Marbling the 1600

[dogdoc]

Hey Guys: has anybody who owns a 1600 did the marble trick? if so where in the heck is the tube to insert 1-2 marbles? I printed off the diagrams from gadgets page but not real clear. Where do I look exactly to find the correct tube? BlownDodge its your chance to shine, again?? thx Guys. Does it work?

Doc

[blowndodge]

If you look under the right side cover you will see a black tube coming in behind the right hand side fast idle solenoid at about the two o'clock position, about an inch and a half long. The tube will allow about the size of your little finger tip to enter. Put a 1/2 inch marble in the hole.

[rflnomad]

I have heard of this. But I am still not sure of why it is being done. My bike is stock except for a gutted goat bladder ( see gadgets page ) and seems to run fine.
its a 05 with 5K miles. All ways use Hi-Test fuel too.

[beezer]

Is this to reduce pinging?
My bike whistles and I have no clue what that is.

[blowndodge]

This modification is done usually when aftermarket exhausts are installed. That hose is there for emissions. What happens is air is drawn into that tube and that tube goes to the exhaust manifold and the extra air helps further burn any residual emissions from unburnt fuel.

With the stock exhaust so plugged up you don't hear the backfiring that is going on because of this. With an aftermarket open exhaust you will really hear how bad it is. "Marbeling" blocks this extra air injected into the exhaust manifold so the backfiring you would hear with open exhaust is substantially reduced. It does nothing for pinging.

[beezer]

Thanks for the explanation BD. On my last bike (C50) I disabled the pair valve with 2 golf tees.

[blowndodge]

Is this to reduce pinging?
My bike whistles and I have no clue what that is.

What tune is it whistling? It's probably the gas cap

[beezer]

[quote:ibbmleru]Is this to reduce pinging?
My bike whistles and I have no clue what that is.

What tune is it whistling? It's probably the gas cap[/quote:ibbmleru]

High pitch. It gets louder or quieter with more or less speed.

[dogdoc]

Thx BD I knew i could count on a tecnical but simple answer. I will try it this weekend. yes my gas cap whistles Dixie but I love it.

[flightdoc]

I've never heard my gas cap whistle at speed. It may be the induction ( throttle bodies) sucking in air. I'm no expert. Just a guess.

[blowndodge]

It is a sort of simple fix. Mine was so bad that it whistled for 10 minutes after riding and/or when I opened the tank to put fuel in, it was under so much pressure that it opened like a shook up can of beer. It was awful until I took apart the cap and removed the blockage that covers the "normal" vent hole that all bikes use to use. I guess its another air quality thing that is pretty dumb by design. No whistle and no pressure build up. Plus, now I can fill my tank all the way with so leaking around the cap.

[dogdoc]

Didn't mean mine whistles at speed, only when hot out and near full tank. Its designed to purge pressure. Doesn't bother me anymore.

[blowndodge]

If it whistles though there is too much pressure. The mechanism inside the cap is machined poorly and the parts that are supposed to "slide" open as pressure builds in the tank don't always slide open and high pressure, leaking from the tank when near full, gas coming from the overflow spilling on the ground below your bike. If you have nothing but sound and thats it that it hasn't got worse. Mine was awful...

[dogdoc]

Mine just whistles no gas spillage BD, but thx anyway.

Same with my gas tank. I call it my teapot. I also have a whistle like Beezer is talking about. Don't hear it at idle. I hear it when I'm increasing speed or shifting down. I've pretty much gotten used to it.