Mikuni RS36-D3K tuning help needed

[Jaymo]

After work today, I removed the pod filters and found that there are two air jets in the bell of each carb.
However, the way the filters are designed, there is nothing that can obstruct them.
It smells very rich at idle. I set my pilot screws to 1/8 turn out. No change.
I also noticed that I have some gas spitting out carbs 1 and 4 at idle. In fact, it washed some of the filter oil off of those two filters.
I also noticed that the stream of gas from the accelerator pump nozzles is hitting the slides.
So, I need to readjust the pump to stop from squirting fuel onto the slides.

But, what about the gas spitting out the carbs at idle?
These are brand new carbs, and I wouldn't think that the floats would be sticking, but I've been wrong before.
I guess I could whack the sides of the carbs with the plastic handle of a screwdriver and see if that improves things.

Could the restrictive OEM exhaust be causing this?
What else do I need to look for?

Thanks guys.

Also, I used carb cleaner to check for vacuum leaks. None found, so far.

[BrettS]

Not sure there is anything that can be obstructed on these?
There are various compounds you can use. I like to use carb cleaner.

[Jaymo]

I just checked out the aviation permatex, you can’t get any better than that lol. But I was told to leave the gasket out. Quick easy check to see if they are leaking though.

Spray WD40 on them while it's idling and watch/listen for changes in idle speed?

I should probably pull the pods off first, to make sure they're not blocking any of the ports on the carbs.

[BrettS]

I just checked out the aviation permatex, you can’t get any better than that lol. But I was told to leave the gasket out. Quick easy check to see if they are leaking though.

[BrettS]

Some stainless filler wire I had laying about. I would finally sync them flick the throttle a couple of times and it would be out again. They are a pain in the butt but I finally got a consistent result that was pretty close. With the vacuum balancer on I’m still out a little but I’m not sure I want to try and even attempt balancing with bike running.
I was getting damn good at balancing the cv’s but I think I’ll get the pro to do these running.

[Jaymo]

Agreed.
I'm going to adjust the pilot screws first and see what result I get.
Also, I used the gaskets that came with them and put Aviation Permatex on both sides of the gaskets.
I do know that once it's above about 2000 RPM, it revs to an indicated 10,000 RPM in less than the blink of an eye.

The engine sounds very mean with the Mikuni carbs. It sounds like an absolute beast now.
If I can just get these issues sorted.....

The fact that it gives symptoms of running both lean AND rich on the pilot circuit is what's so confusing for me.
Black plugs=rich.
RPM hanging=lean.
It shouldn't be both at one time.
I'm going to clean the plugs and let it run at idle for a few minutes and see what the plugs look like.
I may have to remove the gaskets and use sealer.
One reason I want to use the Colourtune is to see what color I get both at idle, and when the RPM hangs after throttle release.
Getting this thing running right has been like working on a Colt revolver. It's all a big balancing act.

BrettS what did you use for gauge rods/pins when you bench synced yours?

[BrettS]

I put new manifolds on mine and that was the first time I had leak issues. Holding revs as you describe is a classic symptom.
It’s recommended not to use the gaskets they come with but use something equivalent to permatex ultra black sealant.
I found adjusting back to the factory marks on the carbs no longer had them balanced. I went over it several times and could not find a reason for it. I was a bit concerned I had done something wrong. Not sure if Andy had the same issue but I know he had a lot of trouble balancing his as you can see in the video. The balancing on these is very coarse. As in the slightest movement makes a big difference. I do believe however that being a little out is not as critical as it is on the cv’s.
First thing I would do is check the manifolds for leaks then pull the carbs off and do a bench sync. Then check for leaks again, then do a colour tune.
You may need to play with the jets at a later date but it should run very good as is.
If the plugs are blacking up in the driveway it would be the pilot jet that is too rich, changing the main jet won’t help much until you are out on the road.

[AussiXS11G]

mate - the only advice I can offer is -
make only one change at a time

[Jaymo]

Hey Jaymo,
Check out the video Andy did on fitting these, see below. I have mine set the same as he did copying the fj1200 recommendations. Think it was the 130 mains but it’s in the video.
I believe the recommended setting for the fuel mixture screw is 1/8-1/4. I’m at 1/8 at the moment and it seems to run better.
Being the D3K model I believe you would have had to change throat measurement, ie reduce the distance between carb 2 and 3. Did you re balance the carbs after this?
Andy’s runs a treat and I don’t remember any lag on his when I rode it but I probably wasn’t game to reef the throttle on his as it has plenty more power than mine.
Mine is running bloody good but it still bogs down a little more than I would like in the lower revs.
Did you set the fuel pumper?
Did you rig up a vacuum advance.
I would also check for air leaks at the manifolds.
I plane on taking it in for a pro tune to get all the jetting and settings checked soon so I will endeavour to let you know results although I have the 1200 big bore kit and late model large valve head I don’t think it would be much difference.

Basket Case was where I got the idea for the Mikuni flat slides. My favorite series on YouTube.
Andy is my hero.
I set the fuel pumper. Will recheck it after a few other things.
I replaced the manifolds and clamps when I replaced the carbs.
It runs the same, with or without the vacuum advance.

Since my new plugs are black, I now know that it's too rich.
Time to rectify that, one step at a time.

[Jaymo]

After adjusting the distance between the 2 & 3 carbs, I adjusted the balancing back to the factory, marked position.
I did adjust the accelerator pump, but may have to adjust it again. I'm tempted to have it come in later in the throttle opening.
I have not yet balanced them on the bike. I know I will have to, but want to get it closer to right before I do.
I may have to go ahead and balance them first.
First, I will adjust the mixture screws and see where that gets me.
I need to find my Colourtune.

Addendum: Jonesey :-) I think you hit the nail on the head. Funny thing is, I am a mechanic. Well, they call us breakdown technicians now. I'm the senior field breakdown technician at my dealership.
However, we are a forklift dealership, so I mostly work on LP, electric, and diesel forklifts. Rarely do I see a gasoline forklift.
So, my gasoline fuel system troubleshooting skills tend to be a bit rusty.
That and the fact that multi carburetion is a whole different kettle of fish.

 That's one of the reasons I work on my own bikes and mowers, chainsaws, etc. It's to try to knock the rust off of those parts of my brain.
One of the pitfalls of using laptops, DVOMs, and handheld analyzers all the time is that you start to forget your pre-computerized fuel system troubleshooting skills.
Anyway, I still haven't found my Colourtune.
But, I DID pull the new spark plugs and found that they are BLACK.
My wife saw them and said "Oh, no."
I said, "Oh, yes. This gives me a direction in which to work. Now I know it's being overfueled/running too rich."
So, I'll start off running the pilot screws in and run them out 1/8 turn. After I clean the plugs, that is.
I may have to raise the needle clip one notch. I'm pretty sure I need to swap in the 120 or 125 jets.
I'll go one change at a time, so as not to muddy the water with too many changes at once.
I need to get one of fuel bottles that you hang up to allow balancing the carbs.
Or, I'll just install long enough fuel hoses to allow me to set the gas tank where the seat mounts while I balance the carbs.

The question is should I use vacuum gauges or should I use my Uni-Syn carb synchronizing tool?
I guess I could try the Uni-Syn and if it doesn't work, try to figure a way to stop my vacuum gauge needles from bouncing madly while balancing the carbs.

[BrettS]

Hey Jaymo,
Check out the video Andy did on fitting these, see below. I have mine set the same as he did copying the fj1200 recommendations. Think it was the 130 mains but it’s in the video.
I believe the recommended setting for the fuel mixture screw is 1/8-1/4. I’m at 1/8 at the moment and it seems to run better.
Being the D3K model I believe you would have had to change throat measurement, ie reduce the distance between carb 2 and 3. Did you re balance the carbs after this?
Andy’s runs a treat and I don’t remember any lag on his when I rode it but I probably wasn’t game to reef the throttle on his as it has plenty more power than mine.
Mine is running bloody good but it still bogs down a little more than I would like in the lower revs.
Did you set the fuel pumper?
Did you rig up a vacuum advance.
I would also check for air leaks at the manifolds.
I plane on taking it in for a pro tune to get all the jetting and settings checked soon so I will endeavour to let you know results although I have the 1200 big bore kit and late model large valve head I don’t think it would be much difference.

[Jonesy :-)]

G,day Jaymo
I'm no tuning expert but itd oes sound like its being over fuelled

[Jaymo]

My bike is a 1981 XS1100H. It's the US "Venturer" touring model.
Long story short: Original BS34s had a broken float post on #4 carb. Replaced them with Keihin CVK36 from a 2005 ZRX1200. Had some issues with them from the start. Ended up with 3 of them flooding. Instead of throwing more money at them, I replaced them with brand new Mikuni RS36-D3K flat slide pumper carbs (yesterday). This allowed me to get rid of the air box which got full of water whenever it rained (still haven't figured that one out), and full of gasoline because of the carb flooding issues.
So, I've got K&N pod copies on them. The carbs were installed  with no changes made to factory jetting. Main jets are 130s.
Since I'm currently still running the factory 4 into 2 exhaust and mufflers, I figure I'll probably need to install the 125 or 120 jets that also come in the box with the new carbs.
So far, the bike sounds a lot better than it has since I've owned it.
My problem is, when I snap the throttle open from idle, the engine bogs and dies.
If I ease into the throttle, I can snap the throttle open once the RPMs get above about 2000, and it roars like a homicidal wild beast.
However, the RPMs hang and drop slowly to idle once I release the throttle.
The pilot screws are 1/2 turn out.
Idle is a bit rough at 1000 RPM and better at 1050-1100 RPM.
I haven't taken it for a test ride, because I deem it unsafe in its current state.
I installed new NGK BP6ES plugs with the carb install, since the old ones were heavily petrol fouled.
The ignition coils are the green, 3 ohm Dyna coils with Dyna plug wires.
Vacuum advance connected or disconnected makes no difference.
When I tested my pickup wires and coil wires last year, they tested good.
I removed the TCI and checked for cracked solder joints and found none. I cleaned the terminal pins in the TCI and harness connectors with Deoxit.
I eliminated the OEM fuse box and went with blade fuses.

What say ye? Adjust the pilot screws richer?
Drop the needle clip one notch?
Swap the 130 mains for the 125 mains that come with the carbs? (after curing the idle/acceleration issues).

It's weird, because It definitely smells rich at higher RPMS and sometimes at idle, but dies upon whacking the throttle open.
Any advice greatly appreciated.