help. 2,500 miles from Seattle. Stranded.

[GS-ESW]

I took off nov. 4th, on my 1980 GS 1100-E. He ran perfectly for 2,500 miles, then went weak around the california/ arizona border. I pulled over and changed my plugs. They were all 4 white, which was wierd, because they have always been a little rich. Th bike has always run rich for the three years, and 16,000 miles I've owned it. I turned the terrible little petcock to prime, and started it up. It ran the same. No change. The bike runs weak, and the header exhaust note sounds like it's not running on all four. All pipes are hot to the touch, and all plugs are identically white/lean. I chugged to a town called Needles. There were no cycle shops there. I chugged, barely able to go 65, the next 100 miles through the most desolate place I've ever seen. I made it to Ludlow at dusk on Sat. night. There were no cycle shops. I got up and drove 50 miles to Barstow Sun. morning, barely made it there. The bike doesn't want to go low rpm's, it will die. The city of Barstow has a cycle shop, that's closed Sun. and Mon. I'm waiting for them to open Tues. morning. I worked on this problem all I could, and I can't fix it. I have put a hose on the petcock's fuel line, took off the gas cap, and bleww backwards on prime. It bubbled through, so I figured it wasn't clogged. I have fresh plugs in it. All I can conclude is maybe my ignition brainbox has gone bad, or all four carbs are partially clogged. I'm either not getting enough gas, or the spark is really weak. Amazingly, it has run this way without dying for 150 miles. Any help would be much appreciated. Stuck in Barstow.

[81ZUKI75]

I would think that if you had "weak spark" that the plugs would indicate a rich condition, not lean.

Are you running the stock airbox or pods? In either case, have the filters been compromised...holes, loose, disconnected, etc that might cause leanness?

If I'm reading right, you checked the petcock for one flow direction, what about the other? Pull the fuel line off at the percock, put it on prime and make sure you get good flow.

Good luck....

[rustybronco]

Well Eric, a few things you can check are, the voltage going to the ignition coils and the resistances of the ignition coils. the voltage going to the coils should be at or near battery voltage. the coils resistances should be approximately 3 ohms on the primary side and around 25,000 ohms when measured from plug cap to plug cap, on both the 1-4 and 2-3 coils. the plug caps when measured by themselves should read approximately 5,000 ohms per each plug cap when removed from their respective plug wires then measured end to end. (one per each spark plug wire- four plug caps in total)

does your bike smell like its running rich? never mind the lean plug colour, excess fuel can wash the color from them.

[chef1366]

I would suspect the petcock first

[Planecrazy]

Try running the bike with the gas cap off and see if it runs normally... Could be that the gas cap vent has become blocked, and it is creating a vacuum in the tank that's starving the bike of fuel. If the bike runs properly with the cap off, you've found the problem...

Good luck!

[GS-ESW]

shop just told me engine is blown.

A compression check revealed 10 pounds on cylinder 2, and 50 pounds in cylinder 3. Wow. Last compression check showed 150 pounds all across all four , about four or five months ago. Repair will cost more than bike is worth. I will probably rent a truck/ van to carry the carcass back to Seattle, or sell it to the shop as junk, and trade it in on a used bike they have. Sad end either way. CRAP, just when my ride was going to be a warm coastal, enjoyable experience.

[rustybronco]

Have them check the valve clearances, adjust, then re-check the compression readings.

[Big T]

If it was running good, then suddenly went bad, I'd be suspect of those compression numbers

More likely carb or ignition problems

It sound like you sprung a major air leak

[tkent02]

Have them check the valve clearances, adjust, then re-check the compression readings.

Yes, this.
Unless you set the clearances yourself recently. Do NOT let them rebuild anything unless a compression check is still low after the valve adjustment and a 1000 miles or so running afterwards. If you adjust the valves and the compression comes up a little bit, but is still low, ride it! The valves will begin to seal again, the compression will come up. Then check the clearances again.
I have seen three GS engines this year alone with this problem, after the adjustment their compression come back up. After a bunch of miles, the compression came up a lot more, but the the clearances got tight again....
So much easier to do it right in the first place.
It takes a lot of effort to combat long neglect.

That shop wants your money.

[Billy Ricks]

RapidRay isn't too far down the road from you. Scott Horner has a shop in La Verne, CA and may be able to help as well. Scott goes way back with the GSR.

http://www.headsupturbos.com/contact.html

[craywm]

All I have to contribute is do everything you can to keep that bike running. Of course if theres a fix needed that costs more than the bike than scrap it.. But before you do, triple check EVERYTHING. If you can, do it yourself so you KNOW that everything has been tried. Good luck!