Pingel petcock

[The norm]

I thought I would pass on the pingel for our R's with reserve for anyone interested. http://www.pingelonline.com/dirt-atv-fuel-valves/4111-ah615ang.asp

Loren

[hickwheeler]

Nice Loren, I didn't realize they made one with a reserve.

[hickwheeler]

I might be a little concerned if it gets the same flow as the non reserve one. Just me thinking

[The norm]

I asked the pingel guy and Pete about that. They both say that it will flow plenty of fuel

[jcs003]

never seen a pingel with a reserve option.  is this a new thing?

[The norm]

I'm not sure

[Skeans1]

You use to be able to build one with their flanges, nice to see they actually put it together as a kit

[Jerry Hall]

I instruct all of my customers to ALWAYS run their petcocks in the reserve position.  Petcocks obtain their fuel from the lowest level in most fuel tanks when positioned in the reserve position.  Petcocks obtain their fuel from a stand pipe that may be 2 or more inches from the bottom of the fuel tank when placed in the on position.  High performance two strokes that are highly tuned, can burn a piston in less than a couple of seconds or so when the air fuel mixture becomes too lean. 

I have seen a large number of pistons torched on engines that had the petcock positioned in the on position.  The fuel level in the float bowl does not stay consistent when the fuel tank level becomes low enough to not keep the stand pipe on the petcock completely submerged 100% of the time. 

As the fuel level in the fuel tank becomes lower and lower and the fuel is sloshing around, the stand pipe is not providing fuel to the float valve 100% of the time.  The inconsistent fuel supply to the float valve causes the fuel level in the float bowl to stay lower for longer periods of time until the lean condition causes a piston failure. 

A two stroke will need a fuel flow rate through the carburetor of at least 6 gallons per hour when developing around 70 hp.  You will never use 6 gallons per hour if your engine develops 70 hp but the fuel supply past the float valve must be at least 6 gallons per hour any time the engine is developing 70 hp to keep it from going lean for the period of time it is at that power level. 

A flow test with a full tank will provides a lot more fuel pressure and flow, so always perform this flow test when the fuel level in the tank is 1 to 2 inches from the bottom of the tank.

[croat1]

So, how do you guys route your fuel line?  Reason I ask is I seen this.  What is the science behind routing with the loop?

[2ndmoto]

I don't see any advantage to that.

I will mention, I put a Pingel on my Banshee many many years ago. The boss that the in-tank filters connect to, sit up higher than the bottom of the tank, which doesn't allow all the gas to exit. Meaning I lost some of my reserve. Some gas was in to tank but couldn't get over the boss.

Not sure if the hondas are different.

Best Regards
-Jason

[The norm]

I have never seen anyone run their fuel line like that?? I wonder what the thought was?

[Jerry Hall]

Who knows what the first guy that put a loop in it was thinking.  The second guy that did it did not know either, but second guy that did it because the first guy was faster than the second guy.

I do not believe anything in physics would support any benefit.  If the fuel flow was very high ( like 50 to a 100 times more than a 200 hp engine would ever need) the extra length of the fuel line will reduce the fuel flow as compared to that of a shorter line!


Physics of flow in round pipe:

1.  Longer lengths always reduce flow.
2.  Any amount of bend in constant diameter pipe always reduce flow.
3.  Bending will reduce the inside diameter and reducing the diameter always reduces flow. (a Mandrel bent tube will always suffer some reduction in the inside diameter of the tube in the bend and clamping areas) Any reduction in the inside diameter anywhere in a length of tubing will reduce flow even in the best with the best designed venturi.


Results I see from my mandrel tubing benders:

1.  With all new dies, followers, and mandrels, the inside diameter of 1.500" od x .o49" wall mild steel, the bend area will be reduced .020" to .030".
2.  A .020" reduction in diameter of a 1.50 x .049 wall tube will reduce the cross-sectional area 2.8%.  The reduction in flow will be more than 2.8%.
3.  Most mandrel tube bender's tooling have some ware and the actual reduction in diameter in the bend area will run around .040" to .060"