Wanted: Speedway TC drive and Driven clutch assemblies
- Thread starter ruppking
- Start date
I would just buy new. i can't remember if the original is 5/8" belt or not. If it is, and AjF gives you his driven, you probably won't find a 5/8" belt drive unit. Yes you can modify the current variety of new series20 Comets to use a 5/8" belt (instead of the standard 3/4" belt), but that requires a Lathe. just buy new Comet drive and driven series20, and a new Comet 203578 belt, you'll be better off.
https://www.vmcchineseparts.com/pro...5-8-bore-torque-converter-go-karts-mini-bikes
https://www.vmcchineseparts.com/pro...4-bore-for-go-karts-and-mini-bikes-version-70
https://www.vmcchineseparts.com/pro...5-8-bore-torque-converter-go-karts-mini-bikes
https://www.vmcchineseparts.com/pro...4-bore-for-go-karts-and-mini-bikes-version-70
When I was putting my blue angel together I needed the driver and the driven. I thought that to use a new 20 Series I would have to cut the base plate to fit the driven in. Since the bike was uncut and otherwise original I decided to find original stuff. I got the correct belt from an online supplier and it’s worked great.
you do NOT have to cut anything to put a new Comet series20 (or clone) in any 14" wheel Speedway. They were already designed for that system. It drops right in.
Now 1970-1972 Speedway 10" wheel bikes, that's a different story. Because they had a 5" driven. And to fit the Comet 6" driven, yes some minor cuts have to be made. But all the mid-1973 Speedway 10" wheel bikes are set up for 6" driven Comet units, they drop right in (they moved the jackshaft a bit towards the front of the bike.) This is when Speedway made the 10" and 14" models more similar, using the same kickstand (just shorter), same footpegs, same handlebars, same torque converter, same seat... they were trying to minimize inventory to save money.
The 14" wheel Speedways (Blue angel, Red baron, Green horn) ALL were designed for a 6" driven. And most of them got the Comet units too (some early 1972 had Fairbank Morse, but still 6" driven.) So the Comet (or clone) 6" driven and drive system drops right in, no modifications needed.
Using a 50 year old Torque converter is frankly, just silly, and probably expensive (if you can even find it.) It's the one thing that gets the crap beat out of it. Just put in a new Comet series20 (or clone.) You'll have better performance and you can get parts for it!
Now 1970-1972 Speedway 10" wheel bikes, that's a different story. Because they had a 5" driven. And to fit the Comet 6" driven, yes some minor cuts have to be made. But all the mid-1973 Speedway 10" wheel bikes are set up for 6" driven Comet units, they drop right in (they moved the jackshaft a bit towards the front of the bike.) This is when Speedway made the 10" and 14" models more similar, using the same kickstand (just shorter), same footpegs, same handlebars, same torque converter, same seat... they were trying to minimize inventory to save money.
The 14" wheel Speedways (Blue angel, Red baron, Green horn) ALL were designed for a 6" driven. And most of them got the Comet units too (some early 1972 had Fairbank Morse, but still 6" driven.) So the Comet (or clone) 6" driven and drive system drops right in, no modifications needed.
Using a 50 year old Torque converter is frankly, just silly, and probably expensive (if you can even find it.) It's the one thing that gets the crap beat out of it. Just put in a new Comet series20 (or clone.) You'll have better performance and you can get parts for it!
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I was under the impression that the 20 series comet driven was wider (diameter of the sheave wasn't the problem) and a section had to be cut out for the cam. I never tried to fit one so you know better than me, but if they do fit I'd be interested in converting because these original drivers wear out.
