best way to gear motor to wheel

[michaelr123]

hello everybody that has accomplished the awesome task of mounting an engine to a bike! i for one, am struggling! just a bit! I'm wondering how people are engaging their engine to the wheel.

i'm ruling out friction drives cause they suck, but of course drivetrains and gearing and such become a difficult, expensive hassle.

one of my biggest needs is WHERE DO YOU BUY GEARS???? i've looked all over and only found a few spotty places that sell a few gears, can anyone offer a suggestion as to were i can find spur gears for a drive train?

the reason for all the trouble is because i know about gear ratios already (won't bug anyone with that) but i've devised a plan with a drive train that takes a chain input from my 60cc chainsaw engine that happens to be working now after alot of hard work, through a drive train (basically input 20 revolutions output 1 rev. 20:1 in that sense) and then bike chain sprocket that is on a shaft connected to the last gear on the drive train, which will run a standard 420 bike chain to the tire, and hopefully will be close to the magic 1:20 ratio im looking for.

anyone have any comments on this idea? how did you do it?? basically i just need a pic of your drivetrain and the websites where you got your gears from, other wise i'm good to go, as far as i can find so far gears are really hard to come by without like buying in bulk from a manufacturer,

 

[spad4me]

You bit off a huge chunk of the world.
Read this first.
http://motoredbikes.com/showthread.php?t=10392
A friction drive in a dry level climate is very easy to do.
Then there is belt drive like GEBE. Very nice!
Then a scooterguy setup. I use this type of setup now.
Link.
http://www.motoredbikes.com/showthread.php?t=17961


and finally a cheap place to buy sprockets and chains.
Be careful with the sizes.

http://www.surpluscenter.com/powerTrans.asp?catname=powerTrans


Google for thats dax or sick bike parts for more ideas or just lurk here.

 

[michaelr123]

i looked at the second link and your using a chainsaw just like mine, and only using a 1:5 ratio? does that work without the pedaling start? and am i wrong with my 1:20 ratio that i got off the internet?

and by the way, i have a 420 chain on my mountain bike, what type of sprockets will fit this chain?

and one more thing, how did you attach a sprocket to your chainsaw engine clutch? it looks all too easy in your pictures

and one more thing, i saw belts for another idea to replace a chain drive, i can see how this would be alot easier but you still have to deal with the gear ratios and such right?

 

[Stan4d]

Hi michaelr123! Perhaps you missed this:

New Members MUST POST HERE FIRST, so everyone can meet you. Tell us where you're at and what you ride. If you're new to MotoredBiking, or to Forums, this is a great place to let us know that, too.

Please reintroduce yourself. I will move the thread to a more appropriate forum.

 

[michaelr123]

How to attach a Sprocket to the motor

now that i have a better idea of how this is suppose to go, i'd like to know how people are going about getting a sprocket to run on the end of their chainsaw? are you just welding it to the bolt on the shaft? or a set screw kind of deal? and doesn't this by-pass the clutch of the chainsaw?? it's what it looks like you guys are doing, but i haven't found any forms at all that relate to this part of the build

 

[srdavo]

http://www.motoredbikes.com/showthread.php?t=25441

http://www.motoredbikes.com/showthread.php?t=4770

 

[michaelr123]

hey thanks, that first video is great, is its really that simple? all i have to do is attach the sprocket to the outside of the clutch however i can do that? cause i can have that welded, to that bolt like i was talking about,

 

[ferball]

I am in the middle of a weed whacker build and here are a few things that I might suggest. Sprockets off of old kid coaster brake bikes are easy to take off and easy to come by weld them to the appropriate size nut and attach to a shaft this has worked great for some of my chain drive projects I did with an in frame motor.

For my weed wacker project I am forgoing the clutch all together. The action of lowering or raising the spindle will give me all the "clutch" control that I think I will need. This is with a friction drive, but I am sure a similiar idea could be accomplished with an idler pulley type idea, similiar to the deck blades on a riding lawnmower.

 

[michaelr123]

hey quick question, why does the other post i made to this forum redirect me too this one? that one had some really good videos on it, any idea?

 

[Stan4d]

This is that post. Scroll up.