Kerker 4-1 canister pipe
Pod filters
Stock carbs
137.5 main jets
47.5 pilots (stock size)
Stock needles in #3 of 5 clip position
Mixture screws at 2 1/4 turns out
Cams degreed to 110/109 intake/exhaust lobe centers (stock settings)
Much to my satisfaction it started on the second touch of the starter button, with a bit of choke. That was Saturday night about 11:30pm, so I left it at that and then went for a ride yesterday.
It started from dead cold in cool temps (12C/54F) with a bit of choke and needed maybe 10-15 second of part choke before idling nicely at 1200rpm while warming up. Definitely not cold blooded at all. I put a strip of tape on my throttle with 1/8, 1/4, 3/8, 1/2, etc. marked so I could see where I was at on my carb circuits and headed out. It runs very nicely on the pilots, with no lean surging or hesitation when I roll on or whack it open at once. Running at 1/8 throttle and pulling the choke causes a bit of a bog, so I think I am fairly close on the pilot circuit. Lots of popping on deceleration, though, so I am not that rich...
It pulls nicely onto the needles and under steady running at 1/4-3/8 throttle pulling the choke will also cause a bog, so I think I am pretty close there as well.
I didn't get a good read on the mains, as a misfire begins about 6000rpm at full throttle and it will not pull through this area. If I sneak up on 6000rpm at lower throttle settings (say 1/2-5/8) it will pull through, but not happily. I think I have a coil going south because it did this last year as well when the jetting was well sorted with the modified airbox in place. I may be a touch lean on the mains as well (beyond the electrical issues) and will probably try 140's just to see what that does.
I pulled the plugs last night and there were hardly any deposits at all (is this normal after ~70km?), but what was there was decidedly light in color, so I think I may be on the lean side of perfect by a touch. This week I plan to back the mixture screws off to 2.5 turns out and raise the needles one notch to see what happens.
But it generally ran so well I was amazed. I figured I had a couple of weekends of farting around to get it running well enough to trust it before I could expect to ride to work or anywhere else, but it was fine yesterday with no real issues at all.
Any comments on my jetting process and/or advice/ideas on where to go with it next?
Mark
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