ATV Florida Forum

General => Tech Corner => Topic started by: coolcloo1019 on May 12, 2008, 12:55:50 PM



Title: Jet Size Chart
Post by: coolcloo1019 on May 12, 2008, 12:55:50 PM
Hey guys. I couldn't find any charts listed here so I did a little research and saw some information posted on another forum that I thought might be helpful for some of us. This is a chart showing the comparison between a Keihin , DynoJet and Mikuni jet sizes. Please don't be upset with me if you find out something different as I just took this from another forum.

Width------Keihin # -- DynoJets # -- Mikuni #
0.0350---- 92.5--------- 92----------- 86.3
0.0360---- 95----------- 94----------- 88.1
0.0370---- 97.5--------- 96----------- 90.0
0.0380---- 100---------- 98----------- 91.9
0.0390---- 102.5------- 100---------- 93.8
0.0400---- 105--------- 102---------- 95.6
0.0410---- 107.5------- 104---------- 97.5
0.0420---- 110--------- 106---------- 99.4
0.0430---- 112.5------- 108--------- 101.3
0.0440---- 115--------- 110--------- 103.1
0.0450---- 117.5------- 112--------- 105.0
0.0460---- 120--------- 114--------- 106.9
0.0470---- 122.5------- 116--------- 108.8
0.0480---- 125--------- 118--------- 110.6
0.0490---- 127.5------- 120--------- 112.5
0.0500---- 130--------- 122--------- 114.4
0.0510---- 132.5------- 124--------- 116.3
0.0520---- 135--------- 126--------- 118.1
0.0530---- 137.5------- 128--------- 120.0
0.0540---- 140--------- 130--------- 121.9
0.0550---- 142.5------- 132--------- 123.8
0.0560---- 145--------- 134--------- 125.6
0.0570---- 147.5------- 136--------- 127.5
0.0580---- 150--------- 138--------- 129.4
0.0590---- 152.5------- 140--------- 131.3
0.0600---- 155--------- 142--------- 133.1
0.0610---- 157.5------- 144--------- 135.0
0.0620---- 160--------- 146--------- 136.9
0.0630---- 162.5------- 148--------- 138.8
0.0640---- 165--------- 150--------- 140.6
0.0650---- 167.5------- 152--------- 142.5
0.0660---- 170--------- 154--------- 144.4
0.0670---- 172.5------- 156--------- 146.3
0.0680---- 175--------- 158--------- 148.1
0.0690---- 177.5------- 160--------- 150.0
0.0700---- 180--------- 162--------- 151.9
0.0710---- 182.5------- 164--------- 153.8
0.0720---- 185--------- 166--------- 155.6
0.0730---- 187.5------- 168--------- 157.5
0.0740---- 190--------- 170--------- 159.4
0.0750---- 192.5------- 172--------- 161.3
0.0760---- 195--------- 174--------- 163.1
0.0770---- 197.5------- 176--------- 165.0
0.0780---- 200--------- 178--------- 166.9
0.0790---- 202.5------- 180--------- 168.8
0.0800---- 205--------- 182--------- 170.6
0.0810---- 207.5------- 184--------- 172.5
0.0820---- 210--------- 186--------- 174.4
0.0830---- 212.5------- 188--------- 176.3
0.0840---- 215--------- 190--------- 178.1
0.0850---- 217.5------- 192--------- 180.0
0.0860---- 220--------- 194--------- 181.9
0.0870---- 222.5------- 196--------- 183.7
0.0880---- 225--------- 198--------- 185.6
0.0890---- 227.5------- 200--------- 187.5

And this is from DynoJet...

Quote
We are often asked for a "cross reference" sheet that compares our main jets to Mikuni or Keihin. The fact is you cannot directly interchange the jets for a given size. Many things affect fuel flow through a jet of the same orifice size. The entry and exit tapers of our main jets differ from those of other companies. Due to this, the fuel flow changes as a function of velocity through the carburetor venture. This means that two jets of equal orifice size will have a different fuel flow curve relative to intake air speed. At a certain speed the two may flow equally, but a change in velocity changes the flow characteristics. The Dynojet main jet hole size is measured in millimeters. For example, a DJ142 has a 1.42mm hole.


Michael Cory
Research & Development
Phone: 800-992-4993 EXT. xxx
Michael@Dynojet.com


Title: Re: Jet Size Chart
Post by: Chevy1500z71 on May 12, 2008, 01:02:56 PM
i feel left out, im running a 320 main in my rotax and that chart only goes to 200...


Title: Re: Jet Size Chart
Post by: coolcloo1019 on May 12, 2008, 01:09:59 PM
i feel left out, im running a 320 main in my rotax and that chart only goes to 200...

Sorry bud. lol.


Title: Re: Jet Size Chart
Post by: TRX450R_Racer on May 12, 2008, 01:37:43 PM
That's good info.

Thanks.


Title: Re: Jet Size Chart
Post by: mrbones on May 12, 2008, 01:54:21 PM
FYI on Keihin.

Keihin jets are sized in mm. So a 100 is a 1mm hole. 150 is a 1.5mm and so on. So, if you have the appropriate drills, you can drill them larger.


Title: Re: Jet Size Chart
Post by: Chevy1500z71 on May 12, 2008, 09:16:56 PM
FYI on Keihin.

Keihin jets are sized in mm. So a 100 is a 1mm hole. 150 is a 1.5mm and so on. So, if you have the appropriate drills, you can drill them larger.

i think iv tryed drilling a 70 main jet out on a moped... the results were not very impressive lol it looked like about a 500 when we were done with it and the moped ran ok... kinda