Can't say enough how much I love my '07... mine was the smallest bike on our ride today, but she ran like a champ. MOSTLY. So I've done the usual mods, to include a 130 main and a new Two-Brothers slip on (along with N1Tc middle clip position, pollution stuff yanked, new snorkel, cut arrestor screen, crankcase breather re-route, K&N high flow etc) and she's still running LEAN. Lean like golden colored pipes and dry plug lean. Biggest issue for me is the still-every-so-often stumble while on throttle. No consistency here at all, but I will get random bumps in acceleration where the tach will drop down and she'll hesitate, then it's back to fine. Usually happens between 5-6/7k RPM... I'm stumped! Base elevation is 1200' and today we were as high as 4900'. So, bigger main? larger pilot? fuel mixture screw out more? ANY help will be greatly appreciated. It's a 5% problem that's giving me a 95%headache. Thanks in advance!! -- Lucky

 

Does it stumble in the same place when rolling on the throttle? What is your other jet size? stock?

I did a 128 main, but stock exhaust with holes drilled through the two plates. I noticed at higher elevations (4500+) she has poopy power. I usually do not ride that high, so I am not concerned.

 

That's the thing... the hiccups are pretty unpredictable! And when it happens it's only for a split second... no bogging or coughing... just enough bump to notice it. Always ON the throttle, never when off... usually during acceleration uphill or out of a turn... stock pilot jet... 130 main at the moment.

 

I take it the 130 Main is not from the DJ Jet kit because you mentioned the N1TC Needle. I also didn't see mention of doing the Carb Slide Mod.

Go 132 on the Main and do the Slide Mod and see what happens.

 

try moving the clip down one slot. That will raise the needle in the slide. at 5-7 k rpm's your on the main and the needle. a 130 main should be big enough even at your elevation so I'd try messing with the needle first. if that doesn't get rid of the stumble then go up one size on your mainjet. if you do have to go up on the mainjet put the needle clip back to where you had it. if the new main doesn't get rid of the stumble try moving the clip back to the lower slot to fatten up the mid even more.

 

i had a similar issue.. the bike was running lean.

 

Sorry Madark... I DID drill the slide 7/64. Didn't do the DJ kit... got all the parts from this forum and put it together... sounds like we have almost the same setup... +1 on motopro!!!

I will try the needle clip first and see... appreciate all the help.

Semper Fi!

 

JSAC, how did you remedy?

 

lcpl0331 has some very good advice on the needle clip. I suggested 1 higher on the main because you mentioned a moderately large variation in elevation in your original post. I think his post pretty much sums it up. Try the different clip position and, if it doesn't help, go up 1 on the main and drop your clip back down

 

that would be a question for the tech at the stealership.. i avoided issues and dropped a crisp 100 bill for a jet/dyno/jet to avoid problems like this :P