Why should your 2 balls hang lower

[arveejay]

My explanation as to why when synching carbs, center 2 balls sit lower. Next time you have an opportunity to inspect your carbs, take note where your throttle cable hooks up. If you lift at that spot you will notice that because of the springs located between the carbs, the center carbs open earlier than the outside carbs. That would explain why they sit lower. Once the springs collapse, all butterflies will lift evenly. If they are not set up with the balls sitting lower, when throttle cable is applied, the center carbs will open first and do the majority of the work. Does this make any logical sense?, Or am I just saying this to keep from being deleted?

[redliner1973]

I posted a question on that earlier, but it seems with your explaination that since teh 2 inners open earlier, that the balls should be Higher rather than lower, as the vacuum goes down when the throttles are opened, and would go down just enough to match teh outers until they 'caught up'. I was told it may have something to do with the #2,#3 exhaust flowing slightly better than the outers.

[arveejay]

I thought that as you added throttle and the butterflies open, more vacuum would be shown as more open equals more fuel thus more revs equals more vacuum. Now I'm not sure.

[moto_dan]

My understanding for the difference in height has to do with compensating for the inner cylinders running slightly hotter thereby changing the tuning requirements. But, for most of us syncing the carbs equally is good enough.

[gsBert]

i believe that all butterflies should be opening at the same time... the springs are there only so the synch screws dont move with vibration.

the 2 center cylinders should be jetted slightly richer, but they should all be synched the same i think.

[mark]

Love the title of your thread. I've got a set of vacuum gauges so I don't have any balls at all. 8O

[Guy]

Lookit........
The main jets are the same across all four carbs. When properly set up, the inner two carb butterflies are open fractionly more than the outer ones. This is to slightly richen the inner two cylinders to compensate for them running hotter. When you open the throttle you lose vacuum, when you close it you gain vacuum. That's why the balls are higher on the outer carbs. Simple.

[gsBert]

i have all my butterflies open at the same time by the same amount.
thats how i have my carbs adjusted
am i doing it wrong?

opening the butterflies more will let in more air sucking in more gas. doesnt affect the mixture but just the quantity.
mixture is affected by jetting.

but im new to carbs and ill admit theres a lot of stuff i dont know

[arveejay]

Well, I guess I didn't give that quite enough thought.

[Guy]

i have all my butterflies open at the same time by the same amount.
thats how i have my carbs adjusted
am i doing it wrong?

Yes.

[Billy Ricks]

The reason for having the different settings on the inner two cylinders is due to the stock exhaust design. When you run an aftermarket pipe ypu set them up all the same.

[gsBert]

ah ok, that makes sense.. or does it?

yes it does. the stock exhaust is poorly designed... lol, of course it makes sense...

no wait a second, it doesnt make sense...

why would you want 2 cylinders to get more mix before the other two when you crack the throttle open? i mean, all the pistons are connected to the same crank right?

can you explain it to me billy? im honestly confused...

glad to know that i dont need to worry because of my 4:1 though...

[Billy Ricks]

It's been a long time since I got the scoop on the reason, but I believe it had to do with the crossover on the exhaust.

[Guy]

The inner two pots on an air cooled in line four cylinder engine will aways tend to run hotter than the outer two, stock exhaust or not. That's why some manufacturers use bigger jets on the inner pots, and others (suzuki) set the inner carbs to run fractionally faster/richer.