List of motorized bicycle gearboxes

GoldenMotor.com

rustycase

Gutter Rider
May 26, 2011
2,746
5
0
Left coast
I like Gareth's ra drive!
What gear set did you use as a base for your project?
...something that might be available here???
Best
rc
 

MotorbikeMike

Dealer
Dec 29, 2007
477
3
18
Sacramento
Hi mezzenger, I am not in tune with everything being made, BUT I do know that EZMotorbike makes the Q-matic, and the Pacesetter drives especially to fit HauSheng and Honda GX50H 5/8 keyed shaft engines, also the internal clutch model of the Hau Sheng (with special adapter we make).

The Pacesetter is also available drilled to bolt right on to the Harbor Freight 79cc Greyhound, and the 99cc predator models.

It is adaptable to many other engines, but these are the patterns I am currently aware of. I am currently interested in mounting one to a 3.5 HP Briggs and Stratton Vertical tho I am not sure how I will bolt on to the old engines that I currently have.

I hope this helps answer your question.

Mike
 

CycleRyder

New Member
Jun 23, 2017
28
0
1
34
I'm kinda new to the 4 stroke relm of MBs but I had a 4G fail on me twice inside of the first month of use. Now I'm looking at getting a CVT pocket bike transmission. Been eyeing a few that are surprisingly much cheaper than the Grubee 4G or the older Bikeberry 5G single chain & the clutch drum & bolt pattern looks like it would fit my HS 142F. Can anyone let me know what pocket bike CVT transmissions can fit my 4 stroke motor? I'll attempt to post the measurements of one CVT I was looking at getting.
 

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MotorBikeFab

New Member
Sep 5, 2018
29
18
3
80
SoCal
MotorBikeFab.com
Because I am new here I can't post links...

What do people think about the Piston Bikes "79cc Transmission for Predator 4 Stroke"
If you do a Google search for "79cc Transmission for Predator 4 Stroke" - a number of links show up and about 4 down is the one for PistonBikes. Comes with a MaxTorque clutch for $100.

What do people think about the Max-Torque clutches? Can the Max-Torque clutch be "tuned".

Thanks so much.
 

MotorBicycleRacing

Well-Known Member
Jul 28, 2010
5,844
109
63
SoCal Baby!!!
www.facebook.com
Because I am new here I can't post links...

What do people think about the Piston Bikes "79cc Transmission for Predator 4 Stroke"
If you do a Google search for "79cc Transmission for Predator 4 Stroke" - a number of links show up and about 4 down is the one for PistonBikes. Comes with a MaxTorque clutch for $100.

What do people think about the Max-Torque clutches? Can the Max-Torque clutch be "tuned".

Thanks so much.
That clutch looks like a MaxTorque clutch but does not have MaxTorque stamped on it.
 

Tony01

Well-Known Member
Nov 28, 2012
1,729
1,721
113
sf bay area
Because I am new here I can't post links...

What do people think about the Piston Bikes "79cc Transmission for Predator 4 Stroke"
If you do a Google search for "79cc Transmission for Predator 4 Stroke" - a number of links show up and about 4 down is the one for PistonBikes. Comes with a MaxTorque clutch for $100.

What do people think about the Max-Torque clutches? Can the Max-Torque clutch be "tuned".

Thanks so much.
that clutch is not a max torque. and it doesn't say anywhere that it comes with an MT. MTs have internal keyways. this clutch has an internal key. One that I got (clutch only) was actually 16mm, not 5/8". Extra .005" on the diameter can destroy your crankshaft eventually. you never know with junk.

MTs are great clutches when used on engines at or under their rated power of 8hp. They can be tuned. If you run low gearing of around 12 to 10.5 you can just run the clutch stock, if you go tall like 10 to 8:1 I suggest replacing the stock silver spring with a green spring.

That plate might still be a good deal though. make sure you get a MT clutch with the right sprocket size for the chain for that plate, probably #35 but check first.