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Main Area => General GS500 Discussion => Topic started by: danci1973 on July 27, 2004, 07:53:18 AM

Title: Carb syncing
Post by: danci1973 on July 27, 2004, 07:53:18 AM
Hi!

After cleaning the carb and installing new main jets, it's time to put things together. This probably includes carb synchronisation.

I've made the DIY sync tool and it works like a charm - I've used engine oil as the 'medium' cause watter was too thin and was sucked up in a moment.

However, I have one problem... If I sync the carbs at idle (~1200RPM), they are not in sync when I apply throttle (I only went 1/2 or even less, as I don't want to upset my neighbours)...

Is this OK or do I have a problem? Could the sliders/springs/diaphragms have anything to do with that?

Thanks, D.
Title: Carb syncing
Post by: scratch on July 27, 2004, 12:52:24 PM
When I finally got mine to stay synched all the way to redline, I realized it was the butterflies. I watched them as I pushed on the linkage, all the way open; with the carbs off the bike. But, yes, the other things can affect sychronization. Try synching the butterflies all the way open.
Title: Carb syncing
Post by: 500rider on July 27, 2004, 06:58:14 PM
Don't know for sure but the vacuum guage that I have says to use it at 1750 rpm.  I think this is more for the operation of the guage than anything else.  However, to sync the butterfly valves I would think it would make most sense to do it with throttle barely open because this would be where a slight difference in valve opening between the two would make the biggest difference in vacuum.  

This is just my own thought since I don't have any real experience with this.  Your sync problem at higher rpms could be due to a leak somewhere.  You didn't lose one of those tiny O-rings that go under the diaphram cap did you?

Rob