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I've rebuilt my XL800 engine including the carbs over the winter thanks to this forum, You Tube and a number of others. The break in isn't complete on the engine yet. It starts nicely with the use of the new primer line I installed but it idles roughly and will stall if I don't keep a bit of extra gas on. I would estimate the idle RPM to be about 1300 which I think is where the factory would want it to be. At 2000 it won't stall. Not sure I can control it to much less than 2000 reliably.
Could this be intrinsic to poor pop off pressure consistency I noticed during the carb rebuild?
During the carb rebuild I had a terrible time getting consistent pop off pressure results. I could get 60 psi and then 40 psi. Sometimes it was like I pumped up the pressure too quickly and other times it didn't seem to matter. The first set of needle and seats were SBT brand. When I called SBT they determined they must be bad. The tech was fantastic, determined they must have had a bad batch so he ran a test on needle and seats till he found a set that would give him consistent results and he sent me those. I tried them an like a bumpkin couldn't make them work. I bought a batch of Yamaha/Mikuni needle and seats which seemed to be more predictable, enough so I could trim the springs a bit and pretend I was doing it right. I wanted to be consistently within 2 psi but I think I settled at about 5 psi, and I can't say that was really consistent but more a trending pattern.
Might this rough idle improve over time during the engine break in?
If I adjust the low speed needle on the carbs will that increase the idle speed? Is that a potential solution to avoid pulling apart the carbs and redoing?
Any other thoughts on the rough idle on a fresh rebuild?
Thanks!
Could this be intrinsic to poor pop off pressure consistency I noticed during the carb rebuild?
During the carb rebuild I had a terrible time getting consistent pop off pressure results. I could get 60 psi and then 40 psi. Sometimes it was like I pumped up the pressure too quickly and other times it didn't seem to matter. The first set of needle and seats were SBT brand. When I called SBT they determined they must be bad. The tech was fantastic, determined they must have had a bad batch so he ran a test on needle and seats till he found a set that would give him consistent results and he sent me those. I tried them an like a bumpkin couldn't make them work. I bought a batch of Yamaha/Mikuni needle and seats which seemed to be more predictable, enough so I could trim the springs a bit and pretend I was doing it right. I wanted to be consistently within 2 psi but I think I settled at about 5 psi, and I can't say that was really consistent but more a trending pattern.
Might this rough idle improve over time during the engine break in?
If I adjust the low speed needle on the carbs will that increase the idle speed? Is that a potential solution to avoid pulling apart the carbs and redoing?
Any other thoughts on the rough idle on a fresh rebuild?
Thanks!