Having Drivability issues (long)

[Momz]

I recently completed my bobber Valk and today was the first day that I was able to ride it. It didn't take long for it to start acting like it was running out of gas. We stopped and I filled the tank and made sure the petcock was turned to the "ON" position. And the bike seemed to run fine for about 10 miles, except the idle was excessively high. We stopped for coffee and let it cool off somewhat. Then the idle was readjusted to 900 RPM. For the next 15 or so miles this bike ran like never before and I couldn't be happier. We stopped again for coffee and when we were about to leave I stalled the bike. I restarted the bike and it just didn't seem to run right. After traveling about a mile or so it seemed to lose power and eventually just died. I quickley opened the gas cap to see if there may be a sucking sound due to a kinked vaccum hose. NADA! I restarted it again and I seemed to have very little power but I was on the side of the road and at least 8 miles from home. I decided to baby this bike back home when it suddenly started to run great again. So it ran like a better than new bike until I got about 2 blocks from home when it started to backfire on deceleration on the right side. I was able to get home and it seemed better when I put it in the garage.

My riding partner, Kickstand noticed that the vaccum line from my petcock was at 180 degrees rather than 90 degrees on his bike (this my fault due to my rebuilding it). I also used rubber vaccum plugs when I did my Desmog rather than use the OEM plugs and noticed that they are deformed (as in sort of sucked in).

I also replaced my petcock screen and there was a black plastic ring/spacer along with the screen and o-ring. What is that for? I did not see one when I took it apart.

Any help would be appreciated, especially by those who have rebuilt there petcocks and desmogged their Valks.

Thank you

[quexpress]

I also used rubber vaccum plugs when I did my Desmog rather than use the OEM plugs and noticed that they are deformed (as in sort of sucked in).

I've desmogged in 2003 (or 2002...) and have then replaced the OEM vacuum plugs with generic rubber ones. They have never caused a problem.
Did you check your fuel hose (from the fuel tank to the T at the carbs)? It might be kinked (this has happened often on many Valks).
Hope this helps.

[F-106]

I would pull the tank and get a good light and mirror and look over everything you did. you may have kinked a line and did not notice it. also did you have the tank repainted? if so i know some painters defuel and put water in the tank before they spray. you may have to drain the tank and install fresh gas.

[Madmike]

If you do pull the tank off to visually check you could check the function of the petcock if you have a mity vac and prove that it is functioning.

[Thunderbolt]

trying to remember what would happen if it were at 180.  Probably would work.  I think I would take the tank off again.  Set it on a flat table with the petcock hanging off.  I did this when I rebuilt mine.  Put a length of vacuum line on the petcock and with gas in the tank and a catch can underneath, pull a light vacuum on the vac line.  With the petcock in the on or reserve position, you should get plenty of flow.  Also the vacuum should not leak down.  Can't remember about the spacer you mentioned.  Maybe it was underneath the o-ring.

[John U.]

Momz, I have a spare screen and it has the spacer/sleeve also. There wasn't one on my bikes when I rebuilt their petcocks last year. I see that on HDL's microfische the spacer isn't shown. Maybe the same part is used on a different model, needing a spacer.
It kind of sounds like engine heat might be causing something to open up a vacume leak.

[lee]

The black plastic spacer goes around the top of the stand pipe.  The outside of this spacer goes up inside the screen. It keeps the screen centered on the stand pipe.  If there is a bend in the screen it could cause more of a restriction of flow without the spacer. If you are going to take the tank off again I
would put the spacer in.