Sprocket too big for hub...what to do?

[Kristof]

Hi,

I ordered a sprocket and mount from ebay for about $17 and the sprocket is a little too big for the hub.

Will the rubber discs hold it center or do i have to have it against the hub? Do i even have to have it against the hub?

In this picture it has the rubber disc in there:

 

[2door]

Getting it centered is one of the challenges of the installation. In fact it is probably the most important aspect. Find a way to free rotate the wheel, Spin it and watch it. Center the sprocket by light taps with a plastic mallet or a hammer and a piece of wood against the sprocket teeth. Most if not all sprocket center holes are larger diameter than hubs. It's up to the installer to center it.
Warning: It MUST be centered. No wobbles up and down or side to side, to keep the chain from coming off. Keep working. You'll get it.
Tom

 

[Kristof]

Most if not all sprocket center holes are larger diameter than hubs. It's up to the installer to center it.

Thats what I was looking for, thank you so much.

Another question, will the rubber disc inside the spokes have to be cut in order to fit around the hub? And, what are the torque specs for the bolts...if there are any?

 

[2door]

There should be two rubber discs. One goes on the inside of the spokes, the other toward the outside. Yes, you'll need to make a slice in one of them to fit over the hub. Make the slice between the bolt holes.
The stack, or arrangement of the parts from the in side out is: Metal plates, rubber, spokes, rubber, sprocket. In that order. Good luck. Let us know if we can help further.
Tom

 

[Kristof]

Ok, thank you. So there are no torque specs.?

If there are none, could you suggest a torque. I have access to a torque wrench at my school auto shop and I would like to use it on a crucial part of the build.

 

[Venice Motor Bikes]

. Make the slice between the bolt holes.

I always make the slice through a bolt hole! This way there's a solid piece of rubber right behind the spokes where they cross.

 

[Kristof]

I always make the slice through a bolt hole! This way there's a solid piece of rubber right behind the spokes where they cross.

So which is better? lol, start a thread on this...?

 

[2door]

Venice and I usually agree on most things. I've never done it his way but you can be sure it will work. Personally I've never had a problem doing it my way so now the ball is in your court. I will tell you that he has built more bikes that I have if that's any help. No need to start a new thread. Just take your pick and use what seems right to you.
Tom

 

[Goat Herder]

I always make the slice through a bolt hole! This way there's a solid piece of rubber right behind the spokes where they cross.

I concur with Venice..

 

[zean]

Hi Kristof. The torque specs for the bolts? Tighten the bolts in a (I think they call it a criss cross pattern) a little at a time just until the two black rubber discs first come together and there is no air space between them.