Sorry! But I can't richen it.

Okay, I'm sure all of you are about as sick of reading my posts as I am writing them, but I'm still having issuses getting this thing to richen the way it should. First, the pertinent stuff. Its a 1982 550 maxim totally stock. No pods, not exhaust, just all stock stuff. I have 120 PSI in every cylinder per spec. It only has 7500 miles on it, and was parked for 20+ years before I revived it. I have cleaned the carbs 4 times, thinking that I have missed something. After todays fiasco, I'm getting a little frustrated. I put my colourtune in after I cleaned the carbs and re-synced, and I turn the adjustment screw all the way out, and still can't get it to got orange. I'm idling it at 1500 RPMS when I check it. I know the jets are stock from the factory, but could they be too small? I though it might be an air leak at the boots or the throttle shafts, so I sprayed some saryting fluid around, and nothing happened. Please guys any thoughts? any help would be awesome.

 

oops

 

The 550 Bikes run Mikuni Carbs.
The Main Jet and the Pilot Jet can't be confused because they are not similar in design.

1,500 rpm's is not Idle.
15 hundred is Off-Idle and you are getting some Main Jet Fuel along with the Pilot Jet Fuel.
That Mixture would be Rich and the Colortune won't get blue.

You need to Colortune Mikuni's with the Throttles completely closed.
Depending on what you used to Bench Sync the Carbs will throw-off the Mixture because anything thicker than a sheet of paper will have Bench Synced those Carbs with Throttles opened.

Bench Sync the Carbs again.
Use 1/4" strips of Business Card or 3X5 Card.
I've been using the 3X5 Card on Mikuni's because they are so susceptible to
letting Main FUEL Jet Supply bleed-in as soon as the Butterflys are cracked-open.

Get the Idle down to 1,000 -or- 1,050 (Max)
Colortune it with the Throttles Closed.
The AIR and FUEL you need for Idle will be supplied by the Pilot Jets when you have the Fly's closed and depend on the Pilots, alone, for adjusting the Idle.

 

I did bench sync those bad boys, but I'll try that again. If I was getting main jet fuel as well, then wouldn't it be rich? the problem is a lean condition. I'll check it though.

 

You DID pop the Emulsion Tubes and clean all the Air Metering Ports ... right?

We shouldn't be having this much of a PITA to get a Rack of Mikuni's doing the right thing.

That's why I thing you should check the sizes of the Jets. PO's will do whatever it takes to make a Bike "Run" for a buyer.
If those Carbs had bunged-up Fuel Jets and the guy threw whatever he could get his hands on in there just to make it go ... we can't tune it until all the right jets are where they are supposed to be.

I think you should check.
You might need a Magnifying Glass to read the Numbers on the Jets.
I have to have my daughter look at 'em and tell me what they are.
Even with reading glasses on ... i can't see 'em any more.

 

Rick- I checked the sync on those bad boys, and they are benched synced really well. I did of course pop the emulsion tubes and clean out every little hole to perfection. I'm really thinking I have an air leak somewhere. I'm going to order the throttle shaft o-ring set from chacal. Any idea what the stock jet sizes are supposed to be? I ddin't look on the pilots, but the main jet reads 112.5. I'm almost certain the PO didn't change out the jets. All stock screws were pristene when I got the bike. I hammered then getting them out and replaced them all with cap screws. Also, I pulled the caps over the mixture screws. Thanks for all the help by the way! You really know your stuff!!!

 

TEST!
Test for the Throttle Shaft leaks.

Thats A LOT of work to do unnecessarily!
All you have to do is Start the Bike and probe the Carbs with the gas from a Propane Torch.
(Do not light the torch!)

If the revs rise ... leaks.
No spike in rpm's ... OK.

 

Just an update, but I tinkered with this thing again, and got it synced spot on. It does idle a little better now, and there are no air leaks causing my lean condition. I checked, and rechecked that!!! Colortune still shows it lean and I'm 3 turns out. I can hear the engine changing pitches as I turn the adjustment screws out. (quite a few turns really) Is that normal? Maybe I add a few degrees and ride and then check the plugs again. Thoughts?

 

At this juncture I would step back and take a hard look at the whole situation.
You might have a Bike that was tinkered with some.
Maybe you should try bumping-up to the next size Pilot FUEL Jet and have the FUEL Jet supply just a bit more FUEL to the equation.

You'll have more "Room" on the Pilot Mixture Screw to find the right Air~Fuel Ratio without turning the Screw OUT so far you'll be losing the spring-load and having the Pilot Screw change its setting due to not enough spring-load to maintain its tightness from vibration.

Or, ...

You can alter the Pilot FUEL Jet by running the next over-sized Cleaning Tool from a Welders Tip Cleaning Set through the Jet and widening the Jet's Inside Diameter by a few thousandths.

 

This statement caught my eye. The color you should see in the sight glass should be a pretty bunsun burner blue, not orange.

May be for that bike! When I color tuned my 1100 I ended up over 5 turns out on a couple of the carbs. I, like you thought that was WAY to far out but after running for a hundred miles or so on new plugs and a plug check, I only had to 'fine tune' as Rick has mentioned.

 

You are right in that you want a bunson burner blue, but you need to get to orange before you can bring it back into the blue range. All I see is blue, and more blue. The chances it's running lean are pretty good if that's all you can see. I think I might try up sizing those jets a tad to see what will happen. I did bring out all the screws anothe couple of degrees, and we'll see what that does.