Hi,
I am brand new to this forum and just bought two Suzuki LT250R quads ($500) are both originally owned and one has a running engine, which i will go through. I am looking for something to stuff in that will easily compete with the LT500R. I dont know what will interchange with these quads for i am new to suzuki's. Not to quads, just suzuki's. I can fab up almost anything so dont worry about skill level. Thank you very much and i am pumped to be on this forum.

 

If you can fab anything then stuff an 89 cr500 motor into it. That should get it to move.

 

Welcome to the forums.
"easily compete"...The quadzilla was prolly the fastest quad made. Not sure how well that's going to work for you.
Maybe a banshee motor with massive improvements.

 

The only thing you're going to be able to easily put in there to make it compete with a lt500 is a motor from a lt500 but it won't be cheap. Dirt bike motors aren't counter balanced and do not make good hybrids for any quad. I've read dozens of threads where people tried it and none were happy, they all vibrate so bad they rattle the bike apart. I've even seen guys isolate all the motor mounts with rubber and still couldn't stand it.

It's not a very hard swap to do and you should be able to find plenty of info on it as there are tons of them out there. The biggest part of it is notching the main tube for the spark plug to fit and there is some work on the lower right side for the motor mounts also. You're basically knocking 80lbs off of a stock zilla so you will need to lengthen the swinger by at least +2 which isn't hard if you're a fabricator and you'll probably want some wider A-arms.

The expensive part is finding a motor. You're probably looking at $1000 just for a decent motor because they are in such high demand, both from people wanting them for their zilla and guys looking to build hybrids like you. I've never seen anyone that built one that wasn't happy with it, they are screamers.

 

Those frames aren't the strongest or best handling, and 500 class power isn't going to improve that situation any. Still, you don't have much into it at present and if you can fab mounts and reinforce the frame it should be a good project. My suggestion would be to look to a modern 250cc or better dirtbike motor. Find a reliable builder and get it ported, polished, and stroked.

 

You will never get a 250 to run with even a mildly built zilla, I don't care what you do to it. Most people have never ridden a zilla and don't understand how fast they are. When dirtwheels first tested the 500 they clocked it at 80mph stock. Duncan took one and geared it a bit higher, put a pipe and reeds on it but never touched the engine and clocked it at 103mph. In stock form none of these new quads would touch a zilla in a drag race. The track is a different story, the suspension on the newer quads is awesome and you just can't get that kind of travel out of an 80's bike without spending big dollars.

My zilla isn't built much at all, I have a pipe, reeds and bigger carb but I barely touched the engine. The only port work done to it was by me and I just cleaned them up, it hasn't been ported at all and I'm only running 155psi compression. The only thing that has ever beat me in a drag race was a very well built banshee. I've raced several 450's, a trx310r that I guarantee you had 10k into it, A ktm 525 with a 540 big bore kit on it along with bunches of slower quads not worth mentioning and never even came close to losing to any of them besides that banshee which was built for the drags. I sort of expected losing to him.

lt250/500 hybrids are fast machines and there are a bunch of them out there, people have been building them since the 90's so there should be a lot of information available. There was a bunch of info on the old qhq site before it got shut down, seemed like someone was building one every week.

 

Thanks for all the info. I was thinking of doing a banshee motor, but i didn't know if that would work. Engine building is not my problem, i can get them going to maximum potential. It might not keep up with a zilla, but it still would be good enough for me. I could try and find a zilla motor, but that would be tough. Also is it true about how the dirtbike engine vibrates alot, never really heard of that before? I also thought about some time of snowmobile engine, could that possibly work?

 

I put an 04 GSXR 750 in my 86 LT250r frame. In a straight line it rips, but my 4 mil Banshee, 700 Raptor, and Renegade are easier to ride and more fun in the dunes. Nobody looks twice at the gixxer quad untill I start it and then it really draws a crowd.

 

I'm sure you could get a banshee motor to work, anything is possible. The question is how hard will it be? You have a few things to consider, are the twin carbs going to interfere with the rear shock and what about the airbox? You pretty much need an airbox unless you're just in sand. Another biggie is how the swingarm mounts, with the lt's the pivot bolt runs through the motor, not sure if it's the same on a banshee. You're also going to need custom pipes for it which won't be cheap.

A dirt bike engine that is not counter balanced will absolutely tear up a quad frame, even with rubber isolators, it's been done plenty of times. Google "cr500 quad" and do some reading, you'll see what I mean. The guys that you find that say it will work are the ones that haven't done it, read what the guys that have done it say. There's a reason most or all of the quad engines have counter balancers and it's the same reason the zilla motor is so expensive, there was never another counter balanced 500cc 2 stroke so there is a high demand for them to use for hybrid quads.

A counter balancer is also the reason most of the modern hybrid quads that guys are building to race are using the crf450 motor, it is a counter balanced dirt bike engine. You can do what you want but I'd do a lot of reading on hybrid quads first so you know what you're getting into and the problems you're going to face. As far as a snowmobile engine, I wouldn't. I've seen that done also and they always look like a nightmare with a giant clutch sticking out the side plus all the design/fab work to make some sort of driveline work.

 

richardw, have you seen that the quadracerHQ is up again?