Mystery at the Carb Synch

[Riding Again]

I did a bench synch prior to starting using a small, straightened paper clip wire as the clearance amount. All four carbs were set to the same level. Prior to installing them, I also held them out to the sunlight, viewed down their throats [smiled to myself--unknowingly cursing the project by this--thinking I'll be riding within 20 minutes] and seeing that they all had the same clearance at the butterflies.

I don't remember which way to turn the screw to move the gauge which way, but you want to OPEN #2, not close it.

The vacuum level is measuring the restriction imposed by the throttle plate (butterfly).
Since the vacuum level of #2 is higher, it is telling you that it is closed more than #3.
Opening #2 will reduce its vacuum level to match #3.

I was thinking that I was measuring the volume of air through the carbs, hence my statement of closing the butterfly--but as you described it, it makes more sense that I need to open it.

I believe my next steps are 1) retry the adjustment on #2 by OPENING the butterfly, then balance the other two; 2) if unsuccessful at 1), then check the compression on the cylinders; then 3) pull carbs, re-bench sych, and check the mounting of the new boots and o-ring on #3.

Thanks for the advice!

[Nessism]

Bench sync is relatively unimportant. I just eyeball the butterflys and then vacuum sync once the carbs are on the engine. Most likely you will get #3 to come up once you play around with the adjuster more. I can't remember which way to turn the screw to get the balance, I just try one way and if it doesn't work I try the other. You should be fine.

[Riding Again]

Thank you all!!!!

I did just need to play with it more and succeeded! So now I have a bike in service!

Bike prep this year has been a small journey: Rewire the R/R [Thanks Posplayr for the instructions, comments and help]; add in an Eastern Beaver fuse box; clean all electrical connections; install new plug caps; rewire the headlight cut-out mod for starting; figured a way to install multiple relays (http://www.thegsresources.com/_forum...php?t=194636); install a GPS (and shield the cables hopefully from ignition RF noise; replace both sets of air boots [engine and air box sides]; new o-rings; painted the carbs; and attempted to polish a couple of parts [Will work more on that next year].

I have some additional carb jetting questions, but that'll be a new thread and hopefully those in the Colorado area could provide some feedback. I think mine are jetted for sea level and not for 4500-5000 ft.



NOTE THE SINGLE GROUND POINT!





SEE THE POLISHED CAPS AND COVER


AND DON'T THESE CARBS LOOK GOOD

[Steve]

Thank you all!!!!

I did just need to play with it more and succeeded! So now I have a bike in service!

Bike prep this year has been a small journey: ... add in an Eastern Beaver fuse box; ...
rewire the headlight cut-out mod for starting; figure a way to install multiple relays

With that great fuse box, you should not need more than TWO relays.

One will be controlled by the ignition key and will feed the switched fuses on the box.
The other will be your headlight cut-out.

Since the fusebox is getting good power straight from the battery, instead of running through the ignition switch,
there is a very good chance that your coils will be getting full voltage now. As anyone should,
check your actual voltages before deciding whether the coil relay mod or any other relay mod is 'necessary'.

If you need help with the headlight cut-out, let me know, I have a relatively easy way of doing it.

.

[cowboyup3371]

You don't need to use anything other than the stock jets. I had my 550T there in Co Sprgs with stock jetting and ran without any issues. You just need to follow the same tuning procedures as everyone else does.