GS 450 not revving over 5500rpm

[Guest]

Hello there I just bought my first bike in over 6 years, becouse i really want to do an cafe racer project. The bike is an 1983 GS 450E. The bike has been sittin for over 6 years , so i got it quite cheap. First thing i did was to clean the carbs. They had had some gunk in them with i removed an cleaned all the jets. After the first start the bike revved only to 2000 and then stalled. With the choke on a bit higher revs were achieved. Took the carbs of again and cleaned them again. Now it revves to 5500 (ish)and starts to backfire and shutter. I have a new good battery and new fuel. What else is there that could cause this?

[tkent02]

Let me guess, you removed the airbox?

[Bajare80]

Yes and no. I first had the air box of, but then put it back. No change. Should have mentioned that

[tkent02]

OK, the not winding out thing is very common for CV carbs with no airbox.

[Bajare80]

I just measured the the battery. It only gets 12.5 volts when revving. And i found a black/yellow wire hanging loose.

[tkent02]

Find any post by member posplayr, he's the expert on this electrical stuff. In his signature you will find the links to his stator and charging system tests.

[Bajare80]

Man what a Cluster Fack. Went to check the stator with a multitmeter. Only one pair of the 3 wires gave a reading for Ohms, and 1 wire gave connection from the ground. Well then i went to open the left hand side cover. The oil that was running out was very thin and smelled like fuel. Not good . Could it be that the gasoline like oil has eaten away the isolation from the stator? And anybody know where i can find a wiring diagram for my bike? (GS 450E -83) Thank you

[tkent02]

Slow down. Fix things one at a time. Sounds like the stator or at least the stator wiring needs some work, were the other two legs open or shorted? Check the wiring and check the connectors, the connectors all need to be cleaned up anyway after decades of neglect. Resistance due to corrosion causes all kinds of electrical problems.

Gas in the oil is very common with a leaky petcock, or if it was left on Prime for a while. I don't know if the gas in the oil can hurt the stator, haven't heard of it but who knows? You probably don't know how long the gasoline was in there, but fix the petcock or at least disconnect the fuel line when it's parked. Otherwise you may change the oil and fill it with gasoline again.

Wiring diagram and service manuals can be found here:

http://members.dslextreme.com/users/bikecliff/

Basscliff put a great resource together. His site shows the very long list of things that should be maintained before putting a bike that's been sitting for years back in service.

[Bajare80]

Just to many things going wrong in one day But the wiring diagram is a big help. Thank you.

[mrbill5491]

Yes and no. I first had the air box of, but then put it back. No change. Should have mentioned that

Uh, did you have the air filter in it?

[Bajare80]

Uh, did you have the air filter in it?

Yes i did. Not a new one but it did not have any bird nests or dead cats in it. Same problem without the airbox.

[smilinbrad]

I had a lot of fuel in my crank case when I bought my 400 and my 450 (sitting for who knows how many years). Turns out I had a few pin holes in one of the floats. The float sunk, the gas flowed into the engine and past the rings into the crank case. Rebuilt the carbs, changed the oil, rebuilt the petcock, all is well now. I suspect the stator is your major problem although it will need a lot of attention to all the other issues. Just a note: I've cleaned (I thought) lots of carbs with solvent over the years. Last month I borrowed an ultra-sonic and now see I was just kidding my self with the solvent bath. Never again!