Shifting with Internal Gear Hub ??

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phyrstorm

New Member
Hello again!

Im thinking about taking an alternate route to a shift kit.

If I get a Hub with Internal Gearing, could I mount a drive sprocket directly to that internal gearing?

Ideally this would allow me to gain the ability to shift gears without all the extra sprockets and derailleur.

I am just not sure if this would actually work and how I would go about it. I can get the Hub with Internal Gearing, then would I maybe be able to get the HD Axle Kit (blowbyu.ca) and mount a sprocket onto my hub?

If anyone could shed some light on this I would appreciate it~

Thanks!

.duh.
 
The Sturmey S3X can work backwards, as it's a fixed-gear hub, but there isn't any mount for a sprocket on the other side. Just the one side.

A shift kit or custom jackshaft arrangement is just about the only option if you want to route the engine through gears.
 
i think this is what you mean the strumy S-RK5(N) 5 speed has a disk brake bolt pattern so you can put a drive sprocket on it on the left
 
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The_Aleman said:
The Sturmey S3X can work backwards, as it's a fixed-gear hub, but there isn't any mount for a sprocket on the other side. Just the one side.

A shift kit or custom jackshaft arrangement is just about the only option if you want to route the engine through gears.
Click to expand...

I think this would work for me... I dont pedal much as it is and with my current gearing applied to the SA S3X ill get a much wider range and easier take off...

At the moment I have a 12tooth freewheel on engine and 44tooth rear sprocket, take offs are a bit taxing(can still get moving with a push off) but top end is good. I think I could get a 44tooth to fit the SX3 and customize a freewheel for the blank side, or just do without pedaling....

HuaSheng 4stroke SIII 3.7:1 -~- 3.66:1 giving 17mph - 45mph
SA SX3 (fixed hub used on left side): 3000rpm ---> 7800rpms
1st gear- 62.5%:: ~10.5mph ---> ~28mph
2nd gear-75%:: ~13mph ---> ~34mph
3rd gear-100%:: ~17mph ---> ~45mph


.xx.
 
JonnyR said:
i think this is what you mean the strumy S-RK5(N) 5 speed has a disk brake bolt pattern so you can put a drive sprocket on it on the left
Click to expand...

No. OP wants to route the engine through the gears, a disc brake mount doesn't use gears. The brake is not connected to the gears, derp.

phyrstorm said:
I think this would work for me... I dont pedal much as it is and with my current gearing applied to the SA S3X ill get a much wider range and easier take off...

At the moment I have a 12tooth freewheel on engine and 44tooth rear sprocket, take offs are a bit taxing(can still get moving with a push off) but top end is good. I think I could get a 44tooth to fit the SX3 and customize a freewheel for the blank side, or just do without pedaling....

HuaSheng 4stroke SIII 3.7:1 -~- 3.66:1 giving 17mph - 45mph
SA SX3 (fixed hub used on left side): 3000rpm ---> 7800rpms
1st gear- 62.5%:: ~10.5mph ---> ~28mph
2nd gear-75%:: ~13mph ---> ~34mph
3rd gear-100%:: ~17mph ---> ~45mph
Click to expand...

Your math looks good. As far as running wthout appropriate pedal gearing, I think you'll be relying too much on motor.

Not pedaling is throwing away big torque, not to mention legality/exercise reasons. For example, syncing engine redline with pedal redline in a shift-kitted bike will prolly surprise you and the cars around you off the line ;)

JonnyR said:
i dont know if that will be enough reduction for a HS
Click to expand...

You never even seen a Huasheng in person, never run their transmissions, and therefore your theoretical/hypothetical thinking is simply too weak and inexperienced to even make a constructive comment, IMHO. That's called being an ultracrepidarian on the subject. Are you just trying to up your post count? :p lol
 
The_Aleman said:
No. OP wants to route the engine through the gears, a disc brake mount doesn't use gears. The brake is not connected to the gears, derp.
Click to expand...

... think again .,.. derp... ;)

The disk brake is attached to the hub... derp.

Drive the chain sprocket with your engine. Attach another sprocket to the disk. Drive the rear wheel with the output of the disk.(jack-shaft)

Was that so hard?
 
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bowljoman said:
... think again .,.. derp... ;)

The disk brake is attached to the hub... derp.

Drive the chain sprocket with your engine. Attach another sprocket to the disk. Drive the rear wheel with the output of the disk.(jack-shaft)

Was that so hard?
Click to expand...

My point is that driving the engine through the disc brake mount on the left side as part of the rear wheel will not use the gears, it is single speed conventionally. Your method is using the hub as part of the jackshaft itself.
 
I'm just not sure if the disc brake is actually mounted to the internals of the hub... and I don't have one to look at(which would be best) , but intuitively I would think it is mounted to the outer portion of the hub so it spins correctly, but has no association with the turning of the internal gears... but im no expert on that~ unless ya know for sure I will ask a bike shop mechanic how it works or to look at one

The fixed gear would be able to flip around though giving the motor access to the gears with no shift kit... which would be the best option if i could mod a freewheel onto the other side for pedaling.

Thanks for the info/suggestions
 
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