Starved?

[Steve]

If your petcock is flowing enough on PRI to keep the bike running, it should be obvious that the petcock is not limiting your fuel flow.

My opinion? (Well, you asked.) Back off the throttle just a little. With your pods, there is not enough vacuum to keep the petcock open at wide open throttle. Back off to about 3/4 throttle to see if that helps.

Not sure if you might have a small leak in the petcock diaphragm (that would show up as fouled plugs in #2 cylinder), but just about any vacuum-operated petcock you put in there will do the same thing. If backing off the throttle a bit does not help, you will have to change to a manually-operated petcock. (Did I hear somebody say "Pingel"? )

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[chef1366]

Ah ok, well I think I did that. I just copied the picture. Haha. I also get confused with what's "above" and "below". Regardless, I doubt a millimeter change in the needle height is causing my problems. It's definitely a major fuel starvation issue.

Believe it or not it probably does make a difference.

[jonmasaya]

If your petcock is flowing enough on PRI to keep the bike running, it should be obvious that the petcock is not limiting your fuel flow.

My opinion? (Well, you asked.) Back off the throttle just a little. With your pods, there is not enough vacuum to keep the petcock open at wide open throttle. Back off to about 3/4 throttle to see if that helps.

Not sure if you might have a small leak in the petcock diaphragm (that would show up as fouled plugs in #2 cylinder), but just about any vacuum-operated petcock you put in there will do the same thing. If backing off the throttle a bit does not help, you will have to change to a manually-operated petcock. (Did I hear somebody say "Pingel"? )

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Hmmm. Well, it definitely ran worse on PRI, it was just the only option to get home without pulling over every few miles. The issue only comes up at 60mph+. I never had the throttle pulled all the way back... Not sure how to explain this, but I could kind of find a sweet spot. Too much throttle and you get a resonant sound and no power.

I should also mention that the switch on my petcock is ridiculously hard to move, often requiring a wrench. I'm thinking its time has come either way. Is the non-vacuum petcock really the way to go? I've ridden hondas for a while and I always forget that damn thing. ("WTF! I can't be out of gas already!")

[Steve]

When you installed your Dynojet kit, did you also drill the slides?

DJ includes a drill to enlarge the vacuum port on the bottom of the slides to enhance operation with limited vacuum.
If you have not yet drilled the slides, that might be (at least part of) your problem.

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[jonmasaya]

When you installed your Dynojet kit, did you also drill the slides?

DJ includes a drill to enlarge the vacuum port on the bottom of the slides to enhance operation with limited vacuum.
If you have not yet drilled the slides, that might be (at least part of) your problem.

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Yup! Drilling those out was the scariest part.
I followed those instructions to a T.

[gearhead13]

I really dont think a pingel is needed here, I have the stock petcock on a built 750 with 34mm mikunis and have no problems, maybe when i stuff the 1100 in I could have problems, but I *think* the 1100 and 750 petcocks are the same, arent they?

[almarconi]

Did you check for air leaks?

Sounds like its running lean on the mains. Did you check your fuel height (in the carb bowls)? It's possible your fuel height is too low.

What do your plugs look like?

[KitKat]

i had this same problem when i bought my bike. it would accelerate up to a point, then it wouldn't around a certain speed.

i replaced the petcock with OEM
cleaned carbs
... almost everything mechanical

what it turned out to be was the r/r. Mine did something funky: when it wouldn't further accelerate, i turned a turnsignal on, and the engine would suddenly pulse with immense power at the time the signal was flashing. so then i took out one turn signal bulb: which makes the turn signals stay on constantly, which gave me constant power throughout. Also had a similar effect when using high beam.

got a honda r/r from duanage and now perfect. might want to test your r/r

[gearhead13]

did you clean (dip) the carbs and put new o-rings in them when you put in the dj kit?
Take a look at your plugs, take a pic and/or note different colors, especially #2.
I noticed that those arent K&N pods, the dj kit is tuned for K&N pods AFAIK. You might need a richer or leaner main.

[GavinJuice]

at 60MPH he's barely running on any main jet, this is all needle and pilot in play here and further there is no mention of any WOT where main is found.

on a VV carb you could easily choke it to see if you're rich or lean at the speed you talk about, but a CV i don't know if there's enough signal for the fuel enrichment?

[jonmasaya]

Carbs were cleaned immaculately by the P.O. O-Rings were in pretty good shape. Choke had little to no effect at 60mph, but will try again.

I ordered a new petcock. In the meantime I'll take the carbs back apart and check everything, along with the plugs. I might try a different needle position as well.

Thanks everyone for your help so far!

[jonmasaya]

Update: Installed new petcock. It definitely fixed part of the problem, it no longer starves out and runs quite a bit smoother. However, it still stumbles and hesitates a bit at high speed. I just noticed that the Mac exhausts have a similar back pressure to stock, so I'm probably running too rich with the 130 mains. I'm going to switch to the 124s and see if that helps.

[chef1366]

Update: Installed new petcock. It definitely fixed part of the problem, it no longer starves out and runs quite a bit smoother. However, it still stumbles and hesitates a bit at high speed. I just noticed that the Mac exhausts have a similar back pressure to stock, so I'm probably running too rich with the 130 mains. I'm going to switch to the 124s and see if that helps.

Check the spark plugs. Reading them will tell you if you are rich.

[Steve]

I just noticed that the Mac exhausts have a similar back pressure to stock, ...

Please tell me: how are you measuring the backpressure?

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[chef1366]

Please tell me: how are you measuring the backpressure?

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He puts his hand over the can?