I have a 86 TRX250R all stock except for uni filter and FMF pipe and silencer. I goes great in 1st to 5th but when I put in the 6th it won't pull it self. I checked the plug it looks fine. Any ideas

 

My 88 did the same thing when it was stock. I am 220lbs, and the bike hated 6th gear. Only after porting did it pull 6th gear.

 

not enuff power man....

 

If you have stock gearing and are not over 200 you should have no problem. Yes, the 86's 5th and 6th gear were geared diffrent but not that much. Also if you have big heavy tires that will do a number to the HP/torque !

 

I have the same problem, probably just geared to high for the power. I hardly rode in 6 in the dunes anyways. And weighing 215 doesnt help either.

 

I had the same problem when I got mine, the problem ended up being my tire size and tire. The guy had 22" inch balloon tires on the back and was impossible to pull 6th gear. What we did was we set the bike on a rack and went thru every gear
with it in the air. In 6th gear the tire size ballooned up so much and was extremey narrow and unbalanced. So I went to 18" MX tires and that fixed the problem completely

 

NOTE TO HUGHJAZZ: if you get smaller tires you will have to re-gear the bike a little taller then stock to make up for it, but the tire will be alot easy to spin and will also be lighter, therfor being easyer to pull 6th.....

 

there is this thing called re-gearing. buying a set of new tires is a waste, all though balloon tires is a waste of money for dune riding too unless your only going straight. go down 1 tooth in the front. have a 88 at 12 39, and works great in the sand. I weigh 225lbs.

 

Check your compression, it might be time to freshen up the top end. If the tires and gearing are stock it should pull 6th gear.

 

It has stock gearing 13/39 The compression is 150. It has 22 inch bear claws on the back. I think i am thinking of getting it ported and polish and shaving the head and putting a 45 tooth on the back.