motor sprocket

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RooDog
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Re: motor sprocket

#16

Post by RooDog »

What's the end game here, a high revving stump puller?
kitabel
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Re: motor sprocket

#17

Post by kitabel »

1 tooth on trans is equal to 3 on motor
Not even close, how is three times 16 equal to 28?

The math already done on my site: http://www.victorylibrary.com/tech/gr-45.htm
You won't be able to pull 5,000 in high gear without serious engine work, but 4,000 is fairly easy (multiply the speed shown by 80%).
JUGPAM11
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Re: motor sprocket

#18

Post by JUGPAM11 »

Do the math? Thinking of trying some different wheel and tire sizes so may need to do some more figures. Hope to end up with tires with same diameter as 5.00-16. So what is the formula for the over all ratio? May need to come up with different sprocket combo to make it work out like I want. 16 in donut spares with 4-1/2 in bolt center may do the trick. Anyone try that? Thanks for all your help.
kitabel
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Re: motor sprocket

#19

Post by kitabel »

Final drive ratio = clutch sprocket × axle sprocket ÷ engine sprocket ÷ transmission sprocket (if belt, substitute pulley teeth, duh)
59 × 37 ÷ 30 ÷ 17 = 4.28:1
Ratio in intermediate gear: above calculation × actual ratio
4.28 × 1.57:1 (45 2nd gear) = 6.72:1

MPH = tire OD × RPM × .00295 ÷ final drive ratio
26" × 4,000 × .00295 ÷ 4.28 = 71.68 mph

There are 10 others, and they all do the same thing. For most bikes, 26" is almost assumed.
A 16" donut is very likely a low profile (aspect ratio) and will not be 26" tall even if 5.00" section width.
panhead
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Re: motor sprocket

#20

Post by panhead »

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