Anyone tried the JD kit for a 426 yet?

I to went to the Larryco Jetting and man did that ever make a diffrents. However if this is that much better than I am going to it. The only problem is, is that I missplaced my stock jetting and I mean all of it. I need to know what the stock MJ PJ MAJ MPJ where so that I can replace all of that. Any help??

42PJ, 75PAJ, DRR#3, 165MJ, 200MAJ. Not exactly sure about the needle, but the rest is stock (my '01 came with that DRR).


Did more testing today, ended up at signature jetting. Runs great, no issues. I get missing at WOT, tried MJ from 158 to 172. All jets the missing begins at 55 MPH in 3rd gear, stock sprockets. It has to be hitting the rev. limmiter. Never hit it before. Tried 158 and 172 MJ back to back, 55 MPH the missing starts. With the 165 the 1/4 to 3/4 throttle are better, also hits the limmiter very easily. I will start a new post to see if 55 MPH in 3rd is it. The difference between the 160 and 200 MAJ is so small that I can't decide. The 160 is in it now so I will leave it. You run the open pipe so a 168 MJ may be best. Think you will like it.


Thanks for the info. Cant wait to try it.

I'm using LarryCO jetting

38PJ 1.0 turns 65PAJ EKP#3 152MAJ (6K-10Kft) at 60-100 degrees

38PJ 1.5 turns 65PAJ EKP#4 155MAJ (6K-10Kft) at 30-60 degrees

I got so much more bottom end went to a 15 tooth front sprocket, still tractors like a John Deer and can do near 100mph in fifth gear. :)

JD are you saying that you switched to the James Dean jetting??? if so do you like it? I am working on switching to the James Dean set up from the Larryco. No Offence Larry, it is hard for me to understand that it could get any better than your set up but what the hell it is only money.

LOL No offence COULD be's all about getting your bike to run the way it was intended.

As a matter of fact, out of curiosity, I also procurred the JD triple taper needles to compare against what I'm running currently. If they run better than what I'm used to running (which I'm sure they will), then will I be switching? Heck yes! Faster...faster....aaaaggghhhh! :)



No I'm not switching. I've spent 2 months testing LarryCO setup with stock and I'm dailed-in. I did buy JD Jetting guide, which was a big help, but not the kit. I've decieded to spend the rest of the summer/fall riding :)

Went to the woods today, 55 miles of single track. The JD jetting is great. The big difference is approx. 1/4 throttle and up. Explosive power. I'm happy.

Got the jets in this weekend. Great performance. Much smoother on the road. A little jerky at certain RPM's but much better than anything else I tried. Well worth the money. Thanks JD :D



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