It's been a few months and I hadn't touched the carbs. Finally had the opportunity to pull the carbs and replace the pilot screws, springs, o-rings, and washers. Backed them out 2.5 turns and fired her up. She was idling a little smoother but still backfired/popping and was still smelling fuel. So I tried 1.5 turns and she ran a little rougher and popped more.
Today I tired to adjust the pilot screws again. Tried 3 different adjustments, all having the same result. 2.5 turns, 1.5 turns, 2 turns, and finally 2.75 turns= revving to 5k, no popping/backfiring at idle; test ride resulted in bogging down (almost shutting down) at WOT, slowly rolling throttle only gets me to ~4k rpms.
So, do I need to back the screws out 3 or more turns? Do I need to rejet the carbs now?
The pilot screws are for setting the idle mixture. A good tuning method is to tweak them until the highest idle speed is achieved. These screws have an effective range of 1-4 turns out and the further out the richer the mixture.
FYI (in case this applies): If you are running pod filters the carbs will need drastic rejetting. The pilot screws won't help you much there.
Been a while since I messed with the 440. Bought a sync tool from Amazon and used it tonight. I was hoping that all I really needed to do was resync the carbs but, that wasn't the case. They were already synced! So now I think it's either a jetting issue, not enough back pressure in the exhaust, or both. What do y'all think?
The pilot screws are for adjusting the low speed mixture, from idle to about 1/8 throttle opening. As the throttle is opened father, the other circuits come into play and the pilot screws have less and less influence. Since you are having problems throughout the rev range, either there are multiple problems with the carbs, or the problem is elsewhere. You mentioned back pressure in the exhaust system. Has it been modified?
1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough
The carbs have been cleaned twice already. As for the exhaust, its a 2 into 1 (Mac I think) without/missing the baffle. I installed 2 small universal baffles in the end of the header tubes hoping it would help.
I should also add that I swapped the modified air box I made for a stock one and the idle was a little smoother.
Spent a lot of time today looking around eBay, Amazon, and a ton of parts dealers for a carb jet kit and baffle to fit in the exhaust. Finally found a baffle that might be an actual MAC replacement! As for a jet kit, I'm still looking. I've found a few that look promising but I'm still not sure.