Re-jetting re-confusion

[Mace069]

Follow-up...better late than never

I'm sorry it's taken me so long to post my results. Here we go, we changed the main jets to 127.5 (good call, Keith) and we left the pilots alone. Yep, my mechanic said I would be just fine. I almost (89%) agree with him. I can tell you for sure, this bike runs it's ass off now and I love the satisfying WHOOSH! of air into the carbs when I wind it out. Over 3,000rpms, it's got gobs of power. At 7,000rpms I better have a good grip or I'll be looking at my own tail lights. Under 3,000, that's a little different. It seems to be a little (just a smidge) boggy. It's not lugging and there's no black smoke out the exhaust and it picks up fairly quickly to 3,000 then away we go. The K&N info states that a pilot jet change may be needed if performance lags under 1/4 throttle. At this point, I think I'll just live with it. Anyone have any ideas on how I can tell more definitively if a pilot jet change is necessary (ie. spark plug color). Oh yeah, I'm getting about 45mpg on the highway and 38mpg combined.

[KEITH KRAUSE]

I'm sorry it's taken me so long to post my results. Here we go, we changed the main jets to 127.5 (good call, Keith) and we left the pilots alone. Yep, my mechanic said I would be just fine. I almost (89%) agree with him. I can tell you for sure, this bike runs it's ass off now and I love the satisfying WHOOSH! of air into the carbs when I wind it out. Over 3,000rpms, it's got gobs of power. At 7,000rpms I better have a good grip or I'll be looking at my own tail lights. Under 3,000, that's a little different. It seems to be a little (just a smidge) boggy. It's not lugging and there's no black smoke out the exhaust and it picks up fairly quickly to 3,000 then away we go. The K&N info states that a pilot jet change may be needed if performance lags under 1/4 throttle. At this point, I think I'll just live with it. Anyone have any ideas on how I can tell more definitively if a pilot jet change is necessary (ie. spark plug color). Oh yeah, I'm getting about 45mpg on the highway and 38mpg combined.

Hi. Thanks for letting us know how it runs.
Pod filters WILL cause a small loss of torque at lower rpm's. If your lower rpm/smaller throttle openings result in a boggy performance beyond that, then it could be the pilot circuit or some overlap from the jet needle circuit. This assumes the valve clearances, timing, etc, are all correct.
Pods/pipe will require that the stock jet needle e-clips be at the bottom position if using stock needles. My experience says anything less (leaner) will be too lean and may cause bogging. Hard to say with limited info. Tests/plug chops at 1/3 throttle will tell more. Where are your clips??
It could also be related to the pilot jet and pilot fuel screw and side air screw adjustments and also the vacuum synch. If I remember correctly, you said you were running 22.5 pilot jets?? If so, and as I said before, you do not need larger than 17.5 pilot jets for your mods.
Also, where are the pilot fuel (underneath) and air screws set at? Are the 2 floatbowl vent lines removed and ports left open?

[KEITH KRAUSE]

One more thing after re-reading your post, 45 hwy mpg is common (maybe a little more than normal/slightly lean?) but if your combined avg is 38, that means you're getting approx' 31 city? 31 city suggests a rich pilot circuit unless you really ride it hard/very short trips.
I've always had good results by testing the pilot circuit at minimal throttle opening, just cruising around, level or uphill, for a few miles after complete warm up and chopping off and reading the plugs. Steady 35 mph or so in 4th/5th gear works well for me. You want minimal throttle so there's the least possible overlap effect from the cut-away or jet needle.
Setting the pilot circuit can take some patience as the screws are sensitive. Obviously, poor mileage, darker plugs are signs of richness. If the bike runs a bit more sluggishly at those lower rpms once hot/warmed up, that's another typical richness symptom. If a typical blip/rev of the throttle results in the rpms momentarily dropping below set idle, then returning to set idle, that's also a rich symptom.