it fixed...

:macho

[00.400ex#55]

My pockets are only so deep, the pipe came with the motor so I used it. Just beacuse it's "done" dosn't mean its staying that way, everyone knows it's never done. If funds allow im hoping to have Jaws performance build a one off pipe for me this winter and have them go threw everything and do some more dyno runs.

[C41Xracer]

i was just curious about the pipe, im doing the same build thats why im asking

[QuicktimeRacing]

I've done alot of research on this in the past couple days. I've decided solid mounting is obviously not the way to go as it has already failed me and unless you bullet proof everything I can't imagine how that would ever work. Not saying it can't be done but I am going to try another route. I am going to use Polyurethane bushings at 2 of the 3 mounts. The third being the swingarm pivot mounting location will stay original. I haven't decided how I am going to approach the pipe mounting just yet but at this time the silencer is rubber mounted. I will be sure to let you guys know how it comes out and throw some pics up in the next couple days. Thanks for all the input!

[2muchquad]

Just get at it man,trial and error thats all.Obviously your gonna get a lot of sorted opinions but if its something you want to do,go for it.It seems too many people go on what they"heard" instead of what they "have seen".When i had my cr250 motored blaster all i heard was "it'll vibrate,no c/b" etc etc.Well after almost 3 years all i ever did was have a head stay crack,no big deal.go for it:)

[00.400ex#55]

If I may make a sugestion, read the entire thread on everything2stroke in the previous link I posted if you have not already. It may take a while but there is a ton of information on there as well as a lot of pics. Think everything threw before you do it. I drew all my plans out and didn't start untill I was happy with my design.

For the pipe i used rubber. That is a must! I did crack my pipe 3 times eventualy ripping a large hole right out of it when I had it solid. If you can't make out my pictures well enough to see how mine is mounted I can take more pics if you want.

If you have any pics of yours im sure we would all love to see.

[Jonny B]

Hey guys...that was me selling the Laeger's TRX500R that you posted earlier and I just wanted to say that thing was a beast!!! That frame was designed for a cr500 and the engine was rubber mounted...vibrations should be expected but that had very little at idle and none under a load. Cr 500 engine quads should be ridden hard like any 2 stroke and spend little time idling around. I think the guy who wanted to use poly-bushings has a good idea and good luck with the project.

[rustyATV]

Originally posted by Jonny B
Hey guys...that was me selling the Laeger's TRX500R that you posted earlier and I just wanted to say that thing was a beast!!! That frame was designed for a cr500 and the engine was rubber mounted...vibrations should be expected but that had very little at idle and none under a load. Cr 500 engine quads should be ridden hard like any 2 stroke and spend little time idling around. I think the guy who wanted to use poly-bushings has a good idea and good luck with the project.

If I didn't already have a project quad, I would have jumped on that when I first found it. Any chance you sold it to a guy in Georgia?

[Jonny B]

No...that frame, swinger,etc. went to a lucky guy in Cali...I regret letting it go because I will probibly never get a chance to own another one of those very rare laeger's chassis's...only seen three in my life...one in a mag...mine...and one a guy sent pics to me of his when he saw my add. I still can't believe I let it go but bill's needed to get paid...If you want to see some pics of the mounts let me know. (very profesional) The rear motor mount went throught the swinger pivot bolt which might be tough on a 400ex and people have told me that to do the conversion on a 250r frame, you would need to cut the lower frame tube that the pegs are mounted to which weakens the frame. I also would try to modify the head stay to accept the bushings.