A WARNING and a Question... Options

[NineOneFour]

Set all your mixture screws out 3 turns. You set your mixture screws by ear. Spin them out slowly until the engine drops off a bit. Then spin them in slowly until it picks back up. Leave them there. If you go in too far you get a pop in the face. Back it out again and start over.

If it doesn't drop off your out too far. Spin them in until it picks up.

Thanks Alf

[jmill]

I dont care for the fancy stuff because the only way to adjust the needle is to bust out little plastic holes. I've found that to get a good reading at higher RPMs you have to bust out so many that the idle reading doesn't register.....

Sorry bud but you don't know how to use a sync. (IMG:style_emoticons/default/wacko.gif)

I'm assuming by your comment that they changed the design some in 20 years. Either that or you never check the linkage balance at higher RPM. At higher airflow it would suck the little spring loaded flapper of the old one to the max. I'll let you carb experts run with the fancy plastic stuff. I'll stick with the venturi principle of my trusty uni syn. If it's good enough for an accurate air/fuel mixture why wouldn't you trust it to sync your carbs?

[craig downs]

I've used both syncs and the uni sync sucks. By the time you get adjusted to show a reading you choke alot of air going thru the carb which lowers the idle ever time you put it over the throat. Then you have the bouncing ball to try to give you a reading.

As far as the air bypasses go they should only be used to equalise the flow of the low flowing throats to the high one and thats it otherwise they should be closed. Think about it why open a air bypass if you don't need to.

[craig downs]

I've used both syncs and the uni sync sucks. By the time you get adjusted to show a reading you choke alot of air going thru the carb which lowers the idle ever time you put it over the throat. Then you have the bouncing ball to try to give you a reading.


As far as the air bypasses go they should only be used to equalise the flow of the low flowing throats to the high one and thats it otherwise they should be closed. Think about it why open a air bypass if you don't need to.

[Joe Ricard]

This has got to be the biggest bling leading the blind thread I have seen here in months.

Synch the carbs with the throttles off the idle stops. I prefer around 2000 RPM. adjust the linkage arms to get them the same.
then get the carbs on the idle stops and set idle equally again using the stop screws.

This is of course after you get the low flowing barrel fixed by cleaning out the IDLE JET!!!!!!!!!!

[jmill]

If your idle jets are perfectly sized that would be true. If they're not you can adjust your air fuel mixture at idle with the air bypass without swapping out idle jets.

[jmill]

Joe's right about the plugged idle jet. (IMG:style_emoticons/default/headbang.gif) That would do it.

[Joe Ricard]

There are some other things to "perfectly" :
Get a set of jet reams from CB performance
You can get your idle jets, main jets,
Main air correction, and idle air correction
as well and Accelerator jet nozzles.


Of course having a fully balanced CC'ed and equal compression ratio for each cylinder goes a long way.

My cylinders tune it to a bit closer than a BCH and you can tell it.