fuel starvation likely causes?

[Anonymous]

I seem to have a fuel starvation problem on my 81 GS450E. When I'm pushing it really hard for any amount of time, as in on the freeway against the wind, I lose power in spurts. Fuel starvations seems the most likely culprit.

So the question is: What is the most likely choke point where I'm getting my fuel cut off?

My petcock fritzed out last fall so I removed its spring, making it always open, and added an inline shutoff and filter to the fuel hose. I consequently added about a foot of fuel hose, which might be making funky pressure stuff. I did check my fuel filter and it seems clear. Can't see any junk and fuel flows through it well.

The bike was also not stored over winter. I ran it every week or two. I think the longest it sat was three or four weeks.

So would we guess that I most likely have a clogged aperture somewhere? in the petcock or the carb? Whaddya think?

Michael

[Detman101]

Unless that shutoff-valve is the same size as your tubing I bet that is the culprit. I had the same problem with my petcock before Harrison Clement fixed it with me. The bike would run about 2 blocks and then start coughing. Removed the inline shutoff valve, fixed the petcock and the problem went away. If you're going to use an inline shutoff valve it should always be a bigger one if possible. I had a small one that would have worked for maybe a lawnmower. Sadly, I got it from a motorcycle store...



Dm of mD

[KEITH KRAUSE]

By removing the spring, are you sure the diaphragm is completely out of the way of fuel flow? The extra fuel line length may be part of the problem along with the filter. I've never seen the need for fuel filters. The petcock screen in the tank is all you need. If the tank is passing rust particles, the tank needs fixing.
Did you replace the fuel line? If so, did you get the correct size?
Is the shut-off valve you installed the right size?
If it was my bike, I would re-install a new fuel line that drops down to the carb, no dips, no filter. Then I'd inspect the fuel flow out of the petcock. Then clean out the gas cap vent. Then blow into the two floatbowl vent lines to be sure they are clear. Also clean/check the air filter. If the problem still exists, you'll have to inspect the carbs.

[lhanscom]

Also try opening your gas cap and see if that takes care of the problem. You may have a clogged vent on the tank.

[Anonymous]

Sounds like it's really time to cough it up and fix the petcock and put the hose back the way it was.

Michael