I have a Raptor 700 with (mods listed in Sig) i reacently put the Kenda Knarly 21-11-9s on it and i havent had a chance to try them out to see if i have lost any power compared to the stock tires or if i have gained top speed. But what i was wanting to know is I am thinking about buying a 15 Tooth front sprocket for it and i want to know how much top speed i will have and how much excelleration and power i will be loosing? Thanks Mace

 

Optimal gearing is complicated. Taller gears may improve acceleration on a bike whose torque curve is prone to create excess wheelspin. If you have bike like a Raptor 700R that makes big torque very early, it will more easily break traction which of course slows forward momentum. Taller gears will slow power delivery but if mated to the right terrain and tires, it will improve traction which will mean more of your motor's energy will be converted into forward motion.

Taller gears are also more likely to improve performance on the flat and decrease performance the steeper the hill is. The reason is found in reduced RWTQ due to leverage. This means that whatever sum of weight and friction your setup has with you on it will make a more profound difference the steeper the incline. With lower gears, incline will make less difference when compared to running on the flat.

Ron

 

15 tooth will give you a lot of top end but it will take awhile to get there. You won't have the same pull off bottom with a high gear like that.

 

Not totally sure, but from my experience with raptors, they are already geared extremely tall for the exact reasons DSNUT was saying. With the below information used for calculations I found that a stock 660 was gearing limited at 92.2 mph!!!!!! However, it will never see that due to the lack of power, weight, and drag. Stock they are about 74-75 mph.
Keep in mind this is information for the 660, NOT the 700. But I am willing to bet they are pretty close, and that for argument sake, the 700 is geared just as tall, if not taller than the 660.
Go ahead and try it, see what happens. What are you going to be out if you dont like it, .....$15-$20!!!!
Transmission 5-speed, Reverse, Manual Clutch
Primary reduction 71/34:2.088
Secondary reduction 40/13:3.076
Gear Ratios 1st 2.428:1
2nd 1.526:1
3rd 1.238:1
4th 1.047:1
5th .904:1
Reverse 1.750:1
9000rpm limiter
20 inch tires

 

thanks for all the info. I guess i will find out when i put the sprocket on. I cant make up my mind if i want to gear it up or not [img]i/expressions/face-icon-small-tongue.gif[/img] I never though about the gearing getting rid of my wheel spin off the line. But the new tires i have might have helped that alot. I wish the weather would get nice again so i could find out. Jamie Mace

 

When im riding the flats in the desert, I have my 5th gear maxxed out with the stock 20" tires. A 15tooth sprocket would work for me really well in leiu of a 6th gear.

When im in Glamis the sand takes more power, and i would not even think about using a 15tooth sprocket, as 5th is not used unless im in a wide open bowl or section of whoops.

Youve already increased your gearing by goin to 21" tires. Try it, and you may find that is all the difference you need.

 

On the flip side, I put 22's on mine, and in the woods trails here, the thing was about unridable, it was so overgeared. A switch to a 13 front made a big difference.

 

Excellent example Lotus.