baja minibike engine dies when under load

[gvfc2]

if anything brake is alittle to loose. barely any stopping power there. how to test my bearings?

 

[B man]

if anything brake is alittle to loose. barely any stopping power there. how to test my bearings?

well an easy way. is to jack the bike up and spin the tires to see how easily they spin. then try to roll the bike on the ground and you just kinda got to feel the drag.

And have you taken the tires/rims off and put them back on? cause if you over tighten them back on that could be your problem.

 

[gvfc2]

ok so pretty much just loosen it and it might reduce drag alittle

 

[Bluethunder3320]

i dont think its the bearings. they should be tight as can be. because the spinning should be all on the ball bearings not on the axle

 

[gvfc2]

so just replace the bearings? because it was owned by some neglectful people

 

[Bluethunder3320]

i dont think its the bearings at all. chain too tight?

you could take the chain and brake caliper off then turn the wheel and see if it still has resistance, if it does than the bearings are the only thing left.

but i think its highly unlikely the bearing would cause resistance like that unless it blows apart. the bearing is at the very center of the wheel, it would take a lot of force to overcome the outside of the wheel against the road

think of it like trying to loosen a bolt by hand

 

[gvfc2]

well im sure its not the chain. over 1/2" play at its tightest

 

[tundrabeagle3]

well an easy way. is to jack the bike up and spin the tires to see how easily they spin. then try to roll the bike on the ground and you just kinda got to feel the drag.

And have you taken the tires/rims off and put them back on? cause if you over tighten them back on that could be your problem.

I agree I had the same problem on my mini and it was that the chain was too tight and the brakes were tightened to much. I had a hard time pushing the bike and when I stopped on the gas it quickly slowed down. I would try loosening the brakes a little and doing what B man said it is also possible the nuts holding the wheel on are tightened too much. Also you could try putting some wd 40 on the wheels and chain. And if that doesn't work you could try soaking your bearings in transmission fluid. It works wonders on dirty bearings because of the high detergent content in the oil . It is normal for it to slow down a little when you let off the gas because it is a four stroke it is called engine braking.

 

[gvfc2]

i know it slows down when let off gas. but so much so to kinda slide me forward in my seat?

 

[B man]

i know it slows down when let off gas. but so much so to kinda slide me forward in my seat?

Is it easy to roll? Feel any resistance? Sometimes tires can do this.

 

[gvfc2]

yes its very easy to roll

 

[Bluethunder3320]

I agree I had the same problem on my mini and it was that the chain was too tight and the brakes were tightened to much. I had a hard time pushing the bike and when I stopped on the gas it quickly slowed down. I would try loosening the brakes a little and doing what B man said it is also possible the nuts holding the wheel on are tightened too much. Also you could try putting some wd 40 on the wheels and chain. And if that doesn't work you could try soaking your bearings in transmission fluid. It works wonders on dirty bearings because of the high detergent content in the oil . It is normal for it to slow down a little when you let off the gas because it is a four stroke it is called engine braking.

engine braking is when you have the clutch engaged. and it shouldnt do that with a centrifugal clutch because when you idle the clutch is free spinning. but maybe if the engine rpm doesnt let down quick enough it will drag a little

 

[gvfc2]

well if it still happens with a new engine (whenever i get it) then i will deal with it

 

[gvfc2]

ok finally got a pic of the new color

 

[gvfc2]

when i upgrade to the 6.5 predator what TC should i get?

 

[B man]

comet 30 series. or the tav2.

 

[Bluethunder3320]

get the PMR motor mount too. you can skip it and drill your own holes but then you cant adjust it. well worth the $40 i think it was

 

[gvfc2]

i will go with the pmr mount dont feel like going much drilling

 

[gvfc2]

ok so i got the PMR engine mount and now about to buy a predator 212cc engine. got a 3/4 12 tooth clutch(will upgrade to TC later)

what exhaust should i get? im going to taking this camping with me so i would like it to be quieter than a dirtbike. if anyone can point out some cheap mods for this engine i would be greatfull

 

[souperman000]

cheap mods - remove governor, aftermarket airfilter, rejet carb...just to name a few.

Do a quick search on the forum and the internet about exhausts. There are quite a few custom exhaust biuld threads around here.