Bike has no power

[Phil Owen]

Bike is a 2000 I/S and due to my health has sat in the garage for all of this year.  I did push it out and start it some but the last 4 month it has not been started.   I pumped all the old gas that I could get out of the tank and put in fresh gas along with some carb cleaner and put in a new battery.  Bike initially very hard to get started and ran very rough for several minutes.  It now starts easy and idles smooth but I have no power when rolling on the throttle.  At max throttle I get between 3000-3500 rpms, and the engine surges some with the rpms staying between 3000 & 3500.  Bike does not have enough power to even pull forward into the garage and when I do try I get a hard engine knock.  the knock is not there when idling and just pulling back the throttle.  Just before I had to park it for a while I had the oil, air and oil filter changed along with the coolant.  Bike ran fine when it was parked.  As soon as it cools off I am going top pull a few plugs and look at them but since it idles fine and does not miss or shake like it is hitting on less than 6 I suspect the plugs are fine. 

Anyone got any helpful suggestions?  btw. This is the first time in 9 years the bike has failed to start and run 100%. 

[Patrick]

It sounds like you may have two problems..Both fuel related.. If you have the factory petcock then it may need servicing or the vacuum line may be cracked causing it to not allow enough fuel flow.. The other sounds like the typical carburetor varnish which occurs when the bike sits for a long period without adding any fuel additives..

[Thunderbolt]

If you have the parts laying around, build yourself an auxilliary fuel tank from and old lawn mower tank or similar.  Put a fuel cut-off in line.  Take your fuel tank off and use this setup to determine if your petcock is defective.  If it runs off this setup, then put a rebuild kit in the petcock.  I would also run more fuel conditioner through it.  When I had a jet obstruction, I used 1/2 gasoline and 1/2 Sea Foam in that external tank.  It smoked a little, but after letting it sit for a few days with this mixture in the carbs, the problem was corrected.

[Phil Owen]

The petcock is still factory.  I've added a little more carb cleaner and let the bike idle for 1/2 hour to get the mixture into the carbs. This seemed to cause the engine to run  a lot rougher after I added the cleaner.  There is a half tank of gas I added enough cleaner to treat about 5-6 gallons.  Is it possible to add to much carb cleaner?  I'll let this sit in the carbs for a day or so then add more fresh fuel to the tank.

I did try turning the petcock to off and the bike never ran out of fuel.  This would seem to indicate a petcock problem.

[Tropic traveler]

Yep, you have a non-functioning petcock.
The bad petcock will only cause a problem if any one carb gets a float stuck open. Otherwise you will just have no reserve.
It could be plugged and causing a fuel starvation problem as has been mentioned. I think it's time to have a thorough look at the whole fuel system from tank to carbs. 

[Phil Owen]

To check the petcock does the tank have to be removed?  I managed to hurt my back again today (the reason I have not been riding) and pulling the tank is not that easy for me anymore. 

[humshark]

Phil - if you need help - let us know where you are at and it is possible that someone will offer to come over and lend a hand if they are close.

[Patrick]

One thing I didn't think about [and should have] is critters.. I don't know if you live in an area where the little  'critters' try to find warm cozy places to spend the winter.. It might be worth the trouble to check the air box..