Post by: SPR on May 29, 2020, 11:15:22 AM
All the videos I’ve seen show I presume the older carbs with the screw on the manifold and adjustment done via visible lock screws.
I don’t have either so am I right that the gauge connection is the screw in the picture and adjustment is under each carb top cap ?
Yep basic I know
Thanks
Simon
(https://uploads.tapatalk-cdn.com/20200529/7efc7e8bba67ff0eea521b1db4366af4.jpg)
Post by: K2-K6 on May 29, 2020, 01:50:52 PM
Should have carb number two as no adjustment/fixed as you balance all the others to this one as master.
Post by: SPR on May 29, 2020, 01:54:20 PM
Yes to both questions.
Should have carb number two as no adjustment/fixed as you balance all the others to this one as master.
Many thanks :)
Post by: keithtraffic on May 30, 2020, 07:52:40 PM
I have just complete re-built my PD46 carbs - new just about everything! They are now back on the bike after a big struggle and and it seems to run reasonably just after a static balance (setting all the throttle sliders to the same height), but I do want to balance them properly.
The info I have seen suggest that you should double check the timing and the valve clearances before trying to balance the carbs or else you may get misleading answers - would be interesting to see if those who actually have done it before really did go to this trouble first.
What vacuum gauges are you using - these are something I will have to get.
Post by: Nurse Julie on May 30, 2020, 08:08:26 PM
Post by: K2-K6 on May 30, 2020, 08:39:00 PM
Will be interesting to see how you get on with this.
I have just complete re-built my PD46 carbs - new just about everything! They are now back on the bike after a big struggle and and it seems to run reasonably just after a static balance (setting all the throttle sliders to the same height), but I do want to balance them properly.
Strangely enough bench synchronisation and with gauges are the same thing. Gauges just allow you to complete it without dismantling the carbs from the bike.
Parity of carb slides is ultimately for running at equal combustion under full loading as any significant variation will cause unwanted vibrations in that range.
Admittedly it has the byproduct of smoothness, or improved smoothness, at idle, but it doesn't have the resolution in mechanical design to fully resolve tickover refinements. This is completed by adjusting the idle circuits for each cylinder to produce parity of combustion at this speed range, which do have the resolution to control it. They are in effect individual throttles with micro adjustment.
Post by: keithtraffic on May 30, 2020, 10:46:19 PM
Post by: SPR on May 30, 2020, 10:56:05 PM
So, does that mean that if they have been statically balanced its no necessary to use the vacuum gauges for anything?
I suspect the skill used when static balancing plays a big part - mine looked OK when I had them off but the gauge showed that they were way out
Post by: Nurse Julie on May 30, 2020, 11:03:43 PM
I think if you have access to a decent set of vac gauges, it's worth checking your bench sync if you want to double check the result. We never vac gauge after bench syncing, our bench syncing is so close but, it's takes experience to get it spot on.So, does that mean that if they have been statically balanced its no necessary to use the vacuum gauges for anything?
I suspect the skill used when static balancing plays a big part - mine looked OK when I had them off but the gauge showed that they were way out
Post by: K2-K6 on May 30, 2020, 11:20:00 PM
Above link is a very elegant way of working through a set while on the bench.
Obviously it will give greater accuracy than just doing it by eye.
Post by: Bryanj on May 31, 2020, 08:54:30 AM