hey guys. so i bought a 1991 lt250r and i love it. It hauls ***, but my dads atc 250r kills me on the take off. He has his atc stock except for the fmf powercore exhaust and silencer. My lt250r is bone stock completely. What can i do to make it faster without sacrificing too much reliability? Thanks.

 

In general trikes will be faster as they have less weight to push and less rolling resistance as well. However, that Zuk engine is capable of some insane power. I would look at the National kits from CT. I had one and it was crazy fast, yet not as "peaky" as some I have ridden. That is what I would do to it anyway.

 

What does the kit include? i know it comes with piston and a ported head am i missing anything? And what would be ur best recommendation for an exhaust?

 

best is to check the website. The ports on a 2 stroke are in the jug, not the head. I like the FMF Fatty, power was pretty balanced on that engine. I am sure CT has a nice pipe, or you can get a Paul Turner from DRI, etc. The PT High Rev was a handful on the LT, but I have one on my current TRX250R and love it. Since the power delivery can be manipulated so much with the pipe, best to get inpt from the guy doing your porting etc.

 

Do you want it faster out of the hole or top end?

I'd start with a good pipe and reeds.

Doesn't this motor come with a power valve cylinder?

 

I want an average increase of power in all areas. be low or top end. It doesnt have to be a huge, drastic increase. something not to peaky yet with a small sting. once i save up money i'm goin to buy an fmf fatty and then work my way toward a ported jug with a little more aggresive piston. And it is power valved. What exactly do the reed valves do? Is it hard to upgrade? i have also been hearing that the lt's have a weak chassis and are prone to crack easily, is it true? Thanks for all the help guys.

 

I just bought myself one of these bikes and mine is definitly NOT stock, I have an FMF Fatty, Carbon Fiber Boysen reeds, Uni air filter (No air box), 65mm piston pluss the head has been ported and polished. Honestly, my bike scares me rite now! I moved to this from a raptor 250 (just started riding 6 months ago). I can pull wheelies in the first 5 gears but have not wanted to try it in 6th.

The first couple years had some issues, 1985 - 86. 1987 was the year of change for these bikes, power valve motor stronger rear swing arm and frame. along with some other minor changes. Overall from all my reading, I am told V-force reeds are awesome on these bikes.

 

@Durby thats awesome. I upgraded from my old 200x but i'm a pretty big guy. I bought it for a pretty good deal($900) and it is in pretty good shape. It is a really good quad but i just want a little extra push to be able to seriously compete with other quads like 450s. Do you know what the stock size for the piston is?

 

well I am 235lbs myself, I believe the stock piston is 67mm bore and they go up from by .5 mm to 69.

 

Have you raced any other motorcycles? like suzuki 450's or banshee's?