Gear ratio

[qcitytile]

I need some help with what gearing to run. Got a scrambler 90 mod. We are using 20 front and 28 rear. Wondering what others use. Thanks Joe

[qcitytile]

Any suggestions?

[etondaddy]

We always used 19-28........it's a good all around combo.


Mike Kozura

[qcitytile]

I need help with rollers . I am using all 8 gram rollers just to get any kind of low end. Every body I talk to tells me thats way to much weight, but if I drop to 6 gram its very sluggish and motor is reving very high but not wanting to take off. We are using 19t and 30t sprockets and 1500 torsion spring with 2000 rpm shoe spring on a frc clutch. Please help any ideas is this common.

[dericsdad]

Something is definitly not right. What other mods are done to it??? Pipe? Carb? CDI box?

Could be a front variator issue... you should draw marks on both variator faces where the belt rides and run it, this will tell you if the belt is shifting out all of the way. Are the rollers/ramps in good shape?

With a pipe, 24/28mm carb, and unlimited cdi you should be good with 27-30 grams total weight. could use all 4.5's, 4/5's, all 5's, 4.5/5's... just need to see what works best.

Dan.

[qcitytile]

We are running unlimited cdi, hetrick pipe, and 28mm carb. Mallossi variator seems to be in good shape and I got a lot of new rollers. I started at 30 grams and tried to tune from there and the lower I went it got worse then I started going up and the heavier seemed better. I talked to the Hetrick guys and they said sometimes these motors put out a lot of torque and this is what happens, but everybody else says something else is wrong , but I cant figure it out. It runs ok, but a local Cobra 50 keeps up and I dont think thats ok enough. Thanks for the replys

[quadracer707]

Originally posted by etondaddy
We always used 19-28........it's a good all around combo.


Mike Kozura

Is there anywhere you can get different gears to fit the trx 90, right now I have a 13 front & 48 rear, but cant seem to find anything but those gears to fit the trx 90. I know most have complete different rears but was wondering if there is a manufacture out there to buy from.

Ken

[etondaddy]

Well the 19/28 was on the E-Ton. We run 14/48 on the Honda. I was thinking of going to a 49 rear to try to get him out of the hole better......... And out of the corners until he learns how to ride the Honda…

We have a DRR axle under the Honda and I get my gears from Rebel.

I found this stuff on the Internet and am driving my self nuts with the positive and negative percentage change going with different gear ratios. lol

Rebel gear will made you anything..... and with southern hospitality.

I hate diggin up those pics....it don't look that that no more..... all ready......

http://www.rebelgears.com/
http://www.dropbears.com/u/utilities/sprocket.htm
http://motorcycleanchor.com/motorcycle/how_to/mc_sprocketmath.html


Mike Kozura
http://i58.photobucket.com/albums/g278/etondaddy/000_0152.jpg

http://i58.photobucket.com/albums/g278/etondaddy/100_1210.jpg

http://i58.photobucket.com/albums/g278/etondaddy/000_0145.jpg

[qcitytile]

Alright I marked lines on the variator and with all 8 gram rollers and the belt travel is about 1/8 inch from edge and as I go down in roller weight it gets further away. Would the rear cluch cause this. It is fairly old, but it does have new torque spring and shoe springs. Is it possible motor is weak. It sounds really good and its at 180lbs compression. I'm lost

[Nichols Atvs]

The polaris predator 90 uses a 788 belt and you can try that drr uses a 787 belt. Sounds like you maybe using a 780 try going a longer belt like a 787 or 788 you dont need that much weight thats too much you should be down around 4.2-4.8 ,8 is way to heavy.