Some help please guy's.

I have just had a British hub co hub c/w with cushdrive assembly restrung with stainless spokes and a new Morad 2.15 alloy rim. All looks lovely with new sprocket and hub powder coated etc etc.

However when offered into the James Captain K7 frame and swingarm with the rear drive sprocket aligned to the engine sprocket, the centre of the tyre is about 1" offset to the right of the frame, making the wheel offset to the centre line of the frame.

There is an element of adjustment that I have made with spacers etc, but to get the wheel centralised to the centre line of the frame means that the chain is misaligned to the engine drive sprocket.

I was assured that the hub was suitable for my project, however I now have doubts and am also a significant amount of money out of pocket if it's no good??

Is there anything that can be done?? Should I be using a grimeca style hub instead?? Any advice appreciated.

Cheers.

Some help please guy's.

I have just had a British hub co hub c/w with cushdrive assembly restrung with stainless spokes and a new Morad 2.15 alloy rim. All looks lovely with new sprocket and hub powder coated etc etc.

However when offered into the James Captain K7 frame and swingarm with the rear drive sprocket aligned to the engine sprocket, the centre of the tyre is about 1" offset to the right of the frame, making the wheel offset to the centre line of the frame.

There is an element of adjustment that I have made with spacers etc, but to get the wheel centralised to the centre line of the frame means that the chain is misaligned to the engine drive sprocket.

I was assured that the hub was suitable for my project, however I now have doubts and am also a significant amount of money out of pocket if it's no good??

Is there anything that can be done?? Should I be using a grimeca style hub instead?? Any advice appreciated.

Cheers.

Sounds like the wheelbuilder didnt rebuild the wheel to the correct offset which of course you gave him before it was rebuilt didnt you? One other thing a 2.15 sounds a bit wide for the rim is that the correct size ? Would a 1.85 have been more suitable?

Edited September 22, 201114 yr by Old trials fanatic

Old Trials Fanatic.

As the hub was a bare hub, I was unable to determine the original offsets. I asked the wheel builder if this would be a problem and they said no as long as they knew the type of hub ie: full width, single sided etc. They did give me the option of either 1.85 or 2.15. I asked if it would make any difference and the reply was no, the wider rim would allow for wider tyres, but as the tyres are all of standard size it made no difference??

Hi Paul

Who built your wheel for you ?

1.85 is the more common size at the moment but who knows.

Might be possible to pull the rim a bit, but probably not as much as an inch.

Ross

Old Trials Fanatic.

As the hub was a bare hub, I was unable to determine the original offsets. I asked the wheel builder if this would be a problem and they said no as long as they knew the type of hub ie: full width, single sided etc. They did give me the option of either 1.85 or 2.15. I asked if it would make any difference and the reply was no, the wider rim would allow for wider tyres, but as the tyres are all of standard size it made no difference??

For future reference it's always best to fit the hub into the frame and get the chain alignment right first then it's easy to determine the offset for the rim. On a lot of old bikes there is very little clearence between the chain and a 400 x 18 trials tyre so sometimes, like on cubs, you have to move the engine over slightly in the frame and add a spacer to the rear sprocket. Either way fit the hub. Check alignment. Measure offset and only then get the wheel built. I would have chosen a 1.85 rim for better chain clearence. Your wheelbuilder doesnt seem to know his stuff IMHO.

Edited September 22, 201114 yr by Old trials fanatic

Hi Ross.

It was Central Wheel Components down in Birmingham. I will take a photo when I get back home from Offshore and send it down to the guy at Central and see what he say's??

As it stands just now with the drive sprocket and cushdrive being a separate unit from the actual hub, it would appear to me that little can be done. Therefore if I need to start from scratch again what is the best rear hub to be using, Grimeca conical like what was used on the old Greeves etc??

Before giving up speak to George Spence in Cupar, he will give you a definite answer.

I'l dig out his phone number if you want.

Ross

Aye Ross.

I could maybe send him a couple of photo's showing the situation anyway, and then see what he say's. Otherwise looks like I will have to start from scratch again and try sell this one on. Must be of some use to someone??

Cheers.

Paul.