Best sprocket to use on 29" bike

[lukecanna]

Hi everyone,
I have just put my motor on a 29" bike (already run in) and I would like to know it it is worth switching to a 36t for higher speeds. is it alright to do this with the bigger wheel or should I just keep the provided 44t

 

[FurryOnTheInside]

Hard to say, based on basically no information lol.
I think ultimately only you can decide what size sprocket suits you.
Some things to consider are:
How important is acceleration or hill climbing?
How important is reliability or fuel economy?
What type of terrain and road surface will you ride on?
What is your total weight?
What tyre size are you using?
What other modifications have you made to the kit?
What kit did you use to begin with?

I'm using a 42T on the same diameter rims with 32mm (1.25") tyres, and I think it's a good size for my fat arse and the balance of factors that I need. I have modified my engine for a little better low end torque, but it was a generic no-name cheapo engine kit that I started with.

 

[lukecanna]

Fast acceleration not to worried about.hill climbing as that's what the pedals are for. Reliability is key and I'm not worried about fuel economy I usually ride on bike paths so far terrain not usually anything out of the norm. I'm only 60kg. I have a 1.95" tyre. my engine is stock except for spark plug, billet 13mm inlet and exhaust mods.. same with you I have a generic China kit

 

[FurryOnTheInside]

Fast acceleration not to worried about.hill climbing as that's what the pedals are for. Reliability is key and I'm not worried about fuel economy I usually ride on bike paths so far terrain not usually anything out of the norm. I'm only 60kg. I have a 1.95" tyre. my engine is stock except for spark plug, billet 13mm inlet and exhaust mods.. same with you I have a generic China kit

Reliability: it is often said that high RPM is the killer with these engines (and lean condition too, of course).

The 36T will certainly help you to keep the RPM low; but I have doubts about the 36T actually resulting in a higher top speed unless you modify the engine for more torque.
It will also kill acceleration somewhat, unless you modify the engine for more torque.
I would consider a 41T, and some modding too.

And to be quite honest,, if reliability is key, top speed shouldn't matter!

 

[crassius]

agree, try a 41T first as no two motors are the same - 36T is often problematic

 

[lukecanna]

how

Reliability: it is often said that high RPM is the killer with these engines (and lean condition too, of course).

The 36T will certainly help you to keep the RPM low; but I have doubts about the 36T actually resulting in a higher top speed unless you modify the engine for more torque.
It will also kill acceleration somewhat, unless you modify the engine for more torque.
I would consider a 41T, and some modding too.

And to be quite honest,, if reliability is key, top speed shouldn't matter!

just curious as to how I would mod my engine for more torque ?

 

[FurryOnTheInside]

how

just curious as to how I would mod my engine for more torque ?

How you would is up to you, lol. How I would is something like this:
https://motoredbikes.com/threads/bush-track-29er-how-to-make-it-climb-hills.52522/#post-460602