Weed Eater Friction Drive Bicycle

[BentTooner]

Hi,

I'm not sure about the 'new posts' issue. Maybe that feature means "new to you" in that these would be posts you haven't looked at yet. Since you and I seem to be the only ones posting on this thread, if we get an email notice of a new post, we go to this thread from our email client and read the other guy's post.

At that point, it's not "new" any longer (to us) so it won't show up as "new" posts to us. Maybe other people would see it as "new."

We are VERY lucky to have all the **** we have in the US. I bought several of those small engines on ebay at the time. I still have 1 or 2 of the 4 stroke engines in my shop and 2 or 3 of the 2 stroke engines. Sometimes, you see them on Craigslist attached to a weed eater...

 

[landuse]

You will not get a decent motor here for less than $100. And that is a lot of money here. People seem to hold onto the stuff they have here. Nobody throws stuff away. If they do it is totally beyond repair. There arent any engines for sale either. You have got to buy the whole weedeater. These are typical ads you will see for weedeaters/brushcutter.

http://durban.gumtree.co.za/c-Stuff...sale-Brushcutter-Weedeater-W0QQAdIdZ329772736

http://durban.gumtree.co.za/c-Stuff...sale-Brushcutter-Weedeater-W0QQAdIdZ329772736

Not cheap. I have a chinese 43cc brushcutter as well, but I am hesitating to use it on my bike because I still want to use it as a brushcutter as well

 

[BentTooner]

The engines I bought in 2008 were all about $30 - $50 PLUS shipping which was about $20, usually. So, the total for ebay engines was about $50 - 80 USD.

Maybe we should start a business? I buy the used engines here on the cheap and ship them in bulk to you and you sell them there...

 

[rawly old]

Landuse,
Since you're building a channel drive you might want to look at the one
made by thatsdax.com. simply because his is drilled in such a way as to
give the most options for type of bike and configuration.

 

[landuse]

Landuse,
Since you're building a channel drive you might want to look at the one
made by thatsdax.com. simply because his is drilled in such a way as to
give the most options for type of bike and configuration.

Thanks Rawly old, I will look into that.

 

[rawly old]

It rains here a lot. I finally got frustrated with slipping drive rollers.
so here's what i did with one of my old friction kits, 50% faster on any
day regardless the weather.

 

[landuse]

It rains here a lot. I finally got frustrated with slipping drive rollers.
so here's what i did with one of my old friction kits, 50% faster on any
day regardless the weather.

Nice. What is the metal rim in your spokes made of, the one the belt runs on.. How do you 'fix' it in there. If I look at your pics, the belt is not 100% lined up with the drive rim, but sort of at an angle to clear the tyre. Is this correct?

 

[rawly old]

It is the aluminum rim from a 20" kid's bike. The inside of the rim is 15.5" in dia.
center it over a regular 26" wheel and mark where the spokes meet. I then used
a circular saw to cut notches 3/8" deep to receive the spokes.(notch width 1/8")
I then ran tie wire behind the spokes next to the rim to hold it in place. this works
since all the stress is against the notches.
The angle you'll have to work out once the rim is mocked up in place since frame
geometry varies widely from bike to bike. On mine the belt goes behind the brake
caliper with 3/16" clearance on either side between caliper & tire. If you attempt
this you should really use a 35cc or more though a lot of Belt drives do use 25cc
with a very small cogged pulley and belt (see Golden Eagle Bike Engines; their kit
would be mighty pricey shipped to S.A., but their site is worth looking at for ideas.)

 

[rawly old]

I should mention that this belt setup isn't as simple as it appears. a
suitable shaft is something that will likely take special tooling. Not
having a lathe, I brought mine down to size for the clutch drum turning
it in my hand while stroking with a file, pretty labor intensive on case-
hardened steel.
If you're in a rural area there shoud be a fair selection of pulleys laying
about from derelict farm equipment. Too large and you lose low end
power, too small and you may as well stay with friction drive. The one
shone is about 1" made from 2 belleville washers with a spacer between.
It gives me a 17.7 to 1 ratio and is just about ideal for my 35cc honda
4 stroke. The outside pulley which is interchangeable is 1.25" for flat
terrain. The 1" will do 32/33mph wide open @8000 rpm, but cruises at
half that. Potentially, the 1.25" might do 40, it's meant to mush along at
22mph @4200 rpm. At that speed I can pedal support in high gear at a
comfortable cadence without a great deal of effort and get about 180 mpg.
( that's U.S. gallon)

 

[landuse]

OK, I see how you did it now. I thought it was some sort of kit that you used. I like the idea of the washers and spacer. Real DIY. Thats what I love.

I am probably going to get a 30cc Ryobi from someone here at work today. He says it is practically brand new, so I will see what it is like and think up some use for it as well.