Hi all,
am after any advice as to spocket sizes for running- zzr1100, car weight 420 ish prob 16" wheels would rather have get up and go rather than top end
cheers gary( have a 48 rear -standard front -think 17 any good??????

I'm told by those that know (hello Keith) that a 16 tooth front sprocket makes a significant difference.
Know a couple of people using ZZR1100 engine in mid engine RWD chain driven form. Will ask about sprocket availability.

I have a 16 tooth front and two rears - I think they are 54 and 46. I've done the calculations and the maximum speeds are 95 and 111 respectively.

I'm sure there's somebody on here who has a calculator spreadsheet. I'll send you mine if you want but it's a bit rough!

Wyn

Thanks Chris

I was concerned about this being low - I've checked the calcs a few times but think I must have got something wrong somewhere!

Here are the ratios and sprocket speeds.

Primary 1st 2nd 3rd 4th 5th 6th Final Rev Limit
1.581 2.600 1.842 1.500 1.333 1.200 1.115 1 11800
Sprocket speed 2871 4052 4976 5599 6220 6694


Wyn

Gary
Why didn't you ask me? I'm running 14:40, with the single engine you'll want around a 1:3 reduction so with 17 tooth front sounds like about a 51 tooth rear.
Russ

Chris - I think it's a 255/50 profile. The total diameter of wheel and tyre is approximately 450mm, giving a rolling circumference of 1415mm.

The 16/46 sprocket combination give a ratio of 2.875. Anybody fancy checking my calculations?

I've applied a nominal factor of 90% efficiency for rolling losses etc.

Regards

Wyn

Hi Chris

Maybe that's where my calcs are wrong! I've taken a physical measurement of the diameter of the wheel and tyre and that's the 450mm measurement. They are 13" wheels with a 50 profile tyre, so 450 (18" doesn't seem far off.

Regards

Wyn

Have you tried the calculator at http://www.westfield-world.com/gtc.html

You need to figure the diff ratio (big sprocket divided by little), it is set up for 5 gears not 6, and top rpm is only 8k, but it's a good starting spot. It helps me determine the correct gearing to get off the line quickly and still not smoke the tires too badly.

Good luck,
J