Idea for converting ISO 6 bolt to Freewheel

lowracer

New Member
Got an idea for a solid mount, wobble free, freewheel drive.
I have a Shimano threaded rear hub that isn't being used for anything & a spare Sun Rhyno lite front wheel w/iso 6 bolt mount & 20mm thru axle.
I measured everything & this will work. I was thinking about cutting the end off of the freewheel hub leaving just the threaded section and spoke attachment flange. The outside diameter of the spoke flange is 54mm and the bolt holes of an ISO 6 bolt hub is 44mm. I'm showing a disc rotor in the pics just to get the holes figured out for bolting to the iso hub on the spoked wheel. Everything lines up including the spoke holes. Those can be used as a pilot hole to drill the 6 larger holes to mount the flange to the wheelhub. The front wheel can then be installed in the fork dropouts backwards (6 bolt to the right). Mount the cutoff flange, thread on an ACS Crossfire flanged freewheel & mount a sprocket (Sick Bike Parts sells them). Just gotta run v-brakes instead of disc since using the disc mount for the freewheel drive.
Too bad they dont make double sided 6 bolt hubs.
See pics
-Lowracer-
 

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Ok,
I just cut the hub and filed it flat & smooth. Here are a few pics of where this idea is going. There wont be a rotor involved, just showing pics of it since its the same bolt pattern as the wheel I'm going to mount this to.
I have 2 front wheels laying around both have ISO 6 bolt disc hubs. One is 110mm wide & the other is 100mm (std). I'll check to see if there is enough clearance on the std wheel too since that would be more common & an easy way to make a motorized chain drivetrain w/freewheel able to pedal totally independent of the motorized drivetrain.
-Low-
 

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KC,
I am solely a 2-stroker at the moment. I have 3 Tanaka's (32cc, 47cc & 47r) & 2 Mitsubishi's (43cc's) in the stable. I'll probably be looking to sell the Mitsubishi's soon (both have only a couple hours on them)
Here are a few pics of the flange mounted to 2 freewheels. Each freewheel can be driven independent of eachother (one for pedal drive, one for engine drive)
Looks like they wont fit on the std 100mm front wheel.
Will fit the 110mm front or on a rear wheel (or could spread a pair of steel forks to fit a std front.
-Low-
 

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I'd like to see someone come up with a disc brake caliper that would work on the rag-joint sprocket --- the chain would actually go through the caliper, but the pads would clamp on the sprocket.
 
xseler,
Only trouble with that might be the flying chain oil getting onto the brake?
Chains are messy
-Low-
 
KC,
I am solely a 2-stroker at the moment.
-Low-
So how do you plan to start your bump start 2-stroke if the motor drive freewheels?

I had a repair earlier this year of a DIY bike and he put this freewheel hub in the back.

http://www.gasbike.net/bike-motor-engine-heavy-duty-axle-kit-free-wheel.htm

A nice hub with band brake and sprocket mount for $50 but he bought the freewheel version sprocket for the pull start 4-stroke for the motor side and not this one.

http://www.gasbike.net/bike-motor-engine-heavy-duty-axle-kit-non-free-wheel.htm

These hubs have 3 threaded sprocket threads. It is not a coaster brake freewheel hub.

To make matters worse once I fixed that I found he used a fixed sprocket for the pedal side so the pedals didn't freewheel, hence the pedals beat your legs to death under power.

All I'm saying is consider how you are going to start your 2-stroke bike.
 
So how do you plan to start your bump start 2-stroke if the motor drive freewheels?

I had a repair earlier this year of a DIY bike and he put this freewheel hub in the back.

http://www.gasbike.net/bike-motor-engine-heavy-duty-axle-kit-free-wheel.htm

A nice hub with band brake and sprocket mount for $50 but he bought the freewheel version sprocket for the pull start 4-stroke for the motor side and not this one.

http://www.gasbike.net/bike-motor-engine-heavy-duty-axle-kit-non-free-wheel.htm

These hubs have 3 threaded sprocket threads. It is not a coaster brake freewheel hub.

To make matters worse once I fixed that I found he used a fixed sprocket for the pedal side so the pedals didn't freewheel, hence the pedals beat your legs to death under power.

All I'm saying is consider how you are going to start your 2-stroke bike.

Interesting hubs, - I didn't know anything like that was available.
 
KC,
I dont bump start any of my engines...All use a pullstart and centrifugal clutch.
-Low-
That explains it and a nice benefit, nice job.
You must like the setup, you have to replace the cranks for wider ones like a 4-stroke correct?
Do you buy your engines that way or do it yourself and about how much more does it add?
I am curious because if the extra costs and work to do a BB to make a 2-stroke a pull start cent clutch I would take a 49cc 4-stroke over that stock 66cc 2-stroke most every time as they have the same mid 30's speed and so many more benefits.
 
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The Japanese engines I own were all bought that way (I never owned a China kit engine).
For mounting in frame, you need a longer bottom bracket axle.
-Low-
 
Good to hear from you CB2.
Brunswick is a hike and a half from here.
I don't get out much like I once did with the motorized bicycle.
Now just ripping (or posing) through my neighborhood & stopping by the post office on it once in awhile.
-Low-
 
You should check out choppersus(cyclesus ?) low. Pretty sure they sell a double disc hub. And statoninc has double sided freewheel hubs,if that helps.
 
d gizzle
I was trying to make a conversion for no cost. I haven't gone any further with it, but may try to convert a coaster brake rear wheel to this type setup to use a band brake on it.
-Low-
 
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