Auto petcock

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Auto petcock

seestheday
After 1981 apparently all cb750's had auto petcocks.  I read on a separate forum that removing it will fix cold start issues and a number of other problems and didn't cause any issues as long as you always remembered to turn off your regular petcock.

I removed it last night when I put my carbs back on my bike and believe it fixed my cold start issue.  Previously it wouldn't start if it had sat for a while and it was colder than about 8 degrees celsius without getting warmed up by a space heater.  Last night was near zero degrees (about 32F for those of you in the US) and it started without issue.

Does anyone else have experience with these?  Is there any reason to keep them?
1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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Re: Auto petcock

mikefootusa
Lol...I took mine off for the same reason...didn't fix my issue.
In 1972 I had to make a choice...quit riding...or quit drinking.  God says it's safe to get back in the saddle now...at least I'm still alive...and feel more alive with the wind in my face!  Now riding "Helen Black"...1982  CB750SC.
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Re: Auto petcock

TOOLS1
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In reply to this post by seestheday
It was probably due more to the cleaning of the carbs. Cold starting is usually caused by the pilot jets being plugged. Also I never turn my petcock to the off position unless I am removing the tank, or line. It is my opinion that as long as there is pressure on the float needle against the seat; there is not any space, for dirt, or other contaminants, to get in that space. Also it would prevent to congeal in that space.
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1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
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