fuel leak, revisited

[Ivan]

A sync tool can be made from stuff at lowes for less than $20.

Just use four equal length pieces of 1/4 vinyl tubing about 8-10 feet long, and tee them together in the center. Zip tie them to a yard stick and squirt some automatic transmission fluid in there. Let it settle all the bubbles out and you have a "spirit level" sync tool that is VERY accurate. Just hook one tube to each vacuum port and work the carbs until they balance out. To start, you'll probably just end up cranking it over a couple times and adjusting, so it doesn't suck all the fluid through the engine. Takes some time, but works well, and is cheap.

As far as the carbs, they are simple. Just take your time and be careful, they are a bit delicate. Also, precision and cleanliness pays.

[trbig]

If you take the carbs off you MUST sync when you reinstall. There is NO way around it.

Not to be argumentative... OK, maybe I am.. but I have taken the carbs off and on tons of times without synching them when I re-installed? As long as you simply pull them off, pull the bowls, and don't do anything to the adjustment screws, it should still be there when you re-install.

That being said, if you go in and clean the jets and they were dirty at all.. then yeah, you'll probably need to re-synch.

So.. yes you probably SHOULD re-synch after having the carbs off, but no you may not HAVE to.


Tod

[XSokieSPECIAL]

Not meaning to argue with your super guruness Tod but whenever I've removed the carbs and reinstalled them even if I just adjusted float height I hooked up my sync guages and every time they were way off.

Maybe it's just me that's out of sync.

[T99Ford]

And for the rebels out there...

I have been rebuilding lots of carburetors for years. That said, I am also a realist that even with perfect parts and conditions, eventually you will have a float hang up, even if it is just a great once in a while. I binned the octy on mine since it started leaking and acting up, and I did not feel compelled to waste the time and resources to replace it (it is a good idea, I just don't have the patience to keep those kinds of good ideas in service). I didn't like the look of all the hoses, either. Two fuel shutoff valves for $6 later, my bike never leaks on the floor again. (Of course, sometimes it only runs for about a block and then dies, too). I have found that with the old system, my bike had an embarassing pool under it every time it needed to make an impression, and now at least the embarassment is one block away.
Now, the purists and die hard carb guys on here may not like this approach, and that is ok by me. I have spent countless hours cleaning, adjusting, and otherwise working on carbs too. But, for those who are a little more inclined to not work on their carbs, and avoid the occasional mishap, there is another way...You just have to remember to turn them on BEFORE you ride away.

Just my $.02 for what it's worth. Don't taze me, bro!

[DGXSER]

As to synching, IMO both perspectives are correct. I have "bread tie" synched one set, the other I did nothing but put back on. Both bikes ran fine. I am certain in both cases performance could improve from a good synch. The later (being my first XS11) I can assure you this is true.

Increased or changed performance is the key. Synchronization is not about setting the butterfly to the same amount of opening, but establishing the same amount of vacuum at each intake port to the cylinders. equalizing the cylinders performance to each other. As Tod stated, if you clean the carbs or rejet or even change spark plugs, you can and will effect performance of the cylinders and therefore effect the synch. Maybe enough to be noticable, maybe enough to effect performance, maybe not. Only way to know for sure is to measure it and see. If it runs well enough for you without the resynch and your not worried about an exact performence, then perhaps you don't need to bother.

To do it n the cheap, get one vacuum gage of some type (I use my mity-vac) and hook to one cylinder at a time. More time consuming, but can be just as accurate if you spend the time. YMMV

[trbig]

whenever I've removed the carbs and reinstalled them even if I just adjusted float height I hooked up my sync guages and every time they were way off.

That's different. If you are making any kind of adjustment in there, you're going to be changing the mixture and will need to re-synch. Simply changing out a float needle/seat isn't changing any of your fuel mixtures and SHOULDN'T need to re-synch... but yeah, it is probably a good idea anyway.


Tod