09-11-18, 09:35 PM
When you say you swamped diaphragms I presume you mean with the carb pistons as well, and checked they are moving freely. I can’t see that the butterfly valves would have got out of sync but might be worth making sure they are all moving the same amount. With one cylinder not firing a vacuum test won’t be much use .Good idea to do a compression test after it has run with all cylinders firing so as to clear any unburned fuel from the cylinder, even if you let it cool down, but without letting it tick over again. If compression still down on no. 3 I would first check valve clearances. Can’t think of anything else at the moment. Hope you get it sorted and would be interested to know the result.
By coincidence I measured the temperature of the exhaust pipes on my 600 the other day and at tickover from cold no3 cyl. was 100C and the other three were 135C. A few minutes at 2000 rpm and all four pipes showed 200C. Bike runs fine and sounds good at tickover but I’d like to find out why one cylinder runs cooler when I get time to investigate. If I hadn’t been playing about with my infra red heat gun I would never have known and just enjoyed the bike.
By coincidence I measured the temperature of the exhaust pipes on my 600 the other day and at tickover from cold no3 cyl. was 100C and the other three were 135C. A few minutes at 2000 rpm and all four pipes showed 200C. Bike runs fine and sounds good at tickover but I’d like to find out why one cylinder runs cooler when I get time to investigate. If I hadn’t been playing about with my infra red heat gun I would never have known and just enjoyed the bike.