3 speed hub

[jtbarnes89]

i am just wondering if anyone has ever done a 3 speed rear hub on a motorized bike??? im wondering if it is strong enough to handle the torque.. i used to have a tall bike with one and it seemed pretty strong but idk

 

[SimpleSimon]

i am just wondering if anyone has ever done a 3 speed rear hub on a motorized bike??? im wondering if it is strong enough to handle the torque.. i used to have a tall bike with one and it seemed pretty strong but idk

To answer your questions - yes, and yes.

The multi-speed internal shifting hubs are engineered for much higher stresses than any small engine is going to put on them. The only real issue is with the 7,8 or higher number of gears hubs and vibration transmitted through the chain line from the engine. The higher the number of gears, the thinner the internal discs in the hub. Vibration on the very thin discs can start slipping.

 

[jtbarnes89]

To answer your questions - yes, and yes.

The multi-speed internal shifting hubs are engineered for much higher stresses than any small engine is going to put on them. The only real issue is with the 7,8 or higher number of gears hubs and vibration transmitted through the chain line from the engine. The higher the number of gears, the thinner the internal discs in the hub. Vibration on the very thin discs can start slipping.

wat would be a good size that wont slip?? i have a 26 inch cruiser with a 66cc grubbee with a 36 tooth rear sprocket

 

[SimpleSimon]

wat would be a good size that wont slip?? i have a 26 inch cruiser with a 66cc grubbee with a 36 tooth rear sprocket

Well, let me ask - are you proposing to add a jackshaft and combine the pedal side and power run in one chain loop? If so, I'd recommend the Sick Bike Parts jackshaft kit, and whatever internal hub you want to use. Properly installed, the jackshaft should isolate the worst of the vibration pretty well, and the rear multi-speed huib will simply function as normal.

 

[skrufryder]

i'm looking for a 5-7 internal hub with disc brake anyone ever see one?????

 

[jtbarnes89]

Well, let me ask - are you proposing to add a jackshaft and combine the pedal side and power run in one chain loop? If so, I'd recommend the Sick Bike Parts jackshaft kit, and whatever internal hub you want to use. Properly installed, the jackshaft should isolate the worst of the vibration pretty well, and the rear multi-speed huib will simply function as normal.

well if i do that then i wouldnt be able to pedal and 2nd i would just go with a regular shift if i did that.. the reason i want the internal hub is to be able to shift gears and have a sprocket mounted one one side and a free spin hub to peddle with on the other

 

[HeadSmess]

ive been pondering the thing for a while...

problem with hubs for pushies is the drive is on the right, and for a gear shift to work solely on the engine...it would need to be on the left... i havent bothered checking but im assuming these "shift kits" are a jackshaft that then drives the cranks...yuk. the idea just sounds horrible.

on the other hand...if you got a shift kit,and drove the 3 speed hub directly, with a free wheel mounted on the left hand side for pedalling (like some bmx bikes now have the chains on the left!) it would be fairly simple, with only the need for a thread to be machined on the hub to take the left hand freewheel...


then...how do you start? theres a freewheel there! in the 3speed hub!

(ive thought of that too...a recoil spring starter? roll back a bit, then...yeah)

work out how to actually pull one apart and jam its pawls up so it cant freewheel

im gunna do this now... and do i have the bike?
oh yeah !
but iunno.

ive been told that gear hubs dont take too much torque at all... and ive found a few old ones that have obviously chewed out...shimano suntour, sturmey archers...etc...and not from motors, id say...

 

[HeadSmess]

and note that with gear hubs...you are meant to stop pedalling briefly when shifting...unlike them brutal derailleur setups...

you may want to use the clutch on the shifts...

 

[Ghost0]

Lots of our customers have used internal hubs with mostly good success. They tend to fail if they are not adjusted correctly or if abused during shifting.

 

[jtbarnes89]

ive been pondering the thing for a while...

problem with hubs for pushies is the drive is on the right, and for a gear shift to work solely on the engine...it would need to be on the left... i havent bothered checking but im assuming these "shift kits" are a jackshaft that then drives the cranks...yuk. the idea just sounds horrible.

on the other hand...if you got a shift kit,and drove the 3 speed hub directly, with a free wheel mounted on the left hand side for pedalling (like some bmx bikes now have the chains on the left!) it would be fairly simple, with only the need for a thread to be machined on the hub to take the left hand freewheel...


then...how do you start? theres a freewheel there! in the 3speed hub!

(ive thought of that too...a recoil spring starter? roll back a bit, then...yeah)

work out how to actually pull one apart and jam its pawls up so it cant freewheel

im gunna do this now... and do i have the bike?
oh yeah !
but iunno.

ive been told that gear hubs dont take too much torque at all... and ive found a few old ones that have obviously chewed out...shimano suntour, sturmey archers...etc...and not from motors, id say...

im gonna do it but where i live no shop will sell the three speed hub or wheel.. so im going to have to find a used one and true the wheel and grease it and keep the one i have now for a spare incase i destroy the three speed