need advice to mount sprocket on chainsaw (no welder available)

[mat_man]

Hi NormO
First hand experience is always the best. Was this on your "first build" bike
below? What was your primary reduction on this bike? Looks like a gearbox,
but not the common 5:1. Great looking bike, by the way.

Thanks

Lowracer has V belt drives that should work well: (2nd Pic)
I think he has some older designs with a idler pulley clutch.
Guess you could drop the motor with a scissor lift for a clutch.

Tanaka PF-3300 V-Belt Drive w/Power Pipe
http://www.motoredbikes.com/showthread.php?36996-Tanaka-PF-3300-V-Belt-Drive-w-Power-Pipe

 

[NormO]

Yes that was my first build. At least with a chainsaw anyway. There is no gearbox. what you see there is just a plastic chain guard. 6 tooth sprocket on the clutch drum that was shaped with a bench grinder and then a dremel. The main gearing on that bike has since changed. it's now a 52 tooth sprocket (was 48) running from the engine. the sprocket behind it is still 9 tooth. i also changed the rear cassette to an 8 speed cassette. 1st is now 34 tooth(was 28). 8th is now 11 tooth(was 14). Just want to say thanks to 5-7 Heaven for the gearing suggestions and anyone else who gave suggestions. It went from sorta lazy to a snarling beast with claws. I'll mention again i'm not a lightweight although i'm a little lighter than i was. I'm only 200lbs now. I just want to mention that shaping the clutch sprocket will not work if the drum has a "floating sprocket".

 

[pocdragon]

Who needs chain drive anyway.

the stock clutch on the chainsaw will NOT beable to keep up with a bike and rider

you dont have pedals so you will need to gear it to pull from a start


just set up a friction drive, that motor will scream CS motors are killer

no clutch or chains needed

 

[NormO]

Why bother with a DIY setup at all ? There's a ton of kits available with just about any configuration a person could want. Just buy one of them, put it on and go riding.
Why buy an econobox car put $100,000 into it when any muscle car out there will eat it for breakfast? You'll end up spending less money to boot.
BTW, thanks for saying that a month of hard work and calculations was wasting my time pocdragon. Is really nice when someone calls your creation a piece of s**t. I could have kept the pedals but there was no point. It's an off road machine only anyway. Pedals would have caused hang-ups. I'm sure Sick Bike part would have sold me a freewheel and sprockets.

 

[mat_man]

Who needs chain drive anyway.

Judging from NormO's bike pics, He rides in very hilly country. I would think
his multi-speed design would serve him well. Almost all friction bikes are one speed.

Friction bikes tend to have problems in wet environments.
It might be difficult to find a dry spot to change to a rain roller
in the woods. Rain rollers tend to eat tires faster.
Friction bikes tend not to work as well with knobby tires that he might prefer for dirt trails.

All designs have trade offs.

I do love his red and black colors that match our UGA Bulldawgs.
Gooooo DAWGS ! Sic' Em Wouf Wouf Wouf