jed250
I pluged your numbers in by selecting the create my own option. I didn't know all your info so these results are bogus. but this will show you what you need to do. Make sure you enter a zero in the gears that you don't have.

Primary Gear Ratio:2.407 Front Sprocket Size:14
Rear Sprocket Size:38 Wheel Diameter:20

1st Gear Ratio:2.389 = MPH 32.712
2nd Gear Ratio:1.609 = MPH 48.936
3rd Gear Ratio:1.179 = MPH 66.784
4th Gear Ratio:.906 = MPH 86.908
5th Gear Ratio:0 = MPH 0
6th Gear Ratio:0 = MPH 0

RPM: 7500

 

is that calculator messed up? it says a banshee tops out at 68, but a z will go 69.

 

Hey aren't these speeds only for a perfect world, ie without wind resistance or friction?

 

Thanks to everyone who helped me out[img]i/expressions/face-icon-small-smile.gif[/img]

Anyways, the problem for me is that...I don't really know what my Engine revs at. It also uses a shaft instead of a chain and sprockets...

 

Shouldn't Wind Assistance also be considered? I mean, if your driving and the wind is blowing from behind you, then I would think it would help move the bike ahead...

 

jed250.....your finald drive reduction of 5.684 works out to be 56 tooth rear and 10 tooth front sprocket. Or another other cobination that gets you 5.6. In this case 56 devided by 10 equals 5.6 and that is close enough for now. so If you have 22" rear tires your results are as follows.

1st 17.5 mph
2nd 26.0 mph
3rd 35.6 mph
4th 46.3 mph

Since you have a shaft drive all you can do is change tire sizes I would think to get speed changes. Other than motor mods any way. [img]i/expressions/face-icon-small-wink.gif[/img]
Gearing calcs are only a guide they are by no means exact. For example I know for a fact on black top no head wind that when my DS was stock it did 81 mph. At least that is what the truck paceing me said we was doing. A stock DS is suposed to only do 75 i believe according to the gear calculators.

 

Eaglecollector: Thanks for the info. Although I'm not exactly sure that that would be the approximate speeds. Im thinking my bike revs lower because it's a utility. Top speed is about 75KMH so I'm not all that sure if it is that fast.

What if I change my shaft? Is there any way to modify it to gain torque or gain top end?