Triumphrat

01-20-2006, 11:13 PM

Has anyone found it necessary to replace the stock fuel petcock with a "high flow" type to avoid fuel starvation? If so, at what degree of engine modification was this necessary? I want to begin with some modest performance improvements to my new T-100, but I want to resolve this first. Thank you.

RedBird · 01-20-2006, 11:26 PM

I believe the main reason some have used for replacing the petcock is problems with functionality rather than fuel flow. The stock one can become hard to turn "on" after sitting for a few days in the "off" position. I have found that if I put a little pressure in the opposite direction from the "on" position (toward "reserve") first, it will turn to "on" with no problem.

When I took off my tank to take it to the painters for matching paint, I drained over 3 gallons from the tank using the stock petcock in just a few minutes. This tells me no amount of modification to the engine is going to use more fuel than the stock petcock will supply. If the stock petcock will not supply enough fuel, you will need to fill up the tank every 5 minutes! Not my idea of riding fun. Now, a drag racer or some other type of short racer may be another situation.

Larry

tommyturbo2 · 01-20-2006, 11:39 PM

My 01 Bonnie has had all the external mods to increase horsepower short of a big bore kit, and racing carbs. It put out just over 68 bhp on a Dynojet dyno, and showed no evidence of fuel starvation. Matter of fact, it was slightly rich when it hit the rev limiter at 8300 rpm.tommyturbo2

01-20-2006, 11:51 PM

Thanks fellas. I guess "fuel starvation" is just advertising propaganda to get me to buy an aftermarket petcock.

Travis

rodburner · 01-21-2006, 01:27 AM

Quote:

On 2006-01-20 21:51, tcook wrote:
Thanks fellas. I guess "fuel starvation" is just advertising propaganda to get me to buy an aftermarket petcock.

Travis

Yep. I believe the stocker is rated in gallons per hour.

2522 · 01-21-2006, 10:01 AM

The petcock has a screw on the bottom for adjusting how tight it is. If you back off the screw about 1/4 to 1/2 a turn, it should correct the sticking problem. You don't want it too loose, just not to stick.
Tony

farky · 01-21-2006, 10:07 AM

I fully agree with Redbird. The stock petcock supplys 2-3 times the amount of fuel that you could ever need. I believe that some guys in the past have had semi-plugged inline fuel filters (At the carbruator T junction) which they mis-interpereted as petcock problems) As far as petcock being hard to open....With mine, it used to be that way but when it started to stiffen I would just move it back and forth about 20 times open closed, open closed. Now it never seizes any more. Maybe the inside gasket upon assembly has a little burr on the casting and I eventually worked it out. Just a thought.

Work that petcock back and forth. Get rid of the fuel filter at the "T", put an external fuel filter on a few inches below the petcock and you will have a trouble free bike. Someday, just a matter of time that filter at the "T" will have you being towed.

Jerry

Panthermark · 01-21-2006, 02:31 PM

I have a Pingel, but I got it for it's butter smooth action, and upscale look.

Shorty · 01-23-2006, 07:44 AM

I share Panther's opinion. The Pingel looks better, operates smoother and doesn't leak like my stock petcock did.

Shorty

Anvil · 01-23-2006, 11:14 PM

Quote:

On 2006-01-21 08:01, Jimi_X wrote:
The petcock has a screw on the bottom for adjusting how tight it is. If you back off the screw about 1/4 to 1/2 a turn, it should correct the sticking problem. You don't want it too loose, just not to stick.
Tony

I'm going to try that. After all that ****ty gas in Kalifornia my petcock started to stick real bad. Never had before. The gas also started to dissolve my paint just inside where the cap treads, it got all soft and spongy. Now that I'm back in the land of real fuel it has set back up. Looks funny, I'll show you next time you see my bike (&me) :brk: :-g