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I put this in a new topic just in case. Thanks.

OK, I'm back to this topic. I'm still running rich after the following things:

1) perfect valve adjustment and new belts with proper tension.
2) synched carbs with mercury carb stick
3) adjusted air mixture screws out 1.5 turns and fine tuned while engine warmed to best position that doesn't cause pops while blipping throtlle and to the point where I can vaguely tell an increase in rpm
4) at full throttle, everything is excellent. Pulls hard. Occaisionally, I will fill a jolt, like the rear tire is spinning and then it catches but the tire isn't doing that. I think it's in 2cd gear, I hit throttle, engine rpm increases acceleration good then a jolt and I really get a seat of the pants increase.

Problem:

1) Plugs are black and look a little wet
2) back fire through intake after four or five blips of throttle
3) verticle filter (using pods) seems to be a little wet and black
4) if I downshift at around 5 or 6 and don't apply throttle I can hear pops as the engine rpm decreases
5) have to slip clutch with increase rpm to keep from stalling out

I've replaced all rubber gaskets in the carbs, new floats, new float needle valves. I've got 142 and 145 main jets, going to have to pull them again to see what else I have in regards to the pilot etc. Pretty sure I have K5 needles. Carb boots look fine, have filter pods and Champion RA6HC plugs. I have supertrapp slip ons. Using 93 octane. I'm going to check to see if the choke plungers are seating correctly because at idle there is a faint sound that seems like the choke is on. Kinda of the "airy" sound that you hear when you put the choke on. There are new seals on the choke plungers.

Davy,

I think your pilot jets are probably too big. This jet supplies fuel at idle and all thru the range. If it's too big the engine will run rich all over.

Here is what I'm running in my Paso:

PHF36BD

Main: 155
Pilot: 60
Choke: 75
Needle: 261 AB1
Jet Needle: K-27 Clipped at 2nd lean position.

The bike runs perfectly and returns about 45 MPG when ridden at a medium pace.

It will stall at idle once in a while when warm but starts right up at a touch of the starter. She will also pop/snort thru the intake infrequently if running in slow traffic.

The choke plungers should be pulled to make sure they are seating properly. I had one hanging up when I first got the bike and it drove me crazy. There was dried fuel in the bore that kept the plunger up a little bit. Make sure the choke cable is adjusted properly to allow full seating of the plunger.

Compression?
Leak down?

Here is some more info for you to ponder. The selection of jets in combination is important. Refer to part 2.2

http://www.guzzitech.dk/05/05-10/05-10-03.htm

I'm almost to the point that it's running good enough not to worry about. Although being the perfectionist I am, it will continue to gnaw at me until I fix it. There are just so many things that come into play with carbs, the variables are limitless.

Does anyone have the jet sizes for an older set of Mikuni TM38-85's for the 750, two K&N filters? It runs great with no problems but it is still running too rich. MPG is around 35. Your advice is greatly appreciated, thanks.