I have a 1978 CB750F with a lightweight (200LBS) Cozy sidecar. Originally the 78 came with a 630 non O-ring chain and 14T/43T sprockets.
I'm converting to a 530 X-ring chain and the closest sprocket ratio I could get was a 17T/48T set, which was standard on this bike for many previous years.
Am I making a mistake? What I mean by that is do you think I will be adding undue stress to the engine and clutch by changing the ratio from 3.07 to 2.82 or 8.8%?
Pillage,
Could depend on how strong the clutch is, is original or upgraded? How much weight do you plan on carrying in the sidecar.
Have you considered a 525 16T countersprocket? A 16/48 would give you a 3.00 ratio.
The clutch is solid. 60% of the time I have only 70LBS of balast in the sidecar, 40% up to 200LBS (passenger & gear). I've had no problems going from an uphill stop. Although I did take a 300LBS passenger for a short ride recently and my machine was definitely stressed when starting uphill from a stop. I won't do that again, as I was also stressed knowingly overloading my precious bike & sidecar. I'm currently not able to ride a two wheeler, and having this sidecar has kept me on the road and very happy!
I have a brand new 530 x-ring chain (purchased for a bike I subsequently sold). I was looking for a cheap way out, by converting to 530, which is a common for 77-78 CB750F's. All other Gen 1 CB750's had 530 chains and between 2.7 to 2.8 sprocket ratios. I like your 16T suggestion and will try again to find one, before I install the 17T.
