Previous owner jetting!

[skirecs]

Bought a 07 with 3600 miles on, now has 5000 and decided to do daves mod

im at 300-1000 feet

Before: FMF exhaust, powerbomb header, uni air filter

jetted 50, 165, needle second clip down

I got 55, 160 and pulled the snorkel, and left the needle as is because i didn't know how it correlated to shims etc

Any suggestions on needle position?

results:

I started playing with the mix, and at around 2 turns it seemed to have the highest idle, but when I cracked the throttle really quickly it might have pinged

i never have heard a ping first person, sounds sorta like someone tapping the back of a tablespoon on the head, is that it?

so i richened the mix a little and turned up the idle a hair and it seems to be better, still hard throttle at low rpm there is a stumble, maybe for one rotation, then it picks up and seems to have more power, lifts the front a little easier

from 75-100% throttle there seems to be no difference in the pull, is that normal?

thanks fellas, im just not used to this carb yet and the signals its telling me

[bronnco79]

Hi comp piston in it? U check valve clearance

[HeadTrauma]

needle second clip down

Does the needle have a selection of grooves in it? If it does, it's not original and there's a good chance it came out of a Dynojet kit. There is likewise a possibility that the slide spring is from the same DJ kit, so you can skip drilling the carb's slide. The jets you picked sound about right. As for pinging, what fuel grade is it getting? What does the spark plug look like? Pinging is one of the most difficult sounds to describe and hearing it in a video doesn't do the actual sound any justice. You just about need to have someone present that knows how to point it out as it happens.

[skirecs]

Well shit, I've drilled the holes to 5/32

It seems to run at 65 mph with less throttle than before, but that was only with a little testing

I think ill try a little richer on the idle mix, but there still is that slight hesitation when I hit the throttle hard from real low rpms, maybe that is just a shortcoming of the CV

It was pissing rain all day, perhaps tomorrow I'll ride a tank and get some more info to tell you

thanks all

[bronnco79]

U check for air leaks? Wouldn't explain the noise tho...

[skirecs]

Just out riding before it started hailing on me...

There is a little stumble from low rpm that I can't seem to get rid of with the mixture, is that because the slide is all messed up from the combination of drilling and aftermarket spring?

Also, coming down from high revs like cruising at 50 then to a stoplight it has a little trouble with idling before steadying out, previously it would come right down and be steady, whats that a symptom of?

[zx12r]

Just out riding before it started hailing on me...

There is a little stumble from low rpm that I can't seem to get rid of with the mixture, is that because the slide is all messed up from the combination of drilling and aftermarket spring?

Also, coming down from high revs like cruising at 50 then to a stoplight it has a little trouble with idling before steadying out, previously it would come right down and be steady, whats that a symptom of?

If you hit the gas from idle and the rpm's hang up a little before settling in, its lean. If it goes below idle rpm's then goes back up its rich.

[skirecs]

OK, I think I'll pop the DJ165 back in to see if that helps the top end because its feeling pretty weak

25-75 % right now is pretty strong and good response so im thinking needle and slide are OK

The only other thing is coming down from high speed and braking to a stop sometimes lets it stall. Is that to rich or lean on the mixture screw?

Before was a 50S, put in a 55

[jjast]

probably rich, mine would do that with a 58 pilot and when I went to a 55 it cleaned it right up.

[skirecs]

probably rich, mine would do that with a 58 pilot and when I went to a 55 it cleaned it right up.

hmm ill try leaning it out with the mix a little more, i thought surely 55 would be spot on based on others remarks especially at sea level, snorkel removed etc etc

is there an equivalent size to a DJ 50S that was in it previously?

[skirecs]

i put the DJ165 back in, seems to help the top end a little bit over the 160

DJ needle and spring AND drilled, midrange seems fine, so no problems

i have the mix quite lean at a little less than 2 turns with a 55

any richer and it likes to die when slowing to a stop at a light or something

my feeling is that this is still much richer than stock so it won't do any harm, is that correct?

[jjast]

If you have your fuel screw at a little less then 2 turns out then that's set pretty good, you might even want to try a bit leaner on the fuel screw If it's a bit hard starting when it's warmed up.

[skirecs]

thanks all, ill lean it a bit and it should be great