I am out of favor with the motorcycle gods - Page 2

HRCNICK11 · 11-20-2008, 08:15 PM

Whats wrong with the SV650 Tank? I have one and know them well. The petcock and pump are both vacume operated. One might have a bad diaphragm. The petcock can be checked with a vacume bleeder. The pump looks like a old style snowmobile pump. and is mounted to the frame near the airbox follow the lines you can't miss it. You might have just have a hole in one of the vacume lines, or it may have came unhoked.

Also gas these days has a lot of ethanol in it. Upto 10% its bad for metal and rubber parts and also clogs jets a lot faster. I have been draining my dirt bike tanks and carbs this year because the pilots have been cloging after about 2 weeks in the garage. Its easier just to drain the darn things.

unknownroad · 11-20-2008, 11:50 PM

I'm guessing the SV either has a bad petcock or something clogging the pickup. It'll start (after a lot of cranking) and idle okay, but as soon as you crack the throttle it dies. The problems went away when I tried running the bike off my riding mower gastank, so it's gotta be somewhere in there. I tried applying some suction to the vacuum side of the petcock and it seemed to drain okay, but there's gotta be some kind of flow restriction...

I'd be happy to unload the GPz, but it's really just a parts bike... Looks like a decent naked project until you get close...

HRCNICK11 · 11-21-2008, 06:50 PM

I bet its the pump was the vac line connected to the pump. Might even be hooked up backward if someones been messing with it.

HRCNICK11 · 11-21-2008, 06:52 PM

I don't think this is your problem but there is also a screen under the float needle seat. Thats for future referance only cause it ran off the other tank. Might just be crappy old gas in the bike tank.

unknownroad · 11-21-2008, 07:23 PM

Nah, it wasn't messed with until after it refused to start and I started poking around... I've owned the bike since it was new, and it's only been worked on by other people twice.

Oh yeah- what's the hose at the rear of the tank for? I forgot to mention, it was disconnected when I first looked, must have come undone from having the tank up for something else.

unknownroad · 01-08-2009, 02:40 PM

UPDATE:

13 motorcycle frames, 13 engines, 26 wheels
8 vehicles complete enough to be immediately recognizable as motorcycles
6 of them are titled
3 of them are registered/insured

AND STILL NONE OF THEM RUN!!!

For one beautiful day last week I had one bike that ran long enough to take me to work and back. Filled it up on the way home, parked, and smelled gas. Then I saw gas. Dripping. Fast.

Seam failed at the back of the gas tank

Meanwhile, I determined that the petcock on my SV was not functioning properly, but not until after applying way more vacuum than you're actually supposed to use on it. Which probably broke it. So, the new $60 petcock that I waited two weeks to get from an online parts dealer did me no good, and now I've got the carbs sitting on the workbench, next to three sets of CX500 carbs that have already been taken apart.

Edit to add- you really don't expect to see this on a bike that's never sat for more than two months at a time...

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11-20-2008, 08:15 PM	#11
HRCNICK11 Canyon Carver Join Date: Nov 2008 Posts: 429	Whats wrong with the SV650 Tank? I have one and know them well. The petcock and pump are both vacume operated. One might have a bad diaphragm. The petcock can be checked with a vacume bleeder. The pump looks like a old style snowmobile pump. and is mounted to the frame near the airbox follow the lines you can't miss it. You might have just have a hole in one of the vacume lines, or it may have came unhoked. Also gas these days has a lot of ethanol in it. Upto 10% its bad for metal and rubber parts and also clogs jets a lot faster. I have been draining my dirt bike tanks and carbs this year because the pilots have been cloging after about 2 weeks in the garage. Its easier just to drain the darn things.

11-20-2008, 11:50 PM	#12
unknownroad Guys... where are we? Join Date: Nov 2008 Location: South Carolina Moto: SV650 Interstate, CX500 rat-bobber, whatever else runs. Posts: 784	I'm guessing the SV either has a bad petcock or something clogging the pickup. It'll start (after a lot of cranking) and idle okay, but as soon as you crack the throttle it dies. The problems went away when I tried running the bike off my riding mower gastank, so it's gotta be somewhere in there. I tried applying some suction to the vacuum side of the petcock and it seemed to drain okay, but there's gotta be some kind of flow restriction... I'd be happy to unload the GPz, but it's really just a parts bike... Looks like a decent naked project until you get close...

11-21-2008, 06:50 PM	#13
HRCNICK11 Canyon Carver Join Date: Nov 2008 Posts: 429	I bet its the pump was the vac line connected to the pump. Might even be hooked up backward if someones been messing with it.

11-21-2008, 06:52 PM	#14
HRCNICK11 Canyon Carver Join Date: Nov 2008 Posts: 429	I don't think this is your problem but there is also a screen under the float needle seat. Thats for future referance only cause it ran off the other tank. Might just be crappy old gas in the bike tank.

11-21-2008, 07:23 PM	#15
unknownroad Guys... where are we? Join Date: Nov 2008 Location: South Carolina Moto: SV650 Interstate, CX500 rat-bobber, whatever else runs. Posts: 784	Nah, it wasn't messed with until after it refused to start and I started poking around... I've owned the bike since it was new, and it's only been worked on by other people twice. Oh yeah- what's the hose at the rear of the tank for? I forgot to mention, it was disconnected when I first looked, must have come undone from having the tank up for something else.