You're gonna like this

GoldenMotor.com

Wickedest1

Member
Oct 31, 2012
688
7
18
41
connecticut
Well, here goes another attempt to tempt fate.

I scored a wicked 2 stroke brush cutter, with a very hearty lil centrifugal clutch. The bar was designed to destroy 1.5" branches. Had a crappy carb that was discontinued way back in the 60s. No wonder they threw it in the garbage. Lo and behold, the 32mm intake for the nt carb bolts perfectly up to the carb spacer. Boom nt added. Was a little blubbery, but after ten thousand pulls, she fired up. 68 jet and she was dead nuts.

I had a giant bucket of jackshaft sprockets for#41 chain, some bastahd swiped it. But dumped a couple out in the process of jumping over the wall to my section. Anyways, after some of the o.g. s schooled me, i decided to go belt drive, as that would allow for rapid gearing changes to dial it in, much quicker than cutting chain and changing 45 dollar sprockets.

So, i cut the hub out of a 16" wheel and am mating the hoop to a 20" wheel. I was struggling with ideas and had initially come up with the idea to use threaded rod couplers with a slit notched into one side where i would fashion it to the sheave with rounded headed bolts. And, i was finalized on this in my head as my game plan. I pulled the rear wheel off my frame choice (old ross polo) i pulled the sprocket from the adapter and to my luck, a couple wrenches lined up on my bench, under the spokes and showed me the way.

I've discussed and researched gearing with a lot of people, and have a tentative final gearing setup. With a secondary back up plan (it's a secret 2 speed pulley ready for a jackshaft gear reduction).

The specs as my brain remembers

Bike choice is an older Ross polo banana seat bike with extremely horrible ebay springers up front. Ghetto rigged under sprung banana seat. Book rack from an old pedal build. The mighty little wonder power products, 2 stroke 35cc, heavy duty double wall aluminum 20" rims with 12g spokes sitting in a spoke recess. Kenda bricks. Will have real tall apes. And i have the original forks from the polo bike. Gonna run a 58" notched v belt on my homemade sheave.

I swear there is more, but I'm cloud connected right now and rambling. Check the pics i uploaded here:





 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
I bet you could stitch the 16" rim to the spokes with .032 safety wire. The holes should line up? 36 stitches should be plenty strong, heck 18 might do not, talking mega HP here.

Looks to me like the 16' rim may try to "wind" up the 3 braces with only one bolt each at the hub adapter.
 

Wickedest1

Member
Oct 31, 2012
688
7
18
41
connecticut
I bet you could stitch the 16" rim to the spokes with .032 safety wire. The holes should line up? 36 stitches should be plenty strong, heck 18 might do not, talking mega HP here.

Looks to me like the 16' rim may try to "wind" up the 3 braces with only one bolt each at the hub adapter.
You're absolutely correct. There will be bracing crosswise between each, kinda like bridge trusses. I mean this motor is maybe 1.5 hp at peak. Not looking to speed away. I may very well also attach the sheave with a few well placed bolts and flanged nuts with a groove in them.
 

Wickedest1

Member
Oct 31, 2012
688
7
18
41
connecticut
Well, i got more done on my belt drive. Motor plate drilled and tacked in place. Forward engine cradle/second mount fabbed and tacked in place. Seatpost adapter adapter(gotta look).

I went to my local lawnmower repair place looking for pulleys and belts. Man did i get the run around. They didn't want to help me for fear of liability. Literally would not sell me pulleys or belts. But that's ok. At the same time i was there another guy mentioned there was an electric motor company that specialized in pulleys and belts.

The electric motor place was frikin ecstatic to help me. Once i showed the owner the picture of my build, he offered me 25% off anything i ever will need to make a motorized bicycle. I purchased the smallest pulley available which is .80" for under 5 bux. Traver IDC is the company in Waterbury ct. Super cool people.

After installing the pulley, i measured twice for my belt. 56" is gonna be just right with a 2" idler. I'm stoked.

I will be working on my sheave spokes, hopefully this evening.
Thanks for looking





 

Wickedest1

Member
Oct 31, 2012
688
7
18
41
connecticut
I feel as if i should have gotten more done, but this was seriously time consuming without a full shop of tools. I got my spokes rough cut, they will need a little more filing to fit the curve of the inner circumference of the sheave. Got my central mounting point. Kinda copying a 3 piece rim for a car in a sense. The sheave supports will not bolt onto the center ring, but will be welded in place at both contact points. Thus making the sheave removable. I feel the center ring combined with short thick spokes and the small motor will be fine structurally. If not, more is less.

Oh and i salvaged the spokes from an old steering wheel





 

Wickedest1

Member
Oct 31, 2012
688
7
18
41
connecticut
Got the sheave welded up and in place. Had to make a small modification to the rack for the belt to clear. Fighting with shaft carrier options currently. But I'll figure something out.



 

Wickedest1

Member
Oct 31, 2012
688
7
18
41
connecticut
Got the shaft carrier sorted in the simplest fashion i could drum up after hours of trial and error. Simple shaft collar and a brace.