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Pete in PA
Im going to order some jets from The 2006 Chaparral catalog page 507.

When the # gets bigger, does the hole get bigger or smaller?

Is it the same for main and slow jets?

I know the current main #'s are 140 for cylinders 1 & 4 and 142 for cylinders 2 & 3. (why, I don't know, it's liquid cooled) I want to go to the bigger of the #'s for all cylinders.

The slow jets are #42. I want to go up one size since I'm at 3.5 turns out and that's too much. Once you're past 3 turns out you go up a size.
bartonmd
correct... the bigger the number, the larger the size...

I'm the same on pilot jets, so let me know how it works out for you...

When I did the Factory jet kit, it said to just put 142's all the way across for the way I'm set up...

Mike
airborneXX
+1 on larger # = larger hole.


While we're on the topic of jets, does anyone know the cross reference from Dynojet's numbers to stock Keihin #'s?

Example: I have Dynojet 140 mains, what is that equivalent to in a Keihin jet.
CALCXX
Rich, I'm running the 145's. Akra pipe. Showed 14/1 AF on dyno. Could go richer. I'm @ an altitude of 410 feet. I left it a little on the lean side cause I usually ride @ higher altitude. Runs good!
Pete in PA
icon_cool.gif , Thanks guys. I'll order today.
jrex
QUOTE(airborneXX @ Sep 26 2006, 12:02 PM) *

+1 on larger # = larger hole.


While we're on the topic of jets, does anyone know the cross reference from Dynojet's numbers to stock Keihin #'s?

Example: I have Dynojet 140 mains, what is that equivalent to in a Keihin jet.


Taken from the Mechanical Archives section at quadzone.com:



Dynojet...Keihn...Mikuni.... Jetting chart

--------------------------------------------------------------------------------

Width------Kehein # -- 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
airborneXX
Thanks for the chart!
Pete in PA
Well I installed 2 #142 mains (so now all 4 are 142's) Went to #45 pilot jets with pilot screws out 2.5 turns and added washers to my needles for a total with the stock washers of 45 thousanths. runs awesome!

Since I drilled out my stock pipes it wasn't quite right.

Now even with 1 tooth up on the front (18 tooth) it's trying to power wheelie in 2nd gear! The front tire is just skimming the pavement and if it hits a slight bump it leaves.
blackhawkxx
QUOTE
The front tire is just skimming the pavement and if it hits a slight bump it leaves.

Complete highjack
Did you watch the Pro Stock bikes at Reading last weekend? Hines went through the lights at about 190 mph and his front wheel was so high off the ground that it was on the wheelie bars. They said there is a sight bump right before the finish line. It was wild.
Pete in PA
QUOTE(blackhawkxx @ Oct 3 2006, 08:27 AM) *

QUOTE
The front tire is just skimming the pavement and if it hits a slight bump it leaves.

Complete highjack
Did you watch the Pro Stock bikes at Reading last weekend? Hines went through the lights at about 190 mph and his front wheel was so high off the ground that it was on the wheelie bars. They said there is a sight bump right before the finish line. It was wild.


Nope didn't even know about it. let me know when anything like that happens locally. icon_frown.gif

I did go to 2 soccer games my girls were in and went fishing over the weekend. Caught 1 trout, 4 bass, several bluegill, and one tree icon_evil.gif . My oldest caught the first fish of the day but my bass was the biggest. eusa_dance.gif

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