So today I took my track bike into PJ's Motorcycles to get a baseline done on the dyno. I am running very rich, and I have that nasty dip at 5k.

I'm running 118 front 120 rear on the mains, 35 pilot all around, 4 hole emulsion tubes front and 5 hole rear, stock airbox with K&N element, and an aftermarket exhaust. I also looked at the needles and I'm running something aftermarket. It is the gold one in pic set at the third position. I also have a set of the silver needles in the pic, but I'm thinking that with the bike running as rich as it is, maybe I don't want to put those in just yet. I'd like to get the fueling spot on, then later on put the HRC setup in from Rick O and see what difference it makes.

Anyways, on to the pics of the needles and dyno sheets...








Also, WTF is happening at the top end of the rev range?

i reckon you have a issue with missfiring at the high RPM

bad plugs or something else

Those plugs are pretty new...but with it running that rich they are probably fouled.

Does it burn oil, what was the altitude, temperature and humidity, do you have a strong spark, were the carbs cleaned, float levels set and float needle valves checked?

Other than that it's probably a good idea to get a set of road needles from rick and start with those and standard sized jets.

I forgot the pilot screw check.

IMHO a needle change would not make much difference, the top end mixture is a main jet function. Restrictive air filter will cause over-rich mixture that could be significant at the top end of the rpm range, are K&N filters as good as OEM (you can get OEM filters from PowerSportsPlus, bought two last week). May be remove the K&N filter and see if the mixture become leaner, might still not be perfect but could head you in the right direction.

magg wrote:IMHO a needle change would not make much difference, the top end mixture is a main jet function. Restrictive air filter will cause over-rich mixture that could be significant at the top end of the rpm range, are K&N filters as good as OEM (you can get OEM filters from PowerSportsPlus, bought two last week). May be remove the K&N filter and see if the mixture become leaner, might still not be perfect but could head you in the right direction.

Those needles look like factory pro ones

krisztian_andre wrote:Does it burn oil, what was the altitude, temperature and humidity, do you have a strong spark, were the carbs cleaned, float levels set and float needle valves checked?

Other than that it's probably a good idea to get a set of road needles from rick and start with those and standard sized jets.

I forgot the pilot screw check.

Doesn't burn oil, altitude is 5300 feet ASL, temp was 71 F (21.6 C), 13% humidity. Spark should be strong, but with the bike running that rich, the plugs may be F-ed. Carbs were clean, floats were a touch high...maybe 7-8mm instead of 6.8mm, float needles were good, and pilot screws set properly.

I know this doesn't do anything for fuel metering, but I think the hole in the slides is still std. What diameter do we drill those out to again?

I'd try n put it back to standard jetting and see what happens, i wouldnt of thought the filter would make it go rich.
Cheers
Ian

It IS set to standard jetting!