Strange occurrence TB sync.

[scra99tch]

Alright I close air bleeds
Set 150mV
L/H plate screw to 3.6
Open air bleeds 1/2
R/H plate screw balance at idle
1150 rpm
Then balance with high speed screw.

Barring any problem with my syncpro I am having something unusual happen.

The right side will drop out or stutter as you can see on the sync fluid gauge when going above 3k. I'll go back and clean out and refill the syncpro.  And go over my steps again, but I am thinking something else is happening. 

When the calvin pings is seems to come from the right side.  If that matters. 

Valves were set at begging of the summer. 

I do have something in the right side muffler but experience it even with the muffler off. 

Any thoughts?

[scra99tch]

Slight chance of burnt intake valve a possibility?

[oldbike54]

Slight chance of burnt intake valve a possibility?

 Very doubtful , especially an intake valve . I would check for an intake leak , or a valve out of adjustment .

 Dusty

[fotoguzzi]

how many miles on this motor?

[scra99tch]

26k

While I check valve clearance, I'll open up the intake boot and send some compressed air down spark plug hole at TDC.

[rodekyll]

I don't think it's the idle sync.  Assuming the columns are pulling equally up to the problem point, even if the tps setting is wrong, it would affect both sides.  So equal vacuum up to that point suggests the initial baseline and synch are pretty close.

Exhaust restriction?
bad injector?
bad plug/wire/cap?

Can you drive through it to a higher rpm where the sputter goes away?

I know a phase sensor can cause midrange stutters, but I don't know if it's one side or both that gets affected.

Does that bike have air bypass screws?  Are they set to specs?  On my 15M cali I find odd things happen in the 3k - 3.5k range when the screws are messed with.

[fotoguzzi]

bad injector?
bad plug/wire/cap?

 

on the offending side, is the butterfly pivot loose/worn?

[scra99tch]

I'll have to get back to you tomorrow.

There is something in the muffler, welding,slag or a bolt right behind the db killer.  These are stock and sealed only chance I have is to open me up and weld closed.  But this is not it because it behaves like this with muffler off from what I can tell.

Goodnight and thanks

[scra99tch]

Getting 150 psi cold with WOT for compression.

[guzziart]

Hey Scra99tch,

FWIW, my Sync Pro worked great for several years, last spring I was not able to get consistent read...very frustrating.  After an irritating hour and a half, I discovered one of the Sync Pro segments was slightly low on fluid. Problem resolved.  I suppose some of the fluid evaporated over the years.

Good luck!

[dl.allen]

same here I have to add fluid to the sync pro since it sits out in a hot garage.  Also I have to calibrate it almost every time I use it off of one jug first..to get the bars even.

Set it up on one jug and see if both bars are pulling even up and down the rpm range.

[scra99tch]

No quite resolved, but I believe it was just a mishap on the R/H plate screw.  I am not liking my syncpro though several times I had to re do the fluid as it would just be way to high on the meter at idle.  Luckily I had my twin max (which also sucks) handy which I thought was broken but it worked enough to achieve balance. 

[rodekyll]

The synch pro (I have the 4-tube model) needs to be balanced and the column level set before use.  Someone posted the balancing procedure above, I think.  You run a T from the meter to one vacuum spigot and adjust the columns to match.  The other part of the setup is to make the columns a reasonable length.  That's done with the screws too -- just run them up or down until the columns are even and the height is where you like it.

These things don't really care what you use for fluid.  I've used colored water, ATF, mineral oil, glycerin, etc.  Just something with enough contrast to see in the tube.  If you don't like the super-secret motion pro sauce because it's too jumpy, bubbles, breaks up or whatever, try something else.

I had a twinmax.  I think I sent it on to my son on account of I only used it as a travel tool.  When I was home I used the motion pro, since it's soooo much more stable and readable than the twinmax.  Also, twinmax doesn't require batteries.  I hate batteries.