Petcocks on 1980 bikes???

[TheNose]

I have two petcocks. One off of a 1980 GS850 and the other from a 1980 GS550. Neither have a handle to turn them to the different positions. Can someone tell me how they work? How do you know what position it is in. There is a pointed marker on them and the letters PRI for prime, but I don't know for sure how to tell the position by looking. It seems that the full counter-clockwise position is ON and the full clockwise position is PRIME. Do they have a reserve position? Since neither is on a tank, I can't tell by letting gas flow. Besides, I don't think either will shut the fuel flow off. I probably have to order a rebuild kit, but I'd like to know how they are supposed to function first.

Thanks in advance.

Terry

[focus frenzy]

the one for the 850 should have a lever, up and down is on, counterclockwise should be prime, clockwise is reserve.
I have a good functional petcock (80: 1000) collecting dust, you can have it if you want it. it does not have the screen tube but it does work correctly.

[terry]

And the the answer is....................... (drumroll) it doesn't matter where you turn that little slot, it makes absolutely no difference, there is no actual "prime" position on this petcock!

Have a look at the thread "dumb question but.................." I discovered last weekend when I pulled mine apart that the little screwdriver slot thing doesn't do a damn thing because it is under the diaphram, with no mechanical way of redirecting the fuel flow.

Don't get me wrong, the petcock works fine, and with some vacuum sucking that diaphram open the flow rate is very high, but there's no way it'll fill your carbs after a prolonged "lay off" without some outside assistance.

One of the other GS'ers says he pulls the vac hose off the petcock and sucks on it to get that fuel flowing again. I'm thinking about actually installing a "T" piece in my vac hose, then running an additional hose off under the seat with a plug in it, so that if I have trouble with mine after sitting awhile, I can prime it manually. :twisted:

[Hap Call]

...I can prime it manually. :twisted:

That sucks!

Hap

[TheNose]

Leon,

Okay, I'll be a bum and take the petcock if you really want to give it to me. Before you send it, check the distance between the mounting holes to make sure it will fit. The mounting holes on my tank are about 2 inches apart. The mounting holes on my '77 GS750 are about 1.74 inches apart. I need the one that is about 2 inches apart.

Thanks,

Terry

[terry]

...I can prime it manually. :twisted:

That sucks!

Hap

No, I suck!! 8)