motor builder for a lt250r...

[800screws]

i know this is a 250r forum, but alot of u guys are ex-racers who might have some experience on this matter...

on the 250 engine, which is the better top end to use for mx? the 87 or the 88 and up? i know the deal for the 500, but what about the smaller motor? it would be ported, piped, etc....

and which builder do people recommend for doing the 250? i'm pretty picky, so i would like to use the same stuff for the whole thing...pipe/porter combo...i know ct and duncan do complete kits...probably led performance also...

[250rPRIDE]

i would go with a 89 honda motor :devil:

[headache]

i believe that the 87 has the most potiential for power. The reed cage and intake area are huge. However the 88 and up run good too. The proper port to pipe combo is what really matters...

[05LSR250R]

Three years ago I did a ground up restoration on my foremans 91LT250R. He had all the motor work done by Duncan Racing from carb to pipe. I believe it was just the "National Kit". They were very helpful and did an awesome job with the motor. Im sure they would know which years are the better ones for workin big power out of the motor. His ran like a raped ape!Hope this helps.

[1promodfan]

My cousin has a '88 LT250, he had some port work done by a guy in the mid-west. It runs really good, he just has a few goodies on it.....FMF pipe, Boyesen Rad Valve etc. I can get you some info if you're interested. Have you tried the quadracer forum? I know there is some great guys over there.

[800screws]

thanks...i wish there was someone other than duncan....just because they are so expensive...

[250rPRIDE]

no for real my best friend drag races a lt250r and he has 6 or 7 cylinders for it and he uses the 88 up he tryed to diff 87's and they didnt work as good as the newer ones, but it is stock bore and it runs i had 3 different honda r's and he out run them all at the strip :mad: not by much a tenth or two but always beats the 250rs and most banchees.

[800screws]

really? i would think for drag the 87 would be the way to go....

[312R1]

I don't know if there still open or not but back in the day I had a 91 LT250R that my dad sent the engine out to Klemm Research and when I got it back it was just to much for me I was 12 at the time so thats when I switched to the 250R.

-Steve

[250rPRIDE]

yeah honest he had the same guy do the same port work on the 87's and they didnt work and he also tryed the yz piston because you can hide in on a lt250r to look stock and he went back to the standard bore new style, dont know why but it works like you wouldnt believe, ive been racing it for the past year, and it doesnt fell right beating my buds with a yellow machine:( haa.
but it has a turner pipe with a 41.5 carb into a ftz ported rad valve drag port work and a k and n inside a stock airbox, only 160 lbs compresion on 92 pump gas and ams oil, i should know i bought and mixed it all summer. ha
damn lt250r ha must be the power valve, idk?????

[fulltiltrider]

The 87 cylinder is the best for big power. Problem is, you need to go very wide on the exhaust port to get the gains. There is so much more intake area that you need alot more ex.TA to match it up. Now for a mx port Id go with the 88+. You can get a more linear powerband out of the mellower port layout

[woodsracer144]

im geussing you didnt get much for hits on the quadracer fourm?
are you trying to keep it with a stock cyl? i wonder how a old rm would work on there like they use the polaris 400L 's on the 250rs and the cr cyls as well... i've heard that klemm was really a good set up... too bad Dr. Q didnt have a set up for this like he did for the zilla...

i know that sparks made a really good trx motor... i wonder if they ever touched a lt?