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vacuum line, petcock to carb


G-man
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I've got a vacuum line running from the petcock into one of the carbs, whereas the other carb just has a rubber cap on the vacuum nipple. Is that normal, or should the vacuum line split out into both carbs?

The bike runs good and all, so I figure I'll leave well enough alone. But, just askin'. Am I wrong to assume that hooking up the line to the other carb as well would increase the fuel delivery, making it too rich a mixture, which will then require screwing with the carbs to calibrate things out again?

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I've got a vacuum line running from the petcock into one of the carbs, whereas the the other carb just has a rubber cap on the vacuum nipple. Is that normal, or should the vacuum line split out into both carbs?

The bike runs good and all, so I figure I'll leave well enough alone. But, just askin. Am I wrong to assume that hooking the line to the other carb as well would increase the fuel delivery, making it too rich a mixture, which will then require screwing with the carbs to calibrate things out again?

No all it is Gene is a vacuum operated fuel tap (Petcock), when the engine is running a vacuum is developed in the manifold, this vacuum pulls the diapragm over in the fuel tap, thus allowing fuel to the carbs. So its not any benefit to split the line to all manifolds because a vacuum is a vacuum is a vacuum and a vacuum is all it needs ;)

Heres some info, dont know if its readable, maybe if you print it, plz let me know.

FuelTaps-13.jpg

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Hokay, that makes sense! Vacuum line, right...not like it actually delivers fuel. Thanks a bunch, dude.

And it's not a regulator, it's either on or off.

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And it's not a regulator, it's either on or off.

Cool, got it, thanks.

I yanked out the air filters the other day to take a look'see at the suckers. Oh oh, not good...foam all crusty, torn in pieces, tsk tsk tsk. No aftermarket filters available, and the OEMs start at $27 each.

Hmm, I do have some foam left over from relining my bucko helmet. Surely I couldn't, I wouldn't, I mustn't. Well, worth a try. I ripped all the old foam off the air filters, cleaned those bad boys out, stuffed a piece of foam in the intake side of the filter box, pushed in the cleaner, closed it all up and went for a long ride. The bike runs groovy.

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Cool, got it, thanks.

I yanked out the air filters the other day to take a look'see at the suckers. Oh oh, not good...foam all crusty, torn in pieces, tsk tsk tsk. No aftermarket filters available, and the OEMs start at $27 each.

Hmm, I do have some foam left over from relining my bucko helmet. Surely I couldn't, I wouldn't, I mustn't. Well, worth a try. I ripped all the old foam off the air filters, cleaned those bad boys out, stuffed a piece of foam in the intake side of the filter box, pushed in the cleaner, closed it all up and went for a long ride. The bike runs groovy.

I got some air filter foam that was the right thickness and carfully cut it to fit and put it on where the original was. Then I ordered new ones from bike bandit and kept the old ones are spares.

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