vapor lock, and more

William K Denton wkdenton at
Fri Aug 14 15:16:32 PDT 2009

Jim said, "The manual petcock is only as good as the operator as I found out 
this morning."


Agreed.  However, at least with a manual shut-off, you can correct the 
"behavior" [no one to blame but yourself].  With a vacuum shut-off tap, you 
are at the mercy of the rubber supplier's QC and the ravages of time and 
fuel reformulation effects on elastomers [everyone to blame but yourself].

On the brighter side, the OEM petcock packing (4-hole rubber gasket P/N 
43049-1075) is cheap (<$5.00) and plentiful, as it is used in Vulcans, 
ZX6's, ZX9's ZRX's, GPz's and ZX11's.  At that price, one should just add 
"replace every five years" to the scheduled maintenance routine in the shop 

Bill Denton
Yardley, PA
wkdenton at
Lazarus Cycleworks, LLC
Breathing New Life into Old Bikes 

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