sac02052
XS650 Member
Bike reference - 1981 XS650 H, 19081 miles, purchased in the last month with unknown maintenance history. With normal "new to me" maintenance, the bike now starts and idles fine, carbs thoroughly cleaned, valve clearances adjusted, etc. Cam chain tensioner is flush with +/- 1 mm travel when hand cranking the engine.
When idling it does sound like there is metal-metal contact, so I suspect it has a worn cam chain guide. I have a video of the bike idling, but sound quality is poor and everything sounds tinny on my crappy laptop speakers. There were a few small Al bits in the smaller clutch case filter last oil change, but I didn't see any large black plastic chunks in the sump.
I've searched the forum and read the various threads, but still have three questions ...
1. Is there any way to visually inspect the guide without a major tear down? I've removed cylinder heads before, but I'd rather not have to pull the engine and undo/reset the cam chain timing unless necessary. Looking at the engine images, I suspect the answer is "no, you can't inspect the guide without tear down".
2. Should a guide of that vintage and mileage should be replaced regardless of wear? I suspect the answer is "yes".
3. Is it OK to start and idle the engine for relatively short periods to test other aspects of the engine?
Thanks for listening as I talk through this.
When idling it does sound like there is metal-metal contact, so I suspect it has a worn cam chain guide. I have a video of the bike idling, but sound quality is poor and everything sounds tinny on my crappy laptop speakers. There were a few small Al bits in the smaller clutch case filter last oil change, but I didn't see any large black plastic chunks in the sump.
I've searched the forum and read the various threads, but still have three questions ...
1. Is there any way to visually inspect the guide without a major tear down? I've removed cylinder heads before, but I'd rather not have to pull the engine and undo/reset the cam chain timing unless necessary. Looking at the engine images, I suspect the answer is "no, you can't inspect the guide without tear down".
2. Should a guide of that vintage and mileage should be replaced regardless of wear? I suspect the answer is "yes".
3. Is it OK to start and idle the engine for relatively short periods to test other aspects of the engine?
Thanks for listening as I talk through this.
Last edited: