DJ conversion chart, how accurate?

[ManicHaze]

I would normally try using keihin jets but I already have this old DJ jet kit. I'm not gonna run the 12 hole mod for the time being, and just want to get back jetted a couple numbers above stock because of my Aliens.

The issue here is, I looked at the stock 140 compared to the DJ 126 (according to the chart, they are the same, or close) and the hole in the keihin is obviously larger. I dont know much about jet design, but it seems to me the hole should be the same size to equal the same jet number...correct? Or does the inner taper effect the overall jet size? Or do you have to use the DJ needles ( <_< ) to equal the keihin size?

thanks for your help guys

p.s. this is with STOCK NEEDLES

edit: I just compared the largest in the kit, which is a 138 to the keihin 140 and they are damn close to the same hole size...am I missing something?

[flipper]

Don't do it! Use the Keihn ,and their needles as well. DJ are all over the board in that they have same size in numbers. But the opening size in different from what they claim. Too many knock offs, you never know what, and who you really are getting it from. You may get lucky and have no problems with them. But, then again you might not. It's a crap shoot. Stick with what has been proven to work, and that others can help you on with answering questions. With DJ you can get little help because other than fewer people using them, they are inconsistent on top of it.

[ManicHaze]

I know I know, I wish I had the keihin jets but I have had these lying aroud and I need to jet close to stock so I figure I could get away with using the DJ with the stock needles.

[Camo]

You can use the DJ jets with stock needles with no problem at all. Use the conversion chart and jet accordingly. That's all I've used (with the DJ needles) and my quad runs primo. Most will say not to use the needles. Don't use them then, but don't fear that the mains are going to mess you up. They are just a different number like some drill bit sizes.

How are you comparing hole size? Unless you are using a small, precise instrument...it's not accurate enough to tell.

[Bigun]

Quote:

You can use the DJ jets with stock needles with no problem at all. Use the conversion chart and jet accordingly. That's all I've used (with the DJ needles) and my quad runs primo. Most will say not to use the needles. Don't use them then, but don't fear that the mains are going to mess you up. They are just a different number like some drill bit sizes.

How are you comparing hole size? Unless you are using a small, precise instrument...it's not accurate enough to tell.
[/b]

I use the DJ jets and also question the conversion chart. I'm jetted 170f-175r according to the chart it would be 184f-189r on the Keihn scale It should be quite rich but runs strong all the way through the powerband. 12 hole mod, twin air filter & cage, shortened carb springs and polished slides, shimmed needles and Muzzy pipes. No internal mods. The quad pulls strong but I still can not get rid of a deceleration pop. Elevation is less than 500' above sea level.

[flipper]

Hey ManicHaze What sizes would you think you'd be needin'? I have a few kickin' around and I just got a new pair of readin' glasses. It'd take me no time to check and SEE if I had 'em and mail 'em to ya. NO CHARGE!...Just send back all but the two you don't use, There fellow kawierider. Hey it's worth a shot!

[ManicHaze]

Thanks for the offer flipper, I might have to take you up on it. I did some more testing today and I gotta be close on my jetting. No pops on decell, and it seems to pull good. I cant get a good plug reading because I'm in my neighborhood and my neighbors already think I'm too loud because of my TransAm with open exhaust... dont need to give them more excuses. Hopefully I can get some better testing in this weekend and get a good long full throttle run to check the plugs with.

Camo, I'm using the DJ needle to test the sizes. it fits snug into the DJ 126 but doesnt fit snug at all in the Keihin 140 which should be the same size according to the chart. The 140 Keihin is closer to a 136 DJ or so if you go by hole size alone. This is why i'm confused!!

oh yeah, I ended up using a 126/128 DJ with the stock needles. I dont have the 12 hole mod, but I do have a K&N and dmc aliens. So far, no popping on decell or accell....but like I said, I can't go full throttle for more than couple seconds. Seems to run healthy!

[flipper]

Hey I misunderstood you on the sizes. You ARE NOT currently running the 12 holes. Thats cool too I can still help if you need it. It would only take one extra day though those smaller ones are not at my home, they are at our repair/storage shop that I share with a couple snowmobiling, and wheeling buddies. But, the offer still holds firm. Just let me know.

[Bigun]

Quote:

Hey I misunderstood you on the sizes. You ARE NOT currently running the 12 holes. Thats cool too I can still help if you need it. It would only take one extra day though those smaller ones are not at my home, they are at our repair/storage shop that I share with a couple snowmobiling, and wheeling buddies. But, the offer still holds firm. Just let me know.
[/b]

Try 138f 140r to start with.

[ManicHaze]

because of my elavation (just above sea level, about 300) I am gonna go a little richer, about 140/145 or so. I have the baffle trimmed almost all the way down, and the K&N. When I added the K&N i did a plug check (this was with stock exhaust, a couple years ago) and if I remember correctly I was not as rich as id like, more towards lean. 140/145 should be a good hit. Id raher be slightly rich if anything. If i am a tad rich in the summer, that gives me overhead should I ride on a cool night or in the winter.

flipper, thanks again man. I will let you know either tonight or tomorrow if I need those jets. If you have the jets I'll need for the 12 hole mod, I might just go ahead and do that and just worry about dialing it in once...at least I could avoid some of this head ache by only having to jet once!