Just got done rebuilding my 88 trx250r quad to "a-class" MX, agressive rec. riding.. only thing stock on my quad is the frame.. all leagers,lsr,nacs,works,durablue,ac,omf, fullbore.... everthing is finished as a rolling chassis except the ENGINE and AIRBOX. can anybody please help me find a good engine set up thats fast,reliable and can help me win races. not wanting to go anything higher than a 310 kit. looking for a new cyl., head, piston kit,gaskets,carb,pipe,silencer. your help would be greatly appreciated.. thanx, when finished ill have lots of pics... thanx again.....

 

Try LRD in Oregon, They build some pretty fast Quads, and make them reliable, too. They have engine kits all the way up too 350cc.

 

Actually their are 310, 330, 350, 370, and 410 kits available for the 250R from Nics Pro-X. AS far as reliability is concered and not wanting to go over a 310, your mistaken. I've heard, through alot of research, that the 330 is the most reliable motor of them all. Reason being a built 250 revs really high to make power and go fast. A big bore on the other hand does not rev that high, but they pull with a more torque. Yes a big bore produces more power that is harder on the clutch, crank, and gears you say. Again the clutch is not worked as hard by the rider because the revs are not a problem, thus its easier on the gears, so basically the gears and clutch end up lasting as long or longer anyway. Also the crank isn't usually s problem anyway.

The main things to watch for in a big bore kit is that the cylinder is much harder metal than stock, so they must be broken in well. Also how you have it built makes a big difference as it does with any size motor. I didn't go with the full race port on my 330 so the pistons would last longer. I've run mine for a season of racing and trail riding and I'm about to put my 3rd set of rings in without any troubles.

I like the 330 better than the 4-strokes I used to ride (Its actually been more reliable and much cheaper) and better than the 250 also. Its easy to ride and has a lot of power, making it fun to ride.

Oh yea, Last Rebel Racing built it, and in my first year of motocross, and first year on a 2-stroke (I had the first race easily won until the spark plug boot died on the last lap, and it was the first time I rode it other than break-in) I easily won the Quad B season championship with lap times as fast as the top pro on a Rotax powered Phillips Quad, and I also placed 9th at Red Bud National Quad Championship (My 5th motocross race ever) after being in last place due to a crash a little past half way through the main. So if that doesn't say that my mildly ported 330 is plenty fast, then I don't know what does. To tell the truth, I never once rode hard all season because I won every race by at least a half a lap, so I will be even faster next season when I actually have to ride hard in the A-class. My older brother even said that mine looks like it pulls harder than everybodies, even the pros which include 2 Rotax Phillips Quads, a CT 350R, and numerous other 330's and banshees. My friend on the CT 350R rode mine and even said that it has much more bottom end than his and pulls hard all the way up, so that's nice.

Hope this helps,

Sickman

[This message has been edited by Sickman (edited 11-27-1999).]

 

Matt,

Where did you get your Full Bore fenders? How much were they? Where can I see detailed pictures of them online? And finally, how satisfied are you with them? Thanks man!!

Lightninn
88 Honda TRX250R (wanna pic?)