My son's the racer in the family, not me, I just wrench. We have a couple of quads in the "vintage" categories old 250x/350X conversions. One for flat track and one for mx. Yhe MX bike is only 365 cc's from the old 350 class racers, but it's a TC motor with some updates and my own custom intake. We just raced it in Harrisburg last week at "Motorama". It didn't set the world on fire, but it was my son's first mx race ever. (a seventh and a fourth in the heats) power was NOT the problem. In a straight line this old 365 held its own against the 440's and then some. Pulls about 45 hp. (honest) at the motor.
This 250X frame is the same as your 300ex frame. I was curious how you got 400 ex shocks to mount. We run triple rate 16" Elka's, made for a 400ex on 400ex +2 houser A-arms - they wont mount to a stock frame.
Also my son rides a friend's 300ex regularily (while the old 350 x is getting blood) not very close in the power department. The 250x frame does not jump like a 400ex or 250r with it's shorter wheel base. If you really want to compete get a bike with newer geometry. The old 250X frames aren't bad for flat tracking, but are not equal to the "r's" or 400 ex frames or their derivitives for mxing. Not to say that a good rider on a well suspended 300/250 frame can't compete, but you better be in shape. Don't see a lot of Walsh, Laeger, Houser, Lonestar or Fischer 250X derivitive frames out there.

 

I agreee with TRXter on this one.

If you are outrunning your buddies on 400EX's with your 300EX, it's because your friends are lousy riders. That has a lot to do with it.

Yeah, on a straight away, it's a no brainer. The 400EX will win. I own a 400EX which I've installed a 440 kit, put in a cam, different air box, different carb, Big Gun complete race exhaust system, titanium valve springs, and some porting and polishing.

I ride with 3 guys that have DS650s, 1 has a 660R Raptor, and 2 have 400EXs. When racing on an obstacle course or through the woods, I generally finished last (before I made my upgrades), mainly because I'm by far the most inexperienced rider. However, one of the 400EX riders that I ride with has been riding for years, even in competitions, and he beats us all...and his is all stock. End of point.

And as far as the debate over whether the 10mph or so difference between the 300EX and the 400EX is worth $1000, 2nd place sucks!!! I didn't upgrade my quad just because I want to go faster. I just hate losing.

Being #1 is everything. Second sucks!!!

 

It's not just 15 mph of top end it's faster in every single gear and has more low end torque because of it's higher compression and bigger engine. Like the rest of you already stated it has a better frame design more suspension it's wider for cornering stability and has 115 more cc's. I think the tight trail argument is lame SparkyEX's Cannibal is almost an inch wider than a stock 400ex and he has no problem in tight trails at all. I've rode in many places and I've never seen a quad trail so tight that certain quads couldn't fit down it only some dirt bike trails. In one of the wheeler mags a few months ago they built up a 250ex and took it to the track and entered it in the beginner class and it did well. Why? because the riders they used weren't beginners and they admited it. Except for in a wide open flat area a better rider can out ride someone on a more powerful quad most of the time.

 

Everyone that thinks the 300ex is better than the 400ex , has never ridden a 300ex.

 

I mean 400ex, With $1000 you can have a 440 kit , with a pipe , cam, filter on the 400ex , so who r u trieing to kid by saying the 300ex is better.

 

EX master just shut your mouth you dont know what your talkin about we never said the 300 was better then the 400. if you spend a 1000$$ on a 300 we said it might be able to run with the 400 so next time read it before you speak

 

oh ya and i have ridin a 300ex hahaha god bless you ex master

 

If you spend 1000 dollars on a 300 you could have bought a 400

 

this is a good arguement.

 

You are right with the extra 1000 you could have bought a 400 but for 14 ill stick witha 300 maybe in a few years ill get something bigger