Author Topic: Main jet too big???? (Read 6677 times)

jshady77 · « **on:** September 22, 2015, 11:46:00 AM »

HEY ALL,

First off I want to thank all the great people on here for all the great advice, this is only my second R and am learning. I have a quick question, my new 86 R has 69mm piston, long rod, v force reeds, 38mm pwk 52slow and 180 main needle in 3rd position from bottom I believe, im in Michigan so 600-1000 sea level I believe, I know it is jetted rich for the fresh rebuild Im ready to rip on it, is 180 main too big, it just seems like I should be more around 165-175 mj I am going to do plug chop but already know Im very rich by the way she is running. Any help is appreciated.

Thank you,
Jeff

jshady77 · « **Reply #1 on:** September 22, 2015, 11:46:36 AM »

Sorry just checked spec sheet 69mm bore

Tbone07 · « **Reply #2 on:** September 22, 2015, 11:52:16 AM »

180 main sounds rich to me. Make sure you find out what needle you have, should be a 3 letter engraving (ex. DGH)

Pumashine · « **Reply #3 on:** September 22, 2015, 12:22:35 PM »

What pipe you running? I found big pipes want big jets. Stock replacements like FMF and DG use stock stock jetting. But on my Paul Turner race pipe I fried the piston with a 180 main.

jshady77 · « **Reply #4 on:** September 22, 2015, 12:47:26 PM »

stock needle, mid range pipe and fmf silencer

jshady77 · « **Reply #5 on:** September 22, 2015, 12:52:22 PM »

I say mid range pipe because It has no markings on it and the guy I got it from didn't know he bought it on ebay and was told its a mid range pipe

Pumashine · « **Reply #6 on:** September 22, 2015, 02:12:22 PM »

Air box lid on or off will also make a difference how the motor breathes

jshady77 · « **Reply #7 on:** September 22, 2015, 02:23:20 PM »

lid is on but has a small square hole cut into it??

jshady77 · « **Reply #8 on:** October 07, 2015, 09:50:37 AM »

Got this R running right now, changed out needle to a little leaner I believe its DEK, 178 main 52 slow needle clip 2nd from bottom airscrew 2 turns out, prolly could go a little leaner on pilot, but it is getting colder weather here in Michigan. Thanks for the help!!

Jeff

Rupp250 · « **Reply #9 on:** October 07, 2015, 12:17:58 PM »

Whats the plug look like?

jshady77 · « **Reply #10 on:** October 07, 2015, 12:31:04 PM »

It is a little rich after chop, when I put the 172 in it was whitish grey at bottom and brownish black on top, im thinking 175 may be sweet spot but I am staying a little rich because I am only about four hours on fresh rebuild, not to mention cold weather soon. What do you think??

jshady77 · « **Reply #11 on:** October 07, 2015, 12:31:50 PM »

Right now with the 178 it is black top to bottom

jshady77 · « **Reply #12 on:** October 17, 2015, 10:51:11 PM »

since the weather change in Michigan shes running top notch now with 48 slow and 178 main no changes necessary!!

swanitalia · « **Reply #13 on:** October 19, 2015, 09:54:45 AM »

Gotta love Michigan weather. Running a 60 pilot, custom needle 4th clip, and 230 main on my 268 stroker.

jshady77 · « **Reply #14 on:** October 19, 2015, 10:13:34 AM »

Yes for sure, after running yesterday in 40 degree, feels like I could come up more on jetting, seemed a bit lean. Mine is bored over 69mm with stroker kit so I believe Im at 284cc, are you in Michigan?