Jet kits vs just jets

I have a 2002 S model and want to do the air box, jet mods and drill out the exhaust. (exhaust insert done, what is done is done).

The air box seems pretty straight forward, just don't go too deep.

My question is; why a dyno jet kit at $85 canadian when a couple of jets (150 main ,27.5 pilot) would seem to do? Is the Dynojet #3109 jet kit magic. I feel fairly confident around my bike until the word "carb" is spoken or I go near it. Thanks a lot for any input.

the jets will get you by.the dynojet kit is "magic"!any body here that has one will just depends on you want.runs ok or pefect. :)

I have used both, I bought the jets, and opened up the airbox and rode the bike for 1 day and wasnt very happy with the throttle response. The next day I ordered the Dynojet kit, put it in, dialed it in, and the bike ripped I dont think the stock carb could get any better. In my opinion the only two options I would consider would be either the Dynojet kit, or an FCR carb.

Besides the main jet and a pilot, what else does the dynojet kit include? It must have a needle and clip also.

You basically buy the kit for the needle. It comes with a bunch of main jets, but if you have your airbox cut out they will all be too lean. Right now I have a 145 main jet, 25 pilot, dynojet needle in the 4th clip, and the fuelscrew 4 turns out. That is with a full Yoshimura exhaust. With the stock exhaust I had the same set up with the exception of a 140 main jet.

interesting Mike.... ive got the same bike you do with the same setup as you and my jetting is a bit different that yours. im running a 150 main and a 25 pilot with the dynojet needle in the 3rd clip. does that seem a bit rich? i couldnt be any happier with the bike though as it rips hard thru every gear. but yeah, youre pretty much just spending 60 bux or so for a little needle and some springs that you dont need to replace. and the kit comes with a couple of stickers and we all know that stickers make your bike go faster! :)

Fastmike, looks like you can go leaner on the main and pilot with the dynojet needled though. Most guys are running 27.5 pilot / 150 main with airbox mods and pipes (or just airbox mods). Is the needle a richer taper than the stocker? Maybe we can run a richer needle and save some cash over the dynojet kit. Although I don't recall how much needles are.

Every thing I have learned about the dynojet setup has been from Burned, he is pretty knowledgable with the dynojet stuff. With the stock needle you have to go overly rich on the main, and pilot jets to compensate for the lean needle, with the dynojet needle you can get away with a leaner pilot, and main jet

Sparky, I have the middle T.E.C. insert in with my Yosh pipe, and just went to the 145 main, I could probably go richer on the main but it works weel as is. I had a 142.5 main and when I went with the 145 main There wasnt much of a difference.

Did I jump the gun? I went and ordered the Stage 1 Dynojet kit and the largest number on the jets supplied is "DJ136".

I see that the DRZ comes stock with a 142 main jet. Did I just spend $85 to run a Stage 1 engine too lean?

It would seem to me that Dynojet must know a thing or two about carburetor jetting. Maybe the DJ136 isn't actually a "136" (seems to me it would be).

Should I cancel my order or trust Dynojet to do it right?

Thanks for your help, I don't want to burn up my bike (800km).

The dynojet kit is made to work with the stock airbox, if you havent cut the 3"x3" hole in the top of your airbox it will probably be OK, but you should do the airbox mod, and run the stock main, with a 25 pilot. I ran this at sea level with the stock exhaust and my bike ripped.

Dynojet jets numbering dont usally run the same as your stock jets they use there own #

fastmike has covered it really well!as far as the numbering system ive measured the dj jets and mikuni jets and the are virtually identical in numbering.a 142.5 mikuni is the same as a 142 dj.the bigger jets are shearly becuase of the air box mods.get the dj kit and never look back. :)

I typically ride at 3k to 5k altitude. Can anyone tell me how these combinations of needle, main and pilot jets work at these elevations? I'm using the stock pipe for now. I will be doing the airbox mod and will be using the No Toil filter.

This sets the record straight on dynojet kits.,

Sent from the Internet (Details)

Dynojet main jet sizes and stock main jet sizes bear absolutely no relationship to one another and cannot be compared to each other. Dynojet main jets are designed differently than stock jets (the human eye cannot see the differences) and are designed to flow fuel properly for their jet kits.

Japanese bikes typically come stock with overly rich carburetion up top, i.e. the stock main jet is too large. They are also typically too lean down low. This is why Dynojet jet kits work; they are designed to correct the stock jetting faults.

As per the instructions, Dynojet jet kits are designed to work with “mildly tuned machines using the stock airbox, with stock or K&N filter. May also be used with a good aftermarket exhaust system.” If you make the modifications to the airbox you mention, more than likely the Dynojet kit will not work properly. If you use the Dynojet kit you must work within the design parameters of the kit, as noted, i.e. an unmodified airbox.

Personally, I would not make the airbox modifications unless you know someone who has already done it and has his/her bike running CORRECTLY and who can give you EXACT carburetion setup.

Either use the Dynojet kit within its design parameters or don’t purchase it.

Good luck.


Steven Brendle

Product Manager

PH: (403) 219-8768

FX: (403) 250-7984


Parts Canada/Power Twins

"We support the Sport"

Email Burned. I bought the DJ Kit, and he set me straight on a good baseline for installing it with my 3X3 airbox mod. Stuff like this is why Thumper Talk is great.

never mind,i have no idea what im talking about.its shear luck anybodys dynojet kit is working.disregard the 5 yaers i spent developing dynojets high altitude kits let alone the thoudans of hours ive spent in the dyno room!

I agree that Burned is the man when it comes to Dynojet kits :) PS I sent the Forks out yesterday with a check Eddie. If the amount comes out to more than the check is let me know, and I will overnight you the difference. Thanks dude.

cool mike!i will do them up and fire back at you!of course i will move you to the front beacuase your a tt'er! :)

Burned, then here's what I want to do. Stock DRZ-S, stock pipe, want the 3x3 airbox mod, want to keep the stock pipe. Live in Michigan, 0-1000 ft. altitude, what should I use for jets? Which kit and / or which jet numbers? Thanks man I appreciate it.

Didn't mean to discredit anyone.

Just passing on the information that the company sent me.

I know I like to have facts before buying a product, and the DRZ is such a great bike that you have to know you are making it BETTER. It's good to listen to all sources.

I think it would be a great idea to have a modifications database or spreadsheet that everyone can look at for good "go-byes".

Everyone loves modifying there bikes, very expensive but fun.

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