Hello, I've been following this thread for quite some time but I'm still struggling to get the bike running good. So I thought I'll explain my problem here.
My bike is definitely running lean. I've had it running ok after engine rebuild however it was running very hot. I can't do WOT tests yet since it has new rings and I don't want to seize it since its realy getting hot.
Bike is 77 550k with PD46A carbs, MAC 4in1, Uni air filter, stock airbox, Dyna S with stock coils.
The bike was running ok, no problems with idle etc however was overheating, I've checked boots for the carbs for leaks and they seem ok. Afert the initial run 2 header pipes showed signs of Overheating (brand new pipes, cyl 2 and 4 got tan color, 1 and 3 no color change). I was running the bike and it ran much better wit choke fully pulled.
I've pulled out carbs today and cleaned them and got complete rebuild (slow and main jets, new needles, new needle sets etc), new boots on the engine side (with a bit of luck maybe I'll find the aibox side ones but as someone already mentioned those were part of the aibox and not sold separately)
Manual says that for 550K3 neede should be on 3rd groove (2nd groove for 550) for this carb. (appendix of the manual for 550k3) . Previous needles were set on 2 nd groove.
I had limited time to start the bike, I had iddle screws 1,5 turns out and the bike wouldn't start, Ive replaced Uni filter with stock one and got similar results, then I've pulled out air filter and put a cloth in the intake mostly blocking it, bike started and got the idle working ok. Right now I'm running 90 main jets, I was planing to go 95 but need to get feedback after carb rebuild.
One thing that is noticeable is tha throttle response got much much better in mid range (engine picking up revs much quicker) after rebuld, however when I pull out full choke on warmed engine it has no effect.
I know this is a lot of information but I'm not experience menchanic and this is my first carb rebuild and try to get carbs runnig good.
The biggest thing is why the bike doesnt run on stock filter and runs on blocked aibox, however puling choke has no effect. I'm going to try again fresh tomorrow and check everything again for intake leaks etc and maybe try to get it on the road and see how it runs, carbs were bench synched, I havend plugged vacumeters yet since there is no point until at least it runs kind of ok.
Quick question on the iddle needles, the have a spring, washer and rubber oring, what is the order of thise, oring goes between spring and washer or it should be oring, washer, spring?
I'll try to post some more information tomorrow after I get some time and try to run it.
Thank you, any help would be appreciated.
Update:
Ok I cant get the bike to start normally, When I spry something flamable into airbox it will start running then it iddles ok one it warms up. However slightest touch ouf throttle or trying to increase idle with iddle screw above 2k the bike starts to cut of, I got it to above 5k on spray and when stop it just dies, no iddle I've pulled out the plugs and they were fouled so I'm running rich, I think it might to do with needle raised by one groove to 3rd position from 2nd (from top), However that just seems to quickly to needle to kick in. Maybe the new needle is slightly different and allowing more gas ealier. I'm going to raise it a bit and see how that goes. I think the pilot jet is ok since it iddles, but again trying to touch the throtle by 1/20 in will cause the bike to bog and if I dont release it it will die. I've pulled out the filter and try playing with a cloth with some success, got the bike reving on gas but as soon as I let go it shuts of it just looks that its going super rich if needle is even slightly pulled up
Thanks