NMCruiser
New Member
My latest MB project was adding my Grubee 4-stroke kit to a Cadillac Fleetwood bike that comes with a Nuvinci hub. I fabricated a jackshaft to bring the chain to the right side of the hub. Most of the parts for the build were purchased from Staton.
Some photos of the MB
Here are the parts I used for the hub:
27-tooth sprocket for drive chain on hub
16-tooth freewheel for pedal chain
Washer to space between the 2 sprockets on hub
Torsion bars to keep hub from twisting in drop outs
Here are the jackshaft parts:
9-tooth keyed 410H sprocket
18-tooth keyed 410H sprocket
5/8 inch full key way shaft (6 inches)
5/8 inch shaft collar (qty:2)
3/16 x 3/16 x 1/2 key (qty:2)
2-bolt 5/8 flanged bearing (qty:2)
Here are the miscellaneous parts:
1-1/4 inch stainless steel saddle clamps (qty:2, note that I had to order 3 to make minimum order amount)
Drive chains (qty:2)
Throttle grip to replace Grubee dual brake controller and throttle
4 inch x 1/8 inch square steel tubing (6 inch length)
I also had to order the 2 piece Nuvinci hub dissembly/reassembly tools from a local bicycle store. Contact Fallbrook Industries (Nuvinci manufacturer) customer service to obtain a Nuvinci Owner's and Dealers Manual or obtain online. The Dealers Manual has the part numbers for the tools, but only listed one of the tool's part numbers. You will need both tools, which in my case were packaged together. Fallbrook can also tell you the tool wholesaler. I paid approx. $80 for the tools. The tools allow the installation of the sprockets on the Nuvinci hub.
After I drilled the holes in the square tubing for the jackshaft, bearing bolts, and u-bolt clamp bolts I cut one side off of the square tubing to make it a u-bracket. I also bought some stainless bolts and square aluminum tubing to secure the flanged bearing and to keep the u-bracket from spreading or collapsing.
I used a soldering iron to remove the sleeve from the throttle cable in order to attach the Grubee throttle cable to the new throttle grip. Be careful not to cut it too short. I cut a little at a time and experimented. Once I had the right length, I soldered the collar back on the end of the cable and reattached it to the Huasheng carburetor.
The bike will go 26 miles per hour on the flats, but the gear ratio is not quite low enough. I am able to climb a pretty steep hill at 15-16 miles per hour without pedaling. I weigh 265 pounds. The engine is not running in its power band at the highest 'gear' of the hub, so I plan on lowering the gear ratio to give better performance and possibly speed (given my weight).
If your Grubee gearbox did not come with lock and flat washers, try to get them from Bicycle-Engines.com or a home supply store and use Locktite as the gearbox mounting bolts can come loose and cause the clutch drum gears to strip. This happened to me and I had to order replacement parts from Bicycle-Engines.com. Give Jeremy a call at Bicycle-Engines.com. He is very helpful.
Some photos of the MB
Here are the parts I used for the hub:
27-tooth sprocket for drive chain on hub
16-tooth freewheel for pedal chain
Washer to space between the 2 sprockets on hub
Torsion bars to keep hub from twisting in drop outs
Here are the jackshaft parts:
9-tooth keyed 410H sprocket
18-tooth keyed 410H sprocket
5/8 inch full key way shaft (6 inches)
5/8 inch shaft collar (qty:2)
3/16 x 3/16 x 1/2 key (qty:2)
2-bolt 5/8 flanged bearing (qty:2)
Here are the miscellaneous parts:
1-1/4 inch stainless steel saddle clamps (qty:2, note that I had to order 3 to make minimum order amount)
Drive chains (qty:2)
Throttle grip to replace Grubee dual brake controller and throttle
4 inch x 1/8 inch square steel tubing (6 inch length)
I also had to order the 2 piece Nuvinci hub dissembly/reassembly tools from a local bicycle store. Contact Fallbrook Industries (Nuvinci manufacturer) customer service to obtain a Nuvinci Owner's and Dealers Manual or obtain online. The Dealers Manual has the part numbers for the tools, but only listed one of the tool's part numbers. You will need both tools, which in my case were packaged together. Fallbrook can also tell you the tool wholesaler. I paid approx. $80 for the tools. The tools allow the installation of the sprockets on the Nuvinci hub.
After I drilled the holes in the square tubing for the jackshaft, bearing bolts, and u-bolt clamp bolts I cut one side off of the square tubing to make it a u-bracket. I also bought some stainless bolts and square aluminum tubing to secure the flanged bearing and to keep the u-bracket from spreading or collapsing.
I used a soldering iron to remove the sleeve from the throttle cable in order to attach the Grubee throttle cable to the new throttle grip. Be careful not to cut it too short. I cut a little at a time and experimented. Once I had the right length, I soldered the collar back on the end of the cable and reattached it to the Huasheng carburetor.
The bike will go 26 miles per hour on the flats, but the gear ratio is not quite low enough. I am able to climb a pretty steep hill at 15-16 miles per hour without pedaling. I weigh 265 pounds. The engine is not running in its power band at the highest 'gear' of the hub, so I plan on lowering the gear ratio to give better performance and possibly speed (given my weight).
If your Grubee gearbox did not come with lock and flat washers, try to get them from Bicycle-Engines.com or a home supply store and use Locktite as the gearbox mounting bolts can come loose and cause the clutch drum gears to strip. This happened to me and I had to order replacement parts from Bicycle-Engines.com. Give Jeremy a call at Bicycle-Engines.com. He is very helpful.
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