Do we need a " belt driven" thread?

[Trey]

That is a lot of fednotes! Those colors look pretty good together.
I can't seem to find the sheer strength of the nubs on these belts. I wonder if someone could use nothing but this type on a build? They appear to transfer power dependably, from what little I've read. There would be a considerable amount of milling of new gears I'm guessing.

Street price depends on what street

 

[Trey]

Correction: The Gates website says their Gates Poly Chain GT Carbon matches the capacity of roller chain drives width for width in post pitch sizes.
If that is correct, that leaves alot of options.

 

[rustycase]

Yes, it's a lot of frn's for the likes of people like me, too...
Never-the-less, Many pedalers drop far more than that for their city bikes, and even more than that for their road bikes.

Yet we were only concerned with the drive system, right?

Just recently, Lord Vader made a post about the gear he cut on his lathe for another fellows lathe which had a bad component.
Probably not much more difficult to cut a round toothed sprocket.
...and there seem to be even more fellows, these days, with the cnc machinery!

Bottom line will be what Gates has to say about the rating of their belt.
They do make high quality products, have done all the research, and will happily present all the appropriate specs.

Best
rc

 

[silverbear]

As I mentioned I'm planning on putting together a belt driven cruiser using a 1951 Schwinn cantilever frame. I've been setting bits and pieces aside for this build, using things I have already on hand and trying to keep the costs down and the quality up... not always an easy thing to do.

I have two different engines in mind. One is the 5 horse Brigs & Stratton flathead, following the lead of msrfan. Love his Whizzer inspired builds. The other engine of choice is the 212cc Predator. The Brigs has lots of appeal on many levels... it is made in America and is part of our national history. Parts are easily available. It is a reliable motor with plenty of grunt for what I intend.

The Predator is going to cost me less money for a brand new engine ( a hundred bucks when they're on sale) and if the motor goes bad it is easy enough to replace. Upgrade parts are becoming more readily available. I put this same engine on a snow blower for my son this winter and it is easy to start, reliable, etc. Of course it is Chinese, but for the money is well made. It would also provide plenty of power for my needs.

I'm weighing things and mulling it all over so I have a plan before I begin. I like to look at other people's builds to get ideas and I've been trying to remember if there are any 212 Predator builds done by members here with a belt final drive. I can't think of any. Can someone point me to one? I'd like to study it if I can before deciding what engine to use. If your money was limited (real limited) which would you choose?

Components I already have are an in-frame copper gas tank Tinsmith and I made a couple of years ago. I have a nice set of vintage Schwinn rims for the wheels and Atom drum brake hubs set aside for it. The rear hub has the sprocket on the right hand side for the pedal chain... an oddball hub perfect for a belt driven sheave on the wheel. Front suspension fork is a Suzuki K-10 and I've already modified a headlight for the ears from a Harbor Freight dune buggy light. I'd like to go with extra wide fatty tires. Have a nice vintage seat I've already upholstered in elk hide. So, I'll use up some things I already have on hand and try to limit what I have to buy. It will be a nice ride, very much a light motorcycle with plenty of power, a nice throaty exhaust., good brakes, smooth ride and good looking without trying to look like anything in particular.

The big decision is what engine? And what are the real costs of the engine? The Briggs will be used and I'd rather not have to rebuild one. Where do I find it? What's it going to end up costing to rebuild it stock? The predator will need to have the governor removed and as I understand it that means a couple of parts inside need to be upgraded to handle the increased r.p.m.s...So what's the real cost of the engine? These are the things I need to research. If you can think of someone who has done the 212 as a belt drive I'd like to read the thread. Maybe I already have and just didn't pay attention. I will now! Thanks for any thoughts on this.
SB

 

[mason_man]

Hi silverbear, racie35 has one in the whizzer forum,it's Whizzer Ambassador HF engine install. 04-02-2013.
it's all belt drive.

Ray

 

[silverbear]

Ray,
That's a beautiful bike racie35 put together.
Did he also do a build thread?

What I'd most like to find is a cantilever framed build starting from scratch... engine mounting, what clutch, pulley sizes, belt clearance issues, etc. Things which would help guide me through a build. I'm being lazy. I want somebody else to figure out how to do it and then follow their lead.

 

[silverbear]

This is what I have in mind for the build I was talking about. What is pictured is a 53 Schwinn Hornet which ended up getting a 99cc Predator engine before it was sold.

What I want to build ( a 51 Schwinn Hornet) will have the same headlight and forks and the same gas tank, but in copper. Wheels will be different in having Atom drum brakes with 11 gauge spokes laced into 50's Schwinn rims and fatter tires if I can get away with it... I think there will be room for a set of Fat Franks. The tires along with the fork give a great, smooth ride.

The frame leaves plenty of room for either the Briggs or the Predator. It is a strong frame, made in Chicago. I'm going to like this bike. Any opinions on the engine?
SB

 

[racie35]

Hi silverbear---i did kinda take pics and such of what I did to the ambassador but it wasn't a lot really...mainly made a mount to roll the engine 90degrees so it would fit the TAV at the correct distance and even...that's actually in the original jackshaft mount...I just made a shaft ---so the tav has a 2.3" pulley off the back driving the original belt sheave etc----works very well,has lots of pull. Currently has a whizzer 22mm carb but I'm gonna try a 26 because I have one

 

[silverbear]

racie35,
That's a fine looking Whizzer you have. I'm assuming that you removed the governor on the Predator engine. Did you change any of the internal components? What would you guess you're revving it up to?
SB

 

[racie35]

The engine as used won't require any internal mods...only reason I removed the gov was to seal the shaft hole,otherwise I would left it in. Lotta people are buying parts anticipating higher rpms I guess,and that's okay if it gives em peace of mind. So, as used here on this one--no mods needed

 

[silverbear]

That's good to know. I have no interest in finding out how fast the intended build will go. It will go faster than I want to go; faster than I would have any business going on a modified bicycle. Part of the idea in having a beefy engine is so that I don't have to wind it out in order to climb a hill.

Excuse my ignorance, but what is the TAV? That must be the clutch I would guess. I'm not that familiar with Whizzer components. Primary drive is belt to some kind of automatic clutch/jackshaft and secondary belt is to the rear sheave. Is that right?
SB

 

[racie35]

TAV is a torque a verter (I think that's the term)...you can get one from BMI and sometimes cheaper on ebay.....they're similar to a Cvt except when the engine returns to low speed they open up enough to just sit there idling... .they really work good.....you won't be pushing up any hills or pedaling to get going...don't worry

 

[silverbear]

Do I have this right? The TAV bolts onto the engine directly and the engine drive shaft fits into the Comet clutch which connects by belt to a kind of jack shaft which normally has a sprocket on the inboard side for either 41 or 35 chain. Instead of the sprocket you have a pulley which connects a long belt to the sheave mounted to the rear wheel. Is that it?
SB

 

[silverbear]

Like this?

http://www.ebay.com/itm/GO-KART-TOR...049?pt=LH_DefaultDomain_0&hash=item4d06709041

But changing the sprocket to a belt pulley.

If this works then it is certainly a reasonable price. I'm guessing that the shaft the secondary pulley rides on would not be long enough to both mount the pulley to the rear wheel and have room for lateral adjustment to get it centered. Did you have to change yours?
SB

 

[racie35]

Messaged you silver

 

[silverbear]

I found a number of pictures of your engine install on this thread...

http://motorbicycling.com/showthread.php?t=45178

Nice.
SB

 

[racie35]

Yes...and if you look on the images you'll see where the jackshaft plate was only used to get the measurements right...then we used the existing jackshaft mount

 

[silverbear]

I did some asking on another thread if the 212 Predator will fit in a cantilever Schwinn frame...
http://motorbicycling.com/showthread.php?t=47503

...and it is pretty clear that it won't. Having given it some long thought I have decided to use another motor I have on hand which I know will fit in the frame and has nice power. It is a 1970's Jacobson 2 stroke of 147cc's made in Wisconsin. I'm trying to keep costs down on this build so am looking around at what I have to see what can be utilized. I still want to go with a belt driven sheave on the rear wheel. I have a rim from a 24" skinny tire bike which I think may work nicely. See photos.

Having looked at photos of motorcycles from the glory days just after 1900 I see some variation in sheave diameter. Is there a most desired diameter? What is the size of the Whizzer sheave? Any suggestions are appreciated.First photo shows sheave lying on a 26" wheel. Second photo shows sheave next to the rim it will attach to once the wheel is built.
SB

 

[silverbear]

In looking again at other sheaves in the links on this thread to other builds, the 24" wheel as a sheave is too big. I looked around in the department of dead donors and found a 20" wheel in good condition. Steel with nice chrome yet, even. It only took a few minutes to remove the tire & tube and then cut off the spokes with the dremel rotary tool with a cutoff wheel.

It is pictured lying on top of a 26" wheel and looks more the size of what others are using... in the ball park anyway. The tire size for that rim is 20", but the actual rim measures a bit over 16" in diameter.
SB

 

[racie35]

A whizzer sheave is 15"....not sure what belts you'll run to the front....most of these are AX belts of varying lengths,depending on frame length and pulley size used up front.....so to me mounting a rim to spokes would be easy enough but leave that dilemma. That said I think most wouldn't mind a little bigger rear sheave opening up different gearing options.