i can get a 250ex and i will have $550 to put into it how can i make it faster than a 300EX, just on top-end, what about a cam and a big gun exhaust?? help

 

why not just get a 300ex?
you will probably have to wait untill someone makes some preformance upgrades, then you still might not be able to top the 300.

 

You're going to have a difficult time, the 250ex is a shaft-drive.

Even if you modified the engine, you would only make improvements in acceleration. Since you don't have any sprockets, you don't have any way to translate the increase in power with an increase in speed.

The only way I can think (short of changing the gearing inside your motor) of getting more speed out of your quad is: modify your motor, then
a) replacing your rev limiter with one that allows your quad to rev higher and/or b) getting larger diameter rear tires.

It will most likely be necessary to modify your motor; I know the recon's motor (almost the same as the 250ex) can't reach the rev limiter in 5th gear w/ a 105 lb rider. Therefore, putting a higher reving limiter or larger tires on would most likely do nothing (may hurt power w/ larger tires).

I'm not sure how much of a speed increase you'll get - there are simple formulas others have posted on this website that will allow you to calculate top speeds (given gear ratio, tire size, rpm's, etc.).

ogre

 

My cousin hit 52mph on my 250ex and that is as fast as a 300ex. The rev limiter kicked in twice and my cousin wheighs 150 pounds. If you take the airbox lid off and the spark arrestor off it will have a decent increase of tork.

 

If I were you, spend the extra money and buy a 300EX. My wife rides the EX now but I bought it in 1995 and have no problems with it at all. I recently just replaced the clutch for the first time. I would highly recommend that you just buy a 300EX even if it is used. I put that EX through hell and back so I'm confident that a used bike would be equally great as long as the oil was changed every 30hrs.

 

The shocks on the 250EX are non-adjustable, you can't change the gearing. Why waste money and time trying to make the 250EX something it's not? Just buy a 300EX, if that is the type of quad you want.

The 250EX is a nice, well built sport quad. Learn how to ride it stock, if you are any good, you can then trade it in on a higher performance quad. Why are you wondering about modding a non-mod-able quad when you are getting a Raptor?

 

my recon will almost eat a 300ex

 

Get bigger tires (since you can't play with sprockets)...or/and revv higher (no airbox lid, better air filter, bigger carb <- not mandatory, and freer exhaust).

Or quite simply get the 300.

 

how well will that little push rod head take to high revs?

 

A stock recon will only do 38.5 mph.