Ok guys,
I have a friend that has a 86 Polaris trail boss 250. He wants to sell it and get the most out of it but it has a problem. You have to rev it up while holding the brake lever in and then real fast try to put it into gear. He supposedly had the primary clutch looked at and was told it was in good condition. Does anyone know what can be wrong? Or some suggestions on how to fix it? Could it be something in the secondary?
My brother used to own this quad so I will give you a little history. About 5 yrs ago, I was riding it and it threw the chain and broke the transmission case. My brother had it re-welded and we placed it back in and it ran fine for a little while and it has been doing this for about 2.5 years now. I will answer any other questions to the best of my knowledge.

 

Lee, sounds like the trans may be the trouble. Is it easy to put in gear without the motor running? If you can do it without being in gear easily, the clutch may be trying to go (too little belt deflection). with the motor off, move the wheeler back and forth slightly and see if it will go into gear. The synchros may be gettong worn out on that early model and in that case not much you can do except fix or replace. Eliminate the clutch putting tension on the trans, and you should get your answer. Hope this might help.Bubba

 

Bubba,
Even when it is sitting there idling, if you put the brake on it dies. I aggree about the synchro though as it is easy to put into gear with the motor off.

 

Lee, what do you mean by when you put the brake on it dies?The brakes are not tied in with the motor, only through the clutch with it in gear. Give me a little more detail on that one if you could [img]i/expressions/face-icon-small-smile.gif[/img]Bubba

 

Bubba, it is pretty much the way I said. The quad can be sitting there idling and you go to pull the brake lever and it dies. If I remember right the brakes are tied into a flywheel on the right side of the quad by the trans. Anyway when that flywheel slows down/stops the quad dies.

 

To me it sounds like your primary clutch isn't returning to it's neutral position. It's staying a little engaged (like it would if you rev it up a bit) turning the secondary clutch which of course would turn the tranny. So you have to rev it up to put it in gear or it will die right?? And if you hit the rear brake it dies right?? This all makes sense since the rear brake rotor is coming straight off the tranny. Take off the clutch cover and inspect the belt and clutch. I believe it's the primary clutch even though you said it was ok, they could have been wrong. Another thing could be a really short belt, but I doubt that one.

 

If it is not returning to its neutral position, is there something broken in the primary? What do I need to look for? Could it be caused by not getting everything lined up correctly?

 

Belt deflection first: 1&1/8 to 1&1/4. That will also tell you to a certain amount if something is bad out of align. The primary clutch spring coupled with the secondary brings the belt back to idle postion while riding. If it isnt staying in idle position, I think the primary is either binding becase of the teflon bushings worn out badley, the slider buttons missing or galded, the primary spring is broke, or a combination of any.Pull the belt off, remove the primary clutch cover, and you should get your answer. The 7/16 bolts torque to 90in lbs, and the main 5/8 clutch bolt torques to 40ft lbs. Bubba

 

Bubba,
What happens if the clutch buttons are worn in the primary or secondary? Also, are the clutches that were made back then the same as they are now?

 

The clutch design hasnt changed to speak of since then (none as far as I can tell you). The primary should be your focus first. The secondary could cause a problem, but the only way I would think would be if the clutch buttons were worn down so far that the helix was grinding on the screws and catching. I actually saw a primary clutch that was never serviced, and the slider buttons were so worn out that they came out and it gouged the clutch and broke small pieces off. Look at everything real close. Take the secondary apart if you feel it is necessary.You should be able to tell if the primary is all the way open, or if the secondary is all the way closed. Good luck,Bubba