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Old 03-22-2012, 09:12 PM   #16
bleaknessengine
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Quote:
Originally Posted by mymindsok View Post
3) Do a fuel flow check or simply rebuild the petcocks. (You always ride with both petcocks open. Right? Right??)
is this really bad to do? i've been riding with the left one on full time, and then using the right side as a larger "reserve."
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Old 03-22-2012, 09:50 PM   #17
Wirespokes
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With both petcocks on, when you get the first indication you're running out of gas, turn one side to reserve and the other off. If you don't fill up before running out on that side, flip the other to reserve.

That way you've got two reserves, or a total of 50 miles before totally empty.

How much more do you need?

Running on only one petcock with possibly a clogged filter screen could be your whole problem right there! At higher RPMs the larger airheads need the flow from both petcocks.
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Old 03-23-2012, 12:35 AM   #18
bleaknessengine
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i wasn't the one with the problem, just wondering.
my bike runs well, but some oil comes out sometimes...
weird, right?
haha!
thanks, though!
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Old 03-23-2012, 09:24 AM   #19
Tankad OP
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i always ride with both petcocks open...
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Old 03-23-2012, 09:41 AM   #20
chasbmw
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I also only use a single petcock, never resulted in a fuel flow problem. If you fit a filter many car ones are for a high pressure fuel system and might well obstruct flow.

Remember floats height, float height.
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Old 03-24-2012, 12:18 AM   #21
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If tapping the carb sorts the problem in the short term, consider that the float mechanism is sticking somewhere. Remove the offending carbs bowl, inspect it for markings where something might rub. If you see such a mark without altering the float height, give the float mechanism a slight squeeze at either end.

Does that float move up and down freely? Is the pin in good condition?
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Old 03-26-2012, 08:56 AM   #22
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So I did a fuel flow check this weekend, and ended up fixing the issue I was having with lack of power and sluggish performance. The problem now is… I did not adjust anything. I did notice that the right carb fuel flow is a lot slower than the left side and I think the left side carb seems to be flowing (maybe) to fast. The left side is also the carb I have to toe-tap to stop it from over flowing…

Could someone tell me where the adjustment screw for fuel flow is located? Also, should there be a gasket between the carb and the fuel bowl? Is it needed, yes or no? I have never had one on this motorcycle.

Here are some pics of both carbs, the fuel bowls, and the fuel flow process. There really wasn’t any debris floating within the fuel bowls, so I think the petcock filters are working fine.

















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Old 03-26-2012, 09:21 AM   #23
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There is no adjustment for fuel flow from the tank to the carbs.... once the petcock is on that is all there is!

I bet you have a partially blocked petcock screen.
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Old 03-26-2012, 09:26 AM   #24
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And the problem was?

So what did you find, and what was fixed, to resolve the power problem? Having you say that it's now fixed is like watching a movie where the hero is in deep shit, and next scene he's kicking back with his sweetie watching a movie and everything's fine.

We shouldn't answer any new questions till we get an answer!!!

But I will... no, there's no control for the fuel flow - it flows till the float valve shuts it off. That's all.

If the fuel level in the float bowls is the normal height, it's waaaaaay too low!!

And yes, a bowl gasket is needed! It keeps fuel from sloshing onto your boot, but more importantly creates an air tight seal so the choke works properly. The brass choke pick-up tube draws fuel from that itty bitty reservoir in the corner of the bowl and without a gasket will have an air leak of magnitude!
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Old 03-26-2012, 09:59 AM   #25
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So what did you find, and what was fixed, to resolve the power problem? Having you say that it's now fixed is like watching a movie where the hero is in deep shit, and next scene he's kicking back with his sweetie watching a movie and everything's fine
I wish I knew how it was fixed, because I’m thinking it will only come back.
This is what I did: 1) I started with the left carb, with the petcock closed, I removed the fuel bowl and checked the float movement and levels. This seemed fine, so I opened the petcock and ran almost enough fuel to fill the container in the picture through it. It seemed to flow fast and consistent. 2) I did the same thing on the right carb (with the fuel bowl back on the left carb)… this one seemed to flow slower, but consistent as well. 3) I noticed that the fuel level was not as high as I would expect it to be on the left fuel bowl after testing the right side, so I went and got a bigger bucket and started a fuel flow check with both fuel bowls off the motorcycle. With this I was able to check the fuel line cross over. After about a gallon of gas running through the system with alternating petcocks open and closed… I felt that the flow was better. So, I put everything together and was going to ride over to MotorWest (An airhead shop here in Milwaukee) to pick up those fuel bowl gaskets. On the ride over there the Motorcycle felt reborn! Total power through the entire power ban… I’m not sure if I had an air pocket in the cross over line or a piece of debris… the bucket I was using to collect the gas was free of any debris. It is a complete mystery to me… and that is why I am worried.

I do think I am going to have to take the petcocks off and rebuild them for safe measures… but I am still at a loss…
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Old 03-26-2012, 07:52 PM   #26
Wirespokes
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Yeah, that's scary. The problem isn't resolved, you can bet on it! And it'll resurface!

Pull both petcocks and clean them up. If they're not leaking, you most likely won't need any parts. I polish the working face of the handle where the direction holes are located. That's the face that seals against the rubber gasket. I'll sand it with fine wet/dry, then polish on the polishing wheel.

I'll bet there's some corrosion in the petcocks or the screens are getting plugged. Then again, it might be the tank vent in the gas cap.

When you've found the problem, you'll know you're looking at the source! The odd problems are when there are two or three things going on to cause the same problem. You're sure the problem is fixed, but then it isn't...??? Find the second problem and it's FIXED! Yay! uh... no it isn't...
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Old 03-27-2012, 12:07 AM   #27
Bill Harris
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The odd problems are when there are two or three things going on to cause the same problem. You're sure the problem is fixed, but then it isn't...??? Find the second problem and it's FIXED! Yay! uh... no it isn't...
Yep, think of it as a row of dominoes... fix one, then...
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Old 03-27-2012, 07:28 AM   #28
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Thanks for the guidance! Lucky for me the weather is not that great this week, so it will give me plenty of time to pull the tank and give the petcocks some love.
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