Run in Reverse?

FatLazyAndStupid · #1 10-22-2008, 07:59 PM

I have some ideas about putting a motor on a bike. I want to mount a 49cc 2cycle engine to the frame with the drive shaft on the right side of a bike with 2 sprockets in the front and 3 or 4 in the back. With the setup I'm thinking of I could change what gear I'm in and theoretically achieve greater speeds or lots of torque depending on the gear. The engine would connect to the larger of the front sprockets and the smaller front sprocket would be connected to the back sprockets. I would have a pull, kick or electric start with the pedals removed. With a chainsaw style clutch so I can start it in place then go. All of the kits and motors I have seen are made to drive an additional sprocket added to the left side of the rear wheel. I have seen some Chinese kits that look pretty good and I would need most of the parts from the kit to make it work, but there is one main question that is keeping me from starting: Is it possible to run a 2cycle engine backwards or am I out of luck?

hill climber · #2 10-22-2008, 09:23 PM

yes you can run it backwards just have to time it

FatLazyAndStupid · #3 10-22-2008, 09:32 PM

Thank you now I know its at lest possible to do, I suppose I will figure out how to set the timing whenever I purchase it.

Which would be best for a motored bike disk or rim brakes?

jerseykat1 · #4 10-23-2008, 10:53 AM

Quote:

Originally Posted by FatLazyAndStupid

Thank you now I know its at lest possible to do, I suppose I will figure out how to set the timing whenever I purchase it.

Which would be best for a motored bike disk or rim brakes?

if you click the link a the top left that says "looking for performance" in red you will see a kit that allows you to properly mount the motor, and use your bikes rear gears to shift. It is called a shifting kit. I have one installed on my bike, and it makes the ride so much smoother, not to mention you can change gears.

disc is best if you don't get the cheapest ones you can find. But V brakes are best on a budget, provided your frame has the attachments on it for v brakes. unless you ride in wet or humid conditions i would just go with v brakes and a good set of pads.

NEAT TIMES · #5 10-23-2008, 01:32 PM

LAZY , JUST KIDDING. WELCOME TO THE FORUM . YOU WILL LIKE IT HERE. I THINK "SICK BIKE PARTS" HAS ADD IN LEFT COLOMN. SEE THEIR WEB SITE AND VIDEO`S THEY HAVE A NICE SHIFT KIT. I BOUGHT ONE , HAVE NOT INSTALLED IT YET. I THINK THE PRICE IS GREAT WITH THE QUALITY OF THE PARTS. HOPE THIS HELPS. MANY ON THE FORUM LIKE THEIRS. RON

FatLazyAndStupid · #6 10-23-2008, 11:14 PM

Would a chain saw run in the correct direction if mounted almost upside down?
How difficult would it be to attach a sprocket to a chain saw?

jerseykat1 · #7 10-24-2008, 07:51 AM

chainsaws will likely have a sproket already mounted. No it won't be too difficult just have to relocate the carburator so that it is not upside down.

welcome, and did you read any of our responses?

FatLazyAndStupid · #8 10-25-2008, 01:25 PM

Quote:

Originally Posted by jerseykat1

chainsaws will likely have a sproket already mounted. No it won't be too difficult just have to relocate the carburator so that it is not upside down.

Chainsaws don't come with sprockets but this is the best picture I could find of what a chainsaw does have. Here is a picture of the chain that chainsaws have, the chains on chainsaws work differently than bike chains do and that is why I asked about connecting a regular sprocket.

Quote:

Originally Posted by jerseykat1

welcome, and did you read any of our responses?

The shifter kit is too expensive and I'm just trying to figure out a cheap and easy way to motorize a bicycle and make it go fast. I don't have much money to throw around and buy all the odds and ends that will fit together like a hand and glove so I have to make things work. I just figured a chainsaw with a sprocket attached would be the easiest way to make it work.

rrraul · #9 10-30-2008, 11:52 AM

Hey. I love the idea of timing the engine to run backwards. The shift kits are cool but it means that you have three chains on your bike. I think it would be much more efficient to have fewer chains and fewer moving parts. Another solution would be to put all the gears on the left side of the bicycle. But I haven't found any parts like that so I like your idea the best.

hill climber · #10 10-30-2008, 05:07 PM

with the ht motor your going to have to find a cassette with some pretty big gears or you will have no bottom end.