FCR tuning

[terse750]

Glad you didnt hole/melt a piston.
Based on Speeddogs jetting (iirc) and since you have pods, try needle posn 4 or 5 and 160 main jets and see what the plugs say about it. Thats based on the assumption the plug porcelain is white all the way down to the base of the plug and it was a high speed plug chop. Are there coloured bands on the porcelain as you look down into the plug?
Some lift the needle until they get the roll on power at its best and then do a plug chop at half throttle to ensure its not too rich at cruising speeds. You can tune for slightly lean cruise and let the accelerator pumps help when you whack open the throttle.
What kind of pods are they?

The plugs looked slightly ashy(dry), black threads, and a light brown ring around the bottom of the white porcelain.
Now keep in mind I had the plug gap at 4.5 now trying 5.5 as soon as I get the pump in order. Tried to go 6.5 then 6 and didn't want to start...hissing and puffing with a few CRACKS!!!! Sounds rich in the start for sure, a? Got her firing nicely with 5.5 gap. (just idled today)

The pods are a "UNI" 2 stage angled pod mesh, oiled and covered with a k&n blue dry charge wrap.

Today when I opened the shed it smelled like gas, pulled the bike out and she seems to be weeping or leaking around the fuel pump.
Didn't have much time to do anymore digging, so I'll have to inspect more asap.

Whats this about an accelerator pump?

[koko64]

0 of ours is my limit, but my hands hurt for a week last time I did it.

[ducpainter]

It really isn't fun at 8.

[koko64]

Your tuning data could be ruined by that pump leak. Fix it first before any more tuning.

A light brown ring at the base of the porcelain aint too bad, but get it brown for WOT with a jet or two after you test with a repaired pump. One step richer than ideal is the drag racers practice.

Consider the jetting base settings I have guessed based on speeddogs setting for stock airbox sans snorkels (once that pump is sorted). Eliminate any white porcelain bands.

FCRs have little water pistol type fuel squirter jiggers that add extra fuel when you crank the throttle. They let you run cruising mixture a little on the lean side of good for excellent economy and smoothness. My FCRs gave getter mileage than stock carbs by 20-30 miles a tank!

[Speeddog]

If you keep changing the plug gap while you're chasing carb settings, you'll be lost for a very long time.

My recommendation is to set the plug gap to 0.023"-0.027", which is the OEM spec, and quit dicking around with that.

Change only one thing at a time, then you've got a chance of figuring out what that change actually accomplished.

[Speeddog]

~~~SNIP~~

While we're on the subject of stock vs flatslides, I miss my choke already and it isn't even cold.

Try closing the air screws in the bellmouth 1/8 turn, see if that helps.

I'm pretty well convinced that the CV Mikunis can compensate for air density (pressure/temperature) pretty effectively.
The FCR's, eh, not so much.

With the FCR's on my M750 I noticed a difference in running quality with a drop of 600 feet of altitude and 20 degF on my previous commute home from the shop.

[koko64]

Listen to this guy.

[terse750]

If you keep changing the plug gap while you're chasing carb settings, you'll be lost for a very long time.

My recommendation is to set the plug gap to 0.023"-0.027", which is the OEM spec, and quit dicking around with that.

Change only one thing at a time, then you've got a chance of figuring out what that change actually accomplished.

I hear you! I thought plug gap was supposed to be .065. From ducati suite site and I thought I read it elsewhere.
But, after hearing .023... ok ok no problem there. I always thought she cranks much easier with a smaller gap than 0.060. lol

First things first fuel pump will need repair.
Plug gap will be at 0.025.
Thanks guys

[koko64]

mm or thou?
In decimal it's 0.6mm on regular plugs or 0.9mm on Iridiums (if you got strong coils).

Dammit, they changed from Imperial to decimal half way through school when I was a kid.

[Howie]

mm or thou?
In decimal it's 0.6mm on regular plugs or 0.9mm on Iridiums (if you got strong coils).

Dammit, they changed from Imperial to decimal half way through school when I was a kid.

Ding ding.  Maybe.  .024 inch or .6mm. would be the spec.  6.5 mm?  You would need some great coils!

After putting those plugs through so much torture new ones might be a good idea.

To attempt carb tuning when ignition, fuel delivery or mechanical problems, including vacuum leaks are present is like pissing up a rope.

[ducpainter]

Try closing the air screws in the bellmouth 1/8 turn, see if that helps.

I'm pretty well convinced that the CV Mikunis can compensate for air density (pressure/temperature) pretty effectively.
The FCR's, eh, not so much.

With the FCR's on my M750 I noticed a difference in running quality with a drop of 600 feet of altitude and 20 degF on my previous commute home from the shop.

Can I access said screws without taking anything apart?

[koko64]

Yep. Take off the airbox lid and filter to access the slow air jet screw. You need a long thin screw driver. I ground one down. I forget which port in the bellmouth it is. The smaller jet will be the one

[ducpainter]

Yep. Take off the airbox lid and filter to access the slow air jet screw. You need a long thin screw driver. I ground one down. I forget which port in the bellmouth it is. The smaller jet will be the one

I thought you said I didn't have to take anything apart?

[koko64]

Well just a smidge.

[ducpainter]

Eric spent a couple hours with it on the dyno and the gas analyzer.

I'll work on technique for now.