Honda-SOHC
SOHC.co.uk Forums => CB500/550 => Topic started by: Neilw on July 31, 2026, 10:16:24 AM
-
Hi,
Just got round to fitting the top of the engine, and as I was fitting the camshaft sprocket, a bit of hard plastic flaked off. On examination, a larger bit had previously come off, and I can see there is a small crack in the plastic on the reverse side. The rest of the plastic and sprocket is fine, but it is clearly a weak point.
Are there replacement parts available, as a quick look suggests they are not easily found? I guess secondhand sprockets would have the same age-related weak point! OR could / should I just chip off the loose bits and reuse the existing sprocket?
Seems to be one step forward, two backwards with this bike :-) lol
Thanks for your wisdom and help.
CB550 1978 F2
-
My thoughts are sometimes in the past a PO has had problems refitting the chain and used a screw driver to lever it on,
Obviously a better condition sprocket would be ideal,
But you could tidy up the broken ends using a file,radius the sharp edges, and refit
The plastic looks secure, so shouldn't be an issue.
Sent from my SM-A546E using Tapatalk
-
I remember when I was fitting my new camchain on my 500 it took me a while to work out the correct assembly order to avoid using a lever to get the chain in place.
Iirc Ken advised me how to do it, one of those things thats difficult to understand from a manual.
My struggle is documented on P40 of my 500K1 project - link on my rebuild below.
-
The shroud was fitted IIRC to stop the sprocket resonating, as in making a ringing noise. A small piece missing will do nothing detrimental IMO. Same applies to the front drive sprocket on a lot of bikes.
-
Thank you all; it confirms what I was hoping for.
I've spent 6 hrs today fitting the chain to the sprocket - it's driven me mad, and I avoided using tools to prise it on. Another difficult aspect was getting the sprocket seated on the cam after I had the chain on - this took a few hours of fiddling - eventually I eased it on using the fixing bolts. All done now!
-
Well done Neil, they are fiddly, I was always mindful not to drop a sprocket fixing bolt into the engine when I did mine.
-
Well done Neil, they are fiddly, I was always mindful not to drop a sprocket fixing bolt into the engine when I did mine.
Same. I have perfected the art of dropping something and it just disappearing on the floor. I hate to think of the number of hours I've wasted looking for springs, nuts and bolts. I'm taking up a new sport - magnet fishing!