Steamer Jeting

[Belco100]

I have had a good look through the archives and couldn't find a definitive answer. 

My newly acquired Steamer has never ticked over or run properly low down. I just fitted a set of stick coils and she was no better, so not coils or electrics, so I dropped the carbs off and sure enough two pilot jets completely blocked. But I was more amazed with other bits inside; the slides have two 4mm air holes, never seen that before, normally I run a single 2.5mm hole, and 120-115-120 main jets whereas I was expecting 105s? I stuck some old unblocked pilots in which I had previously unlocked with small drill so no idea what they are and stuck it all back together. Now starts and runs fine, so ordered some new 40 pilots to go in.

My question is if I go straight to Daytona jetting 125-120-125 and remove the second blanking plug will it run OK with a otherwise standard engine? 

[Sin_Tiger]

Can never remember jet sizes for the life of me  I was hoping it was here somewhere, I could have sworn Mustang had them listed in a post. Search throws up a few references but when you try to access them it jumps back here, we might have lost a few words of wisdom 

If the second port on the slides has been blocked, have a look at your needles, my first one had a "Factory" Kit fitted and it was like a Massey Ferguson until it hit 3k and then it  , not good around town.

[Beernard]

Hi Belco,
I agree with Sin about the Mustang posts about tuning. There was a lot of info from him. I will have a look around for it myself, and I think you will be greatly helped if you can find this stuff.
I'm sure he had a post about the holes in the slides. He also, many times, said "don't mess with carbs or snorkels".
Also, my Trophy is 125-120-125 standard (Mikunis). My Tiger is 105 standard. Remember they have different cams, CDI, jetting and snorkel-blanks (both open on Trophy).
I will have a look at my Tiger carbs and see how many slide-holes (they are currently off the bike).
BTW I'm amazed she ran at all with 2 idle jets blocked! Maybe you have already fixed it!
Any way good luck and I will get back to you about the slide-holes and any Mustang info I can find.
Regards, Bern.

[Beernard]

Me again. I searched Carbs and it looks like there is plenty of Mustang (and others) stuff there. Lots to look through, though!
Good luck.

[Beernard]

Gday Belco. These are of the slides from my 1993 model. The holes are 4mm. The slides in my 1994 are exactly the same.
Hope this helps in some way.
Regards, Bern.

[Belco100]

Cheers Beernard, I had changed slides to a single 2mm hole, will try the 2x 4mm hole slides back in it. I have gone down to 112.5 jets, smallest I have. Will order some 105s I think and try them. I have put new pilots in as thy were gummed right up and starting and tickoever is good now, but tries to die around 4,000 if I open it quick but happy cruising at 9-mph if I open up slowly.

[Sin_Tiger]

This is what mine had when I got it, the needles had a very small marking "Factory" you need a magnifying glass to see it.

[Belco100]

Right hand airbox blanked off, gone back to the 2 x 4mm holes with 112 main jets with all new 40 pilots. It feel like a complete cylinder goes around 4,000, coughs and splutters but if I slowly back off it catches on all again and goes well.

It starts lovely, ticks over fine, runs on part throttle at 30 mph OK and will cruise at 90 mph OK, just dies completely if you wack the throttle open. Very frustrating.

I guess it is probably an air leak somewhere or pick up coil?

[London_Phil]

Sounds like either a coil going bad, or pickup failing. Do a search on the forum, as there are different behaviours for each, will will help identify.
Other than constant carb problems on mine, I fitted a new pickup, as it was not expensive, and converted to coil sticks, which again wasn't too bad on price.
This made a big difference to the overall running.
Both oem coils and pickup have a known failure rate, so best to eliminate where possible.

[Belco100]

Cheers London_Phil,

I fitted stick coils at my first attempt to eliminate it being a coil - turned out to be blocked pilots which I have now fixed. So not coils. Two steps forward and one back.

Was thinking of changing the pickup coil next?

[Sin_Tiger]

Pick up less likely with the symptoms you describe.

Single coil is possible and relatively easy to swap around. Possible floater in a carb? Air leak is possible with sudden intake depressions but harder to spot and always suspect when you've had carbs on and off several times if the spray technique doesn't highlight it it can sometimes show up on carb balancing. Another one when doing a lot of carb on and off is float heights, easy to knock one off.

[Beernard]

I agree with Sin re pickup coil. When mine failed it would just die when it got hot and start when it cooled down. Hope that helps.

[Bixxer Bob]

Based on what I've recently learned after spending countless hours on V4 carbs,  if it bogs when snapping the throttle open and you're sure that all the jets and air and fuel galleries are clear,  there's a good chance you've got a leak around the diaphram so I'd double check that they're correctly seated and sealed.  If there's a leak there won't be enough depressionto  open the slide correctly when you open the throttle.  The next most common cause is the diaphram spring not being correctly seated, having pinged sideways as the top was put on.

As my catch line says, "I make these mistakes so you don't have to..."