The place to come to share your technical expertise, or just find out what the little springy thing is that's just pinged out of sight under the work-bench.
I am having a few carb issues, mainly low down. I did checked the jets for markings and they do say(I think) .45. However,I used some small drill bits to gauge the actual size as i suspect they have been messed with and got a drill in that was 1.32 mm with wiggle room!!!
The one I am referring to is the one on the right of the picture, the one on the left was blanked off when i got the bike?
It has had new needles/jets, carb rubbers, balanced, float heights at 14mm etc.
It has always had a below 3000 revs issue, especially when pulling away - spits/fart/jumps etc. Once it is over 3000+ it is a lot better but the air screws were out to 3.5 turns.
The bike did have a dynojet kit on when i got it, but removed that to get back to standard and that where the blanks were from, i put them back in to see if that would help but made it worst so they are back out now. I'm also not sure if they drilled any jets when fitting the DJ? I since found that the markings on the jets are flow rates so i don't know how i can measure to check they are correct so i will have to buy new jets.
Which ones are the slow running jets?
I'm also getting conflicting jet sizes from the manuals, some say main jets 120 across the board, others say 125 & 122.5? Not sure which ones to believe?
I have not checked the chokes?
Thanks again, i'll investigate the jet issue first.
Generally the middle 2 jets will be larger due to those cylinders running hotter due to less air flow
The slow running is controlled by the pilot circuit. Even a small blockage will cause havoc as I found out last year. I'd ultrasonic cleaned my carbs and stripped and cleaned them out but issue persisted
Nuggitt & Roadrunner came to my assistance. We stripped each carb back to basics, cleaned with carb cleaner and blew everything out with a high pressure air gun. With rubber tip to help seal things. It's ran correctly ever since.
Looking at a couple of references my main jets are 120 across the board. My slow running ones say #45 but the manuals say 60 & 120 so hopefully that may sort it?
So far the passages look clear, just need to blow them through.
I did notice when I took the carbs off that no1 carb was looking black in the Venturi??? That pot as been spitting and popping - any ideas?
it's a silly question I know but have you checked the spark plug on #1 cylinder? Sounds to me as though the plug is playing up. Snip a bit off the ht lead and screw the cap on nice and tight. It could be contributing to some of the problems you're having.
Bit of advice. Buy a good bed and a good pair of shoes, because if you aren't in one you'll be in the other.
