Rear belt drive?

[wayne z]

ragjoint ruins spokes, belt sleeves have torque but theyre on the weakest point on the spokes ........ a hub clamp would be the best option but for a belt it might need to be more heavy duty

Please explain why the hub clamp, or anything ,would have to be more heavy duty with a belt instead of a chain.
The belt slips a little with each power stroke of the engine, and relieves some of the torsional stress spikes to the whole drive train.

Wizzer has been using spoke mounted sheaves with good results for a very long time.

I've never heard of a rag joint , properly installed, ruining any spokes on a wheel that has tight spokes to start with. I've built 6 bikes with rag joints so far. Only prob I have with them is the trouble of installing themLOL

 

[Fulltimer]

Spokes have been destroyed and the reason probably is because of what you said. To eliminate that possibility go with a hub adapter. I think what we are attempting to do in this thread is to come up with a system that is pretty much fool proof.

1. Belt drive right from the motor.
2. A drive belt that is cheap and readily available.
3. A rear belt pulley attached to the hub.

This type of setup is about as simple as you can get. About the only thing that would ever need to be replaced is the belt. There would need to be something to adjust the tightness of the belt to compensate for wear and/or stretching. But that should be all and the belt should last darned near for ever.

Terry

 

[Dan]

Remember Guys, we are the "B" team! (snork, for Belt. yes, thats it, belt) The free world is depending on us! Mostly for the laughs but hey.

I have the parts to try a rag joint first. Just between us? Kinda disgusted with some, some of the folks who make or sell the adapters and don't really want to buy any thing from any one with some of the silly stuff some folks are doing or trying to dissuade us from other suppliers.

So I volunteer to do the rag-joint for now. But looking forward to seeing what else is done!

I was thinking further reduction was needed. Will do the math when I get closer but have a 4G and a Honda 50cc. Is a compromise but thinking the timing belt has the immediate "umph" with the rear belt being a regular belt to absorb some of the shock load?

I would really like to try a CVT tranny down the road but will only confuse me as I lack focus so badly!

If it was engine+st8 to rear wheel, thinking the sheave would have to be as big as the wheel.


Hope I didn't go off the communal path here. Is just the parts I have on hand and hatred for marketing folks turning my hobby in to an unpleasant.


In any event, Gentlemen/woman, start your thunking!

 

[Fulltimer]

There isn't anything that says a rag joint can't be tried. It would be cheaper.

Terry

 

[Dan]

Could some one double check my math?

drive shaft size, 1.75" X 6.5

To 1.25" X 6"

Giving a drive ratio of 17.83:1. At 7,500 RPM, a speed of 32.5 MPH.

Or with a 5" wheel ring, 14.86:1 and speed of 39 MPH. I have yet to look and find out if a 5" sheave can be found?


Really is fun-ner to be able to ask and not end up at the end go "oh sheet! dang math" lol

 

[Dan]

For giggles, I tried 2.5 X 40" drive ring.

is 16:1 with a top end speed of 36MPH! That would be perfect!

Dunno here and have not thought it out but there would be an alignment issue but man that is perfect and less parts! Cheaper and more reliable. Thoughts?


I really like how that would look. One belt and uber shade tree engineering looking

 

[Fulltimer]

I think 35 or 36mph would be about right. I assume that the low end would still be okay.

Terry

 

[Dan]

Used to be folks aimed for 18 to one but see more and more folks going for around 12 to one or so. My HF daily rider is about that, (lil over 12 to one) is not blazing quick off the line but more then acceptable.

Would still have to be jack-shafted over so lots of room for other ratios. Votes? Would be cheaper then using a 4G.....

Or could stick with putting a belt pulley on the 4G. Do they sell 15mm sheaves? Not a big deal, could just drill it out but be kool to have plans that could be used with off the shelf parts for folks with out a drill press.

LOL, again with my lack of focus. Can never stick to a plan. But is just part of the fun I guess.

 

[rohmell]

My next project is going to be a 20" bicycle rim as a sheave and this belt:
Vibration Free Link Belt
The beauty of the belt is that by installing and removing the links, it can fit any diameter pulley.

 

[Dan]

My next project is going to be a 20" bicycle rim as a sheave and this belt:
Vibration Free Link Belt
The beauty of the belt is that by installing and removing the links, it can fit any diameter pulley.

Was looking at those Rohmell. Really like the concept. Please post how it does. Really curious.


Wow, just read the reviews on it. 5 out of five gave it 5 stars!

 

[bairdco]

i just found this thread.

i've been putting this idea off for 2 years, but i know exactly how to do it, and it would run almost the exact ratio as a chain driven bike. i've also solved the problem of having a belt wider than the chain fit inside the clutch cover on the china motor.

unfortunately, i don't wanna give any other details at all, 'cause if it works, i hope to market it.

but you guys are on the right track, and there's nothing i can do if you beat me to it. that's what it's all about, right?

 

[Fulltimer]

I think a narrow belt would work inside the cover.

Terry

 

[GEJoe]

I too have pondered the belt drive issue, having had 3 torn up belts and 3 spoke breaking episodes with my Golden Eagle setup. I even discussed the problem with Dennis at golden eagle several years ago, suggesting that it might work better if the drive ring could be made to engage more than half the spokes as it does now. Even some older bike engine setups I have seen use a drive ring fastened to the rim rather than sending the drive force through the spokes, like the Whizzer setup mentioned earlier. Leaving the spokes out of the drive train seems optimal to me. Last summer I converted to 12 gauge spokes and now have a Dax setup that is not running yet. I don't like the rag joint and will be ordering the manic mechanic hub soon, as it too uses all the spokes instead of half of them.

 

[rohmell]

I have a GEBE setup, and don't like the way the drive ring is set up.
I am building a new setup. I am planning on using a 20 inch bicycle rim and welding it to the main rim with flat stock, kinda like this:

Egads, that's a small pic, here's something larger:

 

[GEJoe]

I have drilled tiny holes in my plastic drive ring opposite the spokes it snaps to and put zip ties through to the other spokes. I believe that is why I rode for 3 years before breaking spokes. Before that they broke in only a few months.

 

[Ruby478]

has anyone made any progress ?

 

[GEJoe]

Does anyone know if the whizzer drive ring attaches only to the spokes on one side of the wheel like gebe or uses all of the spokes? I just bought the manic mechanic hub to use with my chain drive and it seems to me that a belt drive ring could be bolted to it just like a sprocket is. Of course, the belt drive ring is much larger diameter. What think?

 

[rustycase]

I'd like to run a rear belt to lose the chain...

Is anyone going to try the cog belt like on the new TREK bicycle?
I think it will be too pricey for the likes of me... :-(
rc



...if they will hold up to an athlete pumping at all his strength, I think they should work for the more distributed application of torque from a motor???

 

[lowracer]

I've got 2 MB's that are V-Belt drive. My method is to mount another same-sized rim to the spoked rim. I clean both surfaces up with a file & some rubbing alcohol, then JB Weld together, then drill small holes through both (not thru the tube channel & bolt together w/ a few thin bolts with nylock nuts. They haven't needed truing with thousands of miles on them. The extra rim (pulley) strengthens the spoked wheel. I run powerful, fast engines (Lifan 2.5 hp 98cc & Stage 2 Pocket bike engines) & the setup seems to handle the loads just fine so far...
-Lowracer-

 

[Texhun]

Gasbike.net has belt drive kits maybe you can take a few mounting techniques from there they have pictures of it.