SuperMoto Junkie banner

DRZ 400 Jet Kit question

34K views 40 replies 16 participants last post by  pbansen 
#1 ·
I'm looking at buying a new DRZ 400 and was looking online to see what would be the best jet kit to buy. The Yoshimura website says you only need to change out the main jet to a # 145, does this sound right? And if so how much should the jet kit cost me?
 
#29 ·
It does, but you shouldnt use screw adjustment as a substitute for the correct sized pilot jet. Your biggest indicator of an improper pilot jet is surging at cruising speeds, because you might still be able to get it to idle properly with the screw turned all the way out (or in), but thats not leaving any room for adjustment and doesnt solve the problem of surging in the lower throttle range.

I guess i shouldn't have said the pilot doesnt affect idle, because it does in a way. What i meant was the fuel screw only affects idle, so if idle is your only problem and it performs well everywhere else in the throttle range then you should adjust the fuel screw. However if you are having problems with getting it to idle, or you have to turn the screw all the way out (or in) to get it to idle, you are likely having problems elsewhere in the throttle range too. But just because you can get it to idle doesnt mean its right. Gotta check all ranges of throttle position.
 
#31 ·
hi i just got a new fmf power bomb down pipe and Remus Revolution Titanium Exhaust end can, K&N and R&G tail light can any one tell me what jet to fit and is there anything i need thanks wayne
 
#34 ·
What jet kit did you use? If you installed a full exhaust and did the 3x3 mod you will need a 25 pilot jet as well. The Dynojet kit doesn't come with it but the instructions should still say to get one and install it.

and for anyone else who bought a full exhaust and wants to do the 3x3 mod..just buy a jet kit. Its the easiest thing to do.
 
#37 ·
I have an 06 DRZ400SM and I'm doing similar mods...3x3...dynojet with 25 pilot jet, full Yoshi RS-2....

I live in Phoenix (sea level, warm, dry) and people are recommending:
160 main
dynojet 3rd or 4th clip
25 pilot
2-2.75 turns out

I should have it put together in a week. I'll post the results.
 
#39 ·
What clip position did you use, 3 or 4 from top?
 
#41 ·
Burned is the man...

By far the easiest thing to do is go to the Thumpertalk forum and search the DR-Z400 threads for jetting information from Eddie Cisneros, aka "Burned".

Burned is the DR-Z tuning/jetting guru and whatever combination of exhaust and elevation you're dealing with, he's answered the question at least once.

Regarding jetting kits: yes, you can just go to your local dirtbike or snowmobile shop and buy only the jets you need. The main reason that people buy the Dynojet or JD kit is that the kits come with a replacement needle that has a different taper than the stock unit. I live and ride at about 6,000 feet, so I changed the needle and the pilot jet only - the stock main jet was actually what Burned recommended for my elevation, although it would be wicked lean at sea level. This is with the 3x3 mod and the stock exhaust system.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top