No internal petcock on Ca-cycleworks tank?

Jdan · April 12, 2011, 11:19:54 PM

I bought the Ca-cycleworks tank for my carbed '00 750 and post installation I was running insanely rich. Fuel was constantly pouring out of my tank which fouled the spark plugs and nearly flooded my cylinders.
So I installed this little thing on my fuel line.

This is just a heads up if anyone planned on buying from them. Has anyone else had a similar problem?

Howie · April 13, 2011, 06:12:13 AM

Oem tanks don't have an internal petcock either. Your Monster had a vacuum operated fuel shut off mounted externaly at the tank hinge. Go here
http://www.ducatimonsterforum.org/index.php?topic=47262.0 and scroll down. You will see it. I have the same red petcock on mine.

Jdan · April 13, 2011, 07:47:52 PM

If the fuel shut off was externally mounted than why would changing a tank, while keeping all the tubes in the same configuration, affect the flow?

booger · April 13, 2011, 08:09:36 PM

You should ask Chris @ CA Cycleworks

ducpainter · April 13, 2011, 08:12:55 PM

Quote from: Wilco on April 13, 2011, 07:47:52 PM
If the fuel shut off was externally mounted than why would changing a tank, while keeping all the tubes in the same configuration, affect the flow?

That is a good question.

Rest assured that all Monsters have an external fuel shut off...there is a problem somewhere.

Jdan · April 13, 2011, 08:50:00 PM

Thanks for the replies.

But at 25k+ miles and the new petcock working just fine it doesn't seem like a huge deal.
Still, any ideas on a problem?

ducpainter · April 13, 2011, 08:56:08 PM

Quote from: Wilco on April 13, 2011, 08:50:00 PM
Thanks for the replies.

But at 25k+ miles and the new petcock working just fine it doesn't seem like a huge deal.
Still, any ideas on a problem?

The needle valves in the carbs should shut off the fuel before it gets into the cylinders and fills the cases...

unless it's entering the manifold through a vacuum line of a failed petcock.

Jdan · April 13, 2011, 09:00:32 PM

So apparently the restriction plates on the new tank are different to allow for a higher flow of fuel. This heightened flow might be enough to overwhelm the vacuum produced by the fuel off switch and cause a constant outpour of gas.

If this is true than my ghetto-ass petcock might be a necessary mod.

Howie · April 14, 2011, 03:29:45 AM

Good theory, you'll never know for sure. My guess is the vacuum shut off failed and was never replaced. Hardly a ghetto repair unless you are calling DP and myself ghetto.

ducpainter · April 14, 2011, 03:39:35 AM

There are no baffles in a stock tank.

I doubt there are any in the new tank.

The only difference might be the hole size of the outlet, and volume of the tank itself.

corey · April 14, 2011, 04:19:38 AM

more importantly, how about some pictures of the bike with the damn tank on it!

Jdan · April 14, 2011, 02:04:51 PM

QuoteMy guess is the vacuum shut off failed and was never replaced

Hmm. I'm not sure why exactly the vacuum petcock would fail, seeing as I swapped tanks within the same day. Nothing sat around for more than an hour or so. My only guess can be that the flanges on the new tank are larger.

QuoteThere are no baffles in a stock tank.

How about some sort of diaphragm?

Quotemore importantly, how about some pictures of the bike with the damn tank on it!

Here you go! [moto]
Sorry for the bad cell-phone quality pictures though.3

Jdan · April 14, 2011, 02:06:10 PM

Just some different shots.

Howie · April 14, 2011, 02:41:32 PM

Quote from: Wilco on April 14, 2011, 02:04:51 PM
Hmm. I'm not sure why exactly the vacuum petcock would fail, seeing as I swapped tanks within the same day. Nothing sat around for more than an hour or so. My only guess can be that the flanges on the new tank are larger.
How about some sort of diaphragm?

Was the vacuum shut off there? I was under the impression it was missing. Anyway, it could have failed years ago. No diaphragm, no baffles.

Here you go! [moto]
Sorry for the bad cell-phone quality pictures though.3

Jdan · April 14, 2011, 08:22:30 PM

QuoteWas the vacuum shut off there? I was under the impression it was missing. Anyway, it could have failed years ago. No diaphragm, no baffles.

Yes, the vacuum was always there. I'll get pics up tomorrow. If it failed years ago, then wouldn't the old tank have the same problem? When I took it to the shop (I've had this petcock installed for months now), the mechanic mentioned something about the new tank missing a diaphragm that the old one did in fact have. He offered two fixes; the more expensive fix being installing a new diaphragm for the new tank or the cheaper, manual petcock which I went with.

News:

No internal petcock on Ca-cycleworks tank?