street driven 500 JETTING QUESTIONS

LAYNFRM · Post by **LAYNFRM** » May 5th, 2009, 9:52 am

i'll be running my GEN 3 500 on the street as a supermotard about 95% of the time, and the other 5% will probably be at a 1.8 mile roadcourse. anyone have any ideas on what i should start at? i really don't want to just give it a shot and end up with a hole in the piston. i'd rather foul a $13 plug than put a hole in the piston or seize the bike.

i am going to be running a pro circuit exhaust, V-Force 2 reed cage, and the stock carb. there is a good chance i will be 1/2-3/4 throttle the majority of the time on the street, with some random moments when i decide to gas on it all the way. i'm in louisiana, so it's generally fairly humid, and temperature is usually over 80 except during the "winter". elevation is around sea level.

i won't have but a week or less to get the bike tuned in before i leave for a trip to ride Deal's Gap in North Carolina at the end of the month

also, how much will i need to change my jetting for the trip to North Carolina?

fastkart · Post by **fastkart** » May 5th, 2009, 3:15 pm

LAYNFRM wrote:i'd rather foul a $13 plug than put a hole in the piston or seize the bike.

What are you running for a plug?? Here in Iowa, BR8EG's can be had for $16 for a box of 4.

LAYNFRM · Post by **LAYNFRM** » May 5th, 2009, 4:48 pm

NGK BR8ECM or BR8ECMIX. it's the short neck plug, and the second is the iridium version.

would moving to a BR9ECMIX add a little extra cushion when it comes to worrying about burning up a piston?

where exactly do i need to drill the holes in the wiseco piston, and how many? pics of said holes?

iggys-amsoil · Post by **iggys-amsoil** » May 5th, 2009, 6:37 pm

Personally I would use the same jetting I do for MX for the street Unless there's going to be a lot of WOT, then I would go up a size or two on the main. I would think the Humid would be about the same in either place and if NC isn't more than 2000' than LA should about the same.

I'd stay away from the colder plug.

Holes in the piston!?

I don't have them in the Wiseco I run.

LAYNFRM · Post by **LAYNFRM** » May 5th, 2009, 9:06 pm

i don't know exactly what the current jetting was setup for. he rode trails with it, but i don't know if he ran it rich or lean or what. i probobly won't be WOT much. i have to ride on a couple straight roads to get to anything decent or to town to hooligan it up, so i guess that would mean i'd need to run the pilot a little richer than stock?

the piston that was in it was fine. i think it was a wiseco. i might knock the carbon off the top and see if it has the same scribe marks as the new one i picked up today. i just had the cylinder honed and figured while it's apart i might as well throw a new piston in it since i don't want anything to go wrong a couple hours away from the house.

iggys-amsoil · Post by **iggys-amsoil** » May 5th, 2009, 9:52 pm

While carb is off find out what jets are in there, then compare that to stock jets.

LAYNFRM · Post by **LAYNFRM** » May 9th, 2009, 8:34 pm

iggys-amsoil wrote:While carb is off find out what jets are in there, then compare that to stock jets.

it's all stock jetting. 170 main

should i run a richer pilot and richer main?

100hp honda · Post by **100hp honda** » May 9th, 2009, 9:30 pm

unless you like pushing your bike home, i would stay away from #9 plug. they foul real easy in cr500 on gas, atleast the one i used did

LAYNFRM · Post by **LAYNFRM** » May 12th, 2009, 9:08 pm

just in case, i'm thinking i might throw a 178 or 180 main in it. i really don't want it to lean out and put a hole in the piston. anyone know what the stock pilot is so i can pick up one a little larger? the bike should be done by thursday night, so i need to get one asap.

iggys-amsoil · Post by **iggys-amsoil** » May 12th, 2009, 10:35 pm

Stock pilot is a 55.

Since its going to be street riden I wouldn't go any bigger than a 172 main. Most of the time it will be riden on the needle so I would consentrate on that. Umm scrach that, I see road course, so your looking at long periods of WOT?

32:1 premix
172-175
DGJ same as 1468
55

At best these are ball park, so I can't held responsible.

Jus sayin.

LAYNFRM · Post by **LAYNFRM** » May 13th, 2009, 3:04 am

i won't be hitting the road course but once or twice a year. i tried getting the needle out to check the clip position when i had the carb off, but i couldn't get the dang thing out.

what does DGJ mean?

Darrell262 · Post by **Darrell262** » May 26th, 2009, 7:11 am

I'd like to know how far off I am in jetting.

98 cr 500, stock carb. no motor work done pc pipe.
around 2000feet above sea level.

Running a br8es plug.

whatever the stock needle is in the 3rd clip pos and running a 175 main and a 65 pilot. 40-1 oil in it as well.

Plug color while held pinned for a long time is nice brown color to slightly darker.

I had to up the pilot 60 to keep it running when i let go of the gas. otherwise it would be 'dead' untill above 1/8th or so throttle.

I went to a 65 pilot and it idles nicely now and doesnt 'die' when I let go of the throttle.

a/s I think is around 1 1/2 or 1 3/4 out.

Should I try going smaller on my main jet?

Post by **AlisoBob** » May 26th, 2009, 7:25 am

Darrell262 wrote:
Should I try going smaller on my main jet?

Yup.....

Darrell262 · Post by **Darrell262** » May 26th, 2009, 4:19 pm

Forgot to mention the bike is .50 bored out with a wiseco piston.

BannedCR500Riders.com

street driven 500 JETTING QUESTIONS

street driven 500 JETTING QUESTIONS

Re: street driven 500 JETTING QUESTIONS