Paddywagon Chainring inside or out?

attica

I bought a Kona Paddywagon, it came with the chainring on the inside of the crank assembly and a very heavy looking steel plate on the outside as a chainguard.

Obviously I've dumped the superfluous chainguard but now have a strange looking "chainring on the inside" type beast.

Question is, can I bring the chainring to the outside of the assembly without causing extra chainwear or any other problems I've not thought of.

david 142

The primary consideration is the chainline. If chain ring and sprocket do not line up pretty precisely you will get rapid wear, noise and the risk of the chain coming off.
Moving a chain ring to the other side of a spider will put it, what, 5 or 6 mm out of line? Thats far too much in a context where the use of a straight edge is advantageous!
You might get away with it if you can find a bottom bracket with a spindle that is shorter by just the right amount, if, that is, the spider doesnt catch on the chainstay...

attica

Thanks David

I thought as much.
Next question is, how do I modify it all in order to make it look nice and pretty?
Is it possible to somehow shorten the BB axle?
There's certainly plenty of spare space there.

david 142

No, you can't shorten it! You have to find and fit another bottom bracket unit with an axle just the right amount shorter. The existing one is probably marked with its size and the difference you would need equals the thickness of the ends of the spider arms plus the thickness of the chain ring. Thats just a starting point of course - you might end up having to get clever with shims and washers :shock: