Try Toilet Duck Seb, I personally find it a much more mellow experience.

But we are going in the right direction here. Eliminate instrument error first.

But, before Bordo goes hooking up an air line to his vacuum nipple; is that really the best course of action?

Doesn't that run the risk of blowing whatever the obstruction is further back down into the carb?

Not pretending to be any kind of carb expert, just a bit of thinking out loud.

Cheers
TK

 

Could be a lump of foam from the little square valve cover breather filter

If you are blowing air into her Bordo - pull the slide first
and I believe the nipple can actually be screwed.threaded
out with a needle nose grips - making for a bigger hole to
blow whatever is stuck in there out.

You could use a brake bleeder vac such as mity vac etc to
help get it out of there

The top cap gasket is easily reused - float bowls on the other
hand not always

So when you run the motor is downpipe number 4 ----cold or
last to warm ?

 

I'm a visual person, so reading this has to somehow convert written words into a picture through my thick skull. Tell me if I got this right. You put on the Carbtune and No. 4 cylinder showed no vacuum. Is that right? Did you put the hose for No. 4 on No. 3 carb to see if the hose or Carbtune is clogged? Did you try and turn out (counterclockwise) the mixture screw on carb No. 4? Maybe it's seated. Did you try turning the adjusting screw for carb No. 4 out (counterclockwise).

 

By George you've got it!

Now we just have to get Bordo to do it!

If the screw was seated you would notice the poor idling/running I would have thought. My head still says blocked nipple to carb four. I found that adjusting the screws for carbs 1, 3 and 4 caused the revs to increase as I applied pressure on the screw to turn it. When released revs dropped. By seated are you saying that applied pressure to turn would not cause an increase in revs occur??

Cheers, SB

 

Thanks for the tips guys. I wont have a chance to check any of these things until tmrw arvo after work. I'll do the header check first and let you know how that goes. I held the carbtune upside down several times and the rod inside moves freely and appears fine. I will hook them all up again and swap all the pipes over to the different nipples on the top of the carbtune as well as each vacuum point on each carb to ensure its not the tool or any sort of blockage in the pipes of the tool etc. Most of you are saying some sort of blockage in there and I'm hoping that's all it is. If so I'm happy to pull the top off the carb and see what's doing in there. The other three carbs are all synced very nicely and its drawing 19 to 20 on the gauge, which with what I have read on different sites, indicates a reasonably healthy engine. Thanks guys. I'll post up tmrw arvo as soon as I do some of these elimination checks that you have suggested. Cheers.

 

I agree with the guys and that think its a problem with,

1-clogged vacuum nipple (are you tapping in at the correct place? On #4 its the allen head screw that is replaced with the adapter.)
2-sticking carbtune rod (when the carbtune is turned upside down, does the rod move freely?)
3-clogged carbtune orifice (there is a restriction in the carbtune line to keep the rods steady).

Lack of vacuum on #4 would say either, carbtune problem or wide open butterfly on #4. You have proven that #4 butterfly is not wide open.

 

I don't know so much about the Carbtune unit, but the Motion Pro Syncpro has a calibration process that you should do prior to the actual synchronization job.

The synchpro calibration goes somewhat like this. There's a fitting that connects all of the hoses together and then you attach to tool to your static carb and adjust the screws on the tool until all channels run the same reading.

The syncpro also requires a certain amount of headspace for the fluid in the reservoirs to work properly

Does your Morgan tool have a similar procedure? That might tell you if the tool itself is defective

 

No, there are 4 separate channels, side by side. The vacuum lifts rods in each separate channel just like a mercury type system. My brother loaned me one a few years ago and the rods kept sticking and I was chasing the balance for some time before I finally gave up.

 

Also just thinking about this Bordo - check the intake rubber and clamps, it's
not uncommon for the rubber to dry and split or the clamps to loosen or break

 

And a quick and easy check for this is when the bike is idling spray a little bit of aerostart (Start Ya Bastard in Australia), on the intake rubber.

If the revs increase, you have a leak.

I use this method once I have reseated carbs to check that there are no leaks.

I did once however slightly set my partner's eldest boy's sleeve on fire though He was amazingly flame retardant.

Cheers, SB