Bike dies instantly without choke? Vaccum line maybe?

[Guest]

Hey everyone!

So the bike will startup and run when the choke is on, but the moment I try to rev it or turn off the choke it dies. Is the vacuum line that goes to the petcock necessary to be blocked or connected for the carbs to work properly? Just got the new petcock, but I want to clean the tank before I reuse it.

Also is it enough to have the carbs constantly connected to a fuel source, or is filling up the bowls enough to get the bike to at least run (so I can tune it up)?

Thanks!

[Redman]

Welcome to GSR.

I dont have specific expereince with the 16valve engine, but your sitatuion is more specific to the carbs.

What you say about will start on choke but not rev and cant run without choke is a very common symptom of carbs needing a good cleaning. THink of each carb as being really 3 carbs, the choke(enricher) carb, the low speed carb and the high speed carb,... and maybe only the choke (enricher) carb is working. THe low speed is clogged up, probably.

What is in bowls is only enough for a short portion of a minute before is too low for good operation.

Do need the vacuum line to operate the petcock in ON and REServe position. Not needed in PRIme position.
If vaccum line disconnected from petcock, will want to plug the line so not a vaccuum leak.

Where in Michigan.....?

[fastbysuzuki]

As Redman says it sounds like your carbs need stripping and cleaning tutorial here http://zeus.mtsac.edu/~cliff/storage...d_Tutorial.pdf

To run the bike for tuning (after you have done the above) you will have to have a constant fuel supply either from the tank or something like this set at the tank height.

(For illustration purpose). https://www.toolstop.co.uk/sealey-ms...oaAjJJEALw_wcB

its possible to adapt something yourself

[Zaos]

Thanks for the replies guys. Guess I should have led with I cleaned and rejetted the carbs a few months ago (no fuel was in them since then) to the best of my ability without actually dipping them in carb dip.

The carb boots are REALLY stiff so I'm wondering if those could be leaking vacuum too. I didn't have a constant fuel source connected so that may have been it too. Also, didn't have the vacuum line blocked off and looking at how it's connected it makes sense why it should be blocked at the very least!


I also replaced all of the o-rings within the carbs, and have new carb float bowl gaskets that should be here on Tuesday.

I figure this bike needs a lot of love, because when I got it the valve cover "gasket" was a cutout of an old pepsi box!

I'm near Grand Rapids, are you close by?

[Zaos]

Thanks for the carb rebuild link, didn't even think to check the height of the floats to make sure they are within spec.

[Redman]

"Good carb cleaning" is complete dissasembly and soak each in carb dip (Berryman or such) for 24 hours at least. ANd poke out various ports with a wire before the dip. As described in the "carb cleaning series" that has been mentioned. SPraying carb cleaner here and there will not do it if various passages are clogged up.

I am directly west of GR.
Grand Haven.

Stiff boots are not a problem, other than making removing and installing carbs difficult. Cracked boots cause air leak, typicall cause of increase idle as engine warms. The o-rings in boot up aaginst the heads can cause the same.
If the boot orings are same vintage as the "really stiff" boots, they are probably shrunk and stiff.
See "Cycle ORing" website for good deal on replacemnt orings for the carb boots and carbs them selves. (Is a fine GSR member doing us all a good service.)
.