1150 carb synch

[Guest]

Ok, carbs back on. Still have no vacuum on the #3. The carbtune is working fine as I switched lines around just to make sure. I can get vacuum on all three cylinders EXCEPT #3. I still haven't been able to do a compression test yet as I haven't hunted for the adapter but I'm really thinking that there is no problem there as the bike will throttle fairly well, but...you never know. Can someone answer this for me. Is there anyway to adjust the vacuum on #3 or is it the one carb all the rest adjust to? I know the proper sequence to synch in case anyone is wondering. It's just that I can move the vacuum up on each cylinder by playing with the synch screw except #3 or course because it doesn't have one.

 

[Guest]

Put your finger over the #3 spark plug hole and kick the starter. Does it blow your finger off the hole? If not you have problems.

 

[Nessism]

There is no such thing as a #3 sync adjuster, because you don't adjust #3 by itself. You adjust #3 and #2 at the same time until they are level. Then you adjust #1 or #4, order doesn't matter, until they match #3/2.

Must be massive vacuum leak, or no compression. Does the cylinder fire when running the bike? Does the exhaust pipe get hot?

 

[chuck hahn]

Is the adapter fully seated in the port? Cracked guage hoses? Splits where they go over the adapters??

 

[chuck hahn]

Opened the shut off valve on the guage hoses?

 

[Guest]

Thanks guys, really appreciate the idea's as I'm at a bit of a wits end with this. Ed; ya that's what has me shaking my head, I can't adjust #2 to #3 because #3 doesn't come up at all. #3 cylinder is firing, no doubt about that. I don't think there a vacuum leak as there aren't many places for one to be. The bike has a 4 into 1 and pods so we're really playing around here but we've put in the proper stage 3 kit so we should have a decent base to get her started and do a vacuum synch. Besides IT's JUST A FRICKIN' VACUUM SYNCH, how complicated can it be??? famous last words... As for the gauge itself, everything is fine, like I said I moved the hoses around to make sure everything is working and all is fine. Not sure what you meant by "Opened the shut off valve on the guage hoses?" please enlighten me.

 

[Big T]

Got all 4 restrictors in the lines?

 

[salty_monk]

The vacuum port you are connecting to isn't blocked is it?

 

[Guest]

Thanks for all the idea's guys. Checked them all and everything is working, instrument wise. So I went at it one more time. FINALLY..if got vacuum on #3. Now the carbs are synched!! Turns out I had the other ones out too far, as soon as I dialed them in, and had to a fair amount, the vacuum on #3 started to come up...dduuuuhhhhh. Still learning, still learning. One thing about the 1150 for sure is the throttle response is very sensitive to the synch. On the VM carbs it can be out a lot more without having such a poor throttle response. Anyways, she's synched and has the mixture screws set. Not all we have to do is ride it and see what she's doing. Oh, and pray to the GS gods that the valve cover doesn't leak since two of the outer corner screws are stripped Hey quick question, this bike has fresh rings in it so of course the bike needs to have an Italian tune up done to it (the PO never ran the bike once all the top end work was done). Are we supposed to do that before I start trying to muck around with different main jets to get her running right with the new pods and 4 into 1 exhaust??

 

[Steve]

Thanks guys, really appreciate the idea's as I'm at a bit of a wits end with this. Ed; ya that's what has me shaking my head, I can't adjust #2 to #3 because #3 doesn't come up at all.

Nice to see you have it dialed in (finally), but will toss this out there for others that might have read this far.

You don't "dial in #3". Apparently (as you discovered) the sync was rather far off, and it was because all the other carbs were closed too far. That means that #3 was the only one that was firing, but it had to be opened rather far to make enough power to keep the engine running. By opening up #2, it will start sharing the load, which will be evident because engine speed will rise. As you turn the engine speed back down to the factory-recommended 1500-2000 RPM, you will see that #3 now has a vacuum level, and you can match #2 to it. Once those two are matched, you can do #1, then #4.

By the way, don't worry about matching the "10" or the "25" on the gauge, they don't really mean anything for synchronizing the carbs.

.

 

[koolaid_kid]

Not sure, I don't speak Italian.
What is an Italian tune up, btw?

 

[Guest]

"Ride it like a stolen mule" as a friend recently posted. Basically it's ride the snot out of it. I remember hearing about this form of tune up a few years ago on this site, I guess it applies to those bikes that have been left to sit a bit or have never been over 3000 grand. And I found out it actually works some times. Not exactly sure what it's doing, maybe seating rings, blowing off carbon, moving particles around in the carbs and air filters?? I guess it hold true the old saying that a bike meant to be ridden.

 

[Big T]

Rob

Break in means vary the RPMs for the 1st 100-200 miles. do not hold it at a steady rpm for a period of time

Easy enough to do while testing and running plug chops

 

[Steve]

Not sure, I don't speak Italian.
What is an Italian tune up, btw?

I don't know about the "btw" extension, :-\\\ but click HERE to read about an "Italian tune up".

.

 

[Guest]

Rob

Break in means vary the RPMs for the 1st 100-200 miles. do not hold it at a steady rpm for a period of time

Easy enough to do while testing and running plug chops

Ok, sounds like it won't matter too much to the tuning. I had it in my head you needed to really push the rpms both accelerating and on decel while trying to seat the new rings.