old speed bike

I use a 5:1 pocketbike transmission. It connects to an 11-tooth engine sprocket to 63-tooth chainring. Using 8mm chain for this connection. Then I use a 30-tooth chainring sprocket with bicycle chain. This connects to 11t-34t rear cassette. I have a shift kit, and my first gear is 32.45:1.....

In 8th speed, the gear ratio is 10.5:1.....for high speed.

You do not have a 5:1 transmission, so producing a good working gear ratio is not easy. Using 8mm parts makes it easier to make gear ratio than bicycle chain or 415 chain. Maybe you can use 6-tooth engine sprocket to 15-tooth intermediate step at the jackshaft(axis). Then 10-tooth to 72-tooth on wheel hub.

15/6 = 2.5...
72/10 = 7.2.....

2.5 x 7.2 = 18:1 gear ratio.....good starting point.

Find a rear hub for disc brake. Then drill 72-tooth sprocket to bolt onto disc brake flange.

That should work.:geek:
 
I have ignored and I bought a gear box, with much pain in my heart and pocket as the cost of shipping from use are high.
if this kit works well enough implificar hope the matter.
we'll see

Greetings
 
Your English is hard to understand. Do you have a friend who can help you
write what you need? I mean no disrepect. I just want to help.

This is what I don't understand:

"implificar hope the matter"

Comprendo...I hope this simplifies the matter.:unsure:
 
Last edited by a moderator:
google translator

Your English is hard to understand. Do you have a friend who can help you
write what you need? I mean no disrepect. I just want to help.

This is what I don't understand:

"implificar hope the matter"

Comprendo...I hope this simplifies the matter.:unsure:



sorry man.

my english is elemental an d i use the translator (copy and paste) and if you don,t be care writting the translation is wrong.
sorry again.


i follow your example and i bought a gearbox.

i mount it when i recive it. i hope simplify the final result



saludos
 
Bueno.

The gearbox is simple. Did you mount it on engine or bicycle?

Do not forget to put oil in gearbox.

You can use bicycle front sprocket with 44 teeth to connect to 10-tooth gearbox sprocket. Use bicycle chain.

The inside front sprocket has 32 teeth. Use bicycle chain to connect to rear derailleur.

It is cheaper if you do not use pedals, but the front shaft might need to be widened to line up the 44-tooth sprocket with engine sprocket.
 
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