On my '69 firebird I've recently put in new clutch springs, because when kickstarting the clutch slipped. However it still slips when kicking over, the old springs were 1-2mm shorter than the new ones. Clutch plates were in good order and thick enough. Filled with 10-40 oil.
Is this a common problem - when kicking on compression stroke? or maybe the clutch plates are soaked in oil?
Any advice appreciated.
I'm sure you've checked already, but clutch pushrod free play?
Hi,
What type of 10/40 oil? Additives in modern oils will cause slip. Wet sump modern bikes use the engine oil through out but the clutch and oil are designed for this.
I have used ATF for many years and thousands of miles and it works well.
If after checking the clutch rod clearance, as suggested, try draining the 10/40 oil out and replace with ATF. If you can get the bike running the 10/40 may then clear from the plates. Otherwise it may be necessary to strip the plates out for a clean.
Dave.