Hey I was just wondering what I can do to make my Lt250R faster as you can see I don't have alot of power mods right now? Looking for all the help I can get.

 

get it ported.

 

85-86 motors aren't as fast as the later LT motors. They don't have a 6th gear or a powervalve so they can't make the same power as a built 250R or 87-92 LT motor. With the stuff you've got it should rip pretty good if it's running right.

 

It runs even with a stock z400 right now I am looking for a little more power to be able to beat a z-400 easily. I was thinking about a bigger carb and maybe getting the head milled alittle bit. What do you guys think i should do i saw a performance carb on ebay the other day but it said it was for the 87 up models why won't it work on the 86s?

 

The 85-86 and 87 and up motors are completely different. A bigger carb will only make more power if your engine is ported to accomodate a greater amount of air flow. Also, as a rule, larger carb = more top end, smaller carb = more low end. I've heard that the 85-86 motors are tricky to port because it's easy to lose the good bottom end torque they have stock. I've also heard that these motors can be made fast but they will be peaky (not a very broad powerband).

The LT500 motor is a common swap that the real go fast guys out west put in the early LT's because they're much lighter than the later LT or Zilla frames. That's the route I eventually plan to take.

 

Increasing the compression by milling the head will def help, but over a certain amount (170-180 psi depending on your squish angle) you'll have to run race gas to prevent detonation.

 

i had a 86 LT250R and it ripped. i had it ported for top-end, a 38mm Carb, Reeds, and the weisco piston really made the biggest difference IMO. i also had the head milled. i had all my work done by trinity and i reccomend them highly.

 

the cheapest way to get the most noticable power for the money is lighten the flywheel!! $75.00 through duncan racing. but dont let just any shop do it, because the might not get it ballanced evenly.

 

If you got a few bucks, let duncan motors racing port polish it. get a new carb and paul turner exhaust.

 

A cheap mod that I always like is a set of Boyesen reeds, milling the head will give you better low end and midrange but not neccesarily more top end. If it's already got the power to pull 5th all the way through and you want more top speed step up one tooth on the front sprocket. If it's not jetted correctly there is more power to find there as well. Since you are limited on your pipe choices, porting and a bigger carb. I used a 35mm Mikuni TMX carb on mine that I got off ebay for 30 bucks, since it was still small it has good throttle response but because it's a newer design than the stock TM it has a higher peak flow rate. With stock porting I wouldn't go larger than a 36mm as you will lose bottom end power, I know this from experience.