carb sync- verdict is in

[twigg]

If these carbs have positive open, positive close, so be it. I was referring to spring returns. There still should be seperate adjustment for idle speed and high speed. Moderators can delete all my stuff if it will help un-confuse the issue. I hereby subtract my plus !!!

 

S'ok ... you have as much right to have confusion cleared us as anyone else

 

Put simply .... The throttle is a two cable pull open, pull closed system. There is a spring which will close the throttles too, which is why the hand grip will spring back. The throttle closes as far as the throttle stop, which is adjustable for idle speed.

 

Here is where the confusion lies .... The cables open and close ALL four carbs, at the same time and by the same amount because the carbs are mechanically linked together and the throttle acts simply on one end of the linkage.

 

In order that the throttles all have the same vacuum, the linkage is adjustable, and that is what you are adjusting when you sync the carbs.

 

In this instance, there is one screw that syncs carb 1 to carb 2 (Left bank) and one that syncs carb 3 to carb 4 (Right bank). When that has been done there is a third screw that sync the right bank to the left bank. ... Job done.

 

After each step, the throttle stop is adjusted to maintain the 1050 idle speed.

 

When that is done you can move on to setting the idle mixtures (the "idle drop" method is close enough) ... Then do the sync all over again.

 

Through it all you shouldn't need to touch the cables if you adjusted the free play first, and because you are syncing on the throttle stop, the cables play no part in the process.

 

Oh ... make doubly sure that the chokes are fully closed or that will bugger up the idle and the idle mixture. The chokes are not traditional "air restrictors", the are actually an extra circuit that enrichens the mixture at idle .... Which is also why you should leave the throttle well alone for cold starts. If you try to gas it you are effectively bypassing the choke.

[Bobby G]

Can I assume that if my RSV starts OK, idle's OK and gets really good mileage (47 - 50mpg), that my carbs do not need to be checked or tuned? I've never done this and have never had it done. All I've ever done is run some Chemtool B-12 or Seafoam in the tank every few months or so.

 

Just checking.

[RandyR]

Can I assume that if my RSV starts OK, idle's OK and gets really good mileage (47 - 50mpg), that my carbs do not need to be checked or tuned? I've never done this and have never had it done. All I've ever done is run some Chemtool B-12 or Seafoam in the tank every few months or so.

 

Just checking.

 

don't touch it....

[SilvrT]

Can I assume that if my RSV starts OK, idle's OK and gets really good mileage (47 - 50mpg), that my carbs do not need to be checked or tuned? I've never done this and have never had it done. All I've ever done is run some Chemtool B-12 or Seafoam in the tank every few months or so.

 

Just checking.

 

don't touch it....

 

 

 

Forget what Randy said... take them carbs offa your scoot and send 'em to me!!

[twigg]

Forget what Randy said... take them carbs offa your scoot and send 'em to me!!

He bookmarked this thread ... He just knows he will need it sooner or later

[muaymendez1]

So i have been reading this topic and also had to google the effect of high speed synching vs idle. I finnally decide I will try 2 tanks both ways.

i synch my carbs first at idle .........Then i decided to roll on the gas. Its synched all the way up till about 4800 rpm.

So I guess I did both high and low carb synch.

?

 

 

am I missing something. I was off about 3 inches of merc either way before the synch and now am withing 1/2 inch or Hg.

[RandyR]

So i have been reading this topic and also had to google the effect of high speed synching vs idle. I finnally decide I will try 2 tanks both ways.

i synch my carbs first at idle .........Then i decided to roll on the gas. Its synched all the way up till about 4800 rpm.

So I guess I did both high and low carb synch.

?

 

 

am I missing something. I was off about 3 inches of merc either way before the synch and now am withing 1/2 inch or Hg.

 

Sounds like your carbs are set up the way they should be. ride it.

[V7Goose]

So i have been reading this topic and also had to google the effect of high speed synching vs idle. I finnally decide I will try 2 tanks both ways.

i synch my carbs first at idle .........Then i decided to roll on the gas. Its synched all the way up till about 4800 rpm.

So I guess I did both high and low carb synch.

?

 

 

am I missing something. I was off about 3 inches of merc either way before the synch and now am withing 1/2 inch or Hg.

No, you are not missing anything - it just sounds like you were confused by people who think it is normal to have your carbs go out of sync at different RPMs. It is not.

 

Bottom line is that if there is nothing wrong with your bike AND you have done the carb sync correctly, they will stay in sync at all RPMs.

Goose

[muaymendez1]

Ok then ride it and be glad all is well.

Thanks for the assurance guys.

Do you think my milage will increase now with the synch.

Also where can one find a mechanical tach so I can set my idle correctly

Or does anyone have a vid clip of thier bike in perfect idle.