I don't see anything about the petcock there, though.
The petcocks used on these bikes were never intended to be rebuilt but we used to recommend drilling out the staked posts to disassemble the petcock and flipping the "wafer" (round seal with 4 holes with ribs around them) to get a bit more life out of it, then drilling & tapping the posts to accept screws for re-assembly (I think that's what Phantom was referring to). That was a temporary fix at best 15 or 20 years ago and I seriously doubt that any petcock "rebuilt" that way now would last very long at all (ancient rubber hardened by decades of contact with a strong solvent and all).
Unfortunately none of us was able to find a replacement wafer that fit properly and the ones that needed to be stretched to fit didn't last long either.
Fortunately there are affordable aftermarket replacements available.
Re Spring Brook's original question, I think most of those who posted here today have seen this before but I'll add it in case someone else finds this thread who hasn't:
The vacuum petcock has 2 valves, a manually controlled valve that works the same as a non-vacuum petcock, allowing you to select between ON, OFF and REServe and a vacuum valve that prevents fuel from entering the manual valve when the engine is not running.
The carbs on these bikes have a tendency for the fuel in the float bowls to evaporate and fast enough that if they are not used for a week or so the level can get low enough that there isn't enough for the engine to start. The problem is that the vacuum petcock doesn't let any fuel into the carbs unless the engine is turning fast enough to produce vacuum so you have to crank the starter long enough for the engine to supply enough vacuum to the petcock to open the valve for a long enough time for the float bowls to re-fill and it is pretty easy to run the battery down doing that.
You have a few options when that happens:
2) Disconnect the vacuum line from the petcock (this is the small barb farthest from the petcock's main body), connect a short piece of clean tubing in its place and apply vacuum (with a vacuum pump or just suck with your mouth) for about 10-15 seconds.
3) Disconnect the drain/vent line from the petcock (this is the small barb between the vacuum line and the main body), connect a short piece of clean tubing in its place and blow gently into it for 15-20 seconds.
Of course, the whole problem can be eliminated by converting to a non-vacuum petcock.
The petcocks used on these bikes were never intended to be rebuilt but we used to recommend drilling out the staked posts to disassemble the petcock and flipping the "wafer" (round seal with 4 holes with ribs around them) to get a bit more life out of it, then drilling & tapping the posts to accept screws for re-assembly (I think that's what Phantom was referring to). That was a temporary fix at best 15 or 20 years ago and I seriously doubt that any petcock "rebuilt" that way now would last very long at all (ancient rubber hardened by decades of contact with a strong solvent and all).
Unfortunately none of us was able to find a replacement wafer that fit properly and the ones that needed to be stretched to fit didn't last long either.
Fortunately there are affordable aftermarket replacements available.
Re Spring Brook's original question, I think most of those who posted here today have seen this before but I'll add it in case someone else finds this thread who hasn't:
The vacuum petcock has 2 valves, a manually controlled valve that works the same as a non-vacuum petcock, allowing you to select between ON, OFF and REServe and a vacuum valve that prevents fuel from entering the manual valve when the engine is not running.
The carbs on these bikes have a tendency for the fuel in the float bowls to evaporate and fast enough that if they are not used for a week or so the level can get low enough that there isn't enough for the engine to start. The problem is that the vacuum petcock doesn't let any fuel into the carbs unless the engine is turning fast enough to produce vacuum so you have to crank the starter long enough for the engine to supply enough vacuum to the petcock to open the valve for a long enough time for the float bowls to re-fill and it is pretty easy to run the battery down doing that.
You have a few options when that happens:
- If it has been sitting for a few days and you expect that it will be hard to start, before you touch the Start Button, vigorously whack the throttle open several times to operate the accelerator pump and squirt raw fuel into the carb throats.
- If it has been sitting for a week or more and whacking the throttle doesn't help there are 3 ways to fill the bowls:
2) Disconnect the vacuum line from the petcock (this is the small barb farthest from the petcock's main body), connect a short piece of clean tubing in its place and apply vacuum (with a vacuum pump or just suck with your mouth) for about 10-15 seconds.
3) Disconnect the drain/vent line from the petcock (this is the small barb between the vacuum line and the main body), connect a short piece of clean tubing in its place and blow gently into it for 15-20 seconds.
Of course, the whole problem can be eliminated by converting to a non-vacuum petcock.
