my gs1100 won't start

[Anonymous]

Hi guys, I've got a 1982 GS1100G and I can't get it to start. The bike will just crank and no fire/sputter anything whatsover. I'll try to describe what I know as much as possible and hopefully that will get me started in the right direction. The bike has around 49,000 miles on it, it was running by the previous owner I think last summer. It's got gasoline in the tank (probably old) and I just added a couple gallons of fresh gas to it. It has spark to all four sparkplugs. I'm not sure what kind of spark to expect but it crosses the gap in each plug no problem. The petcock is turned to on. The guy I bought it from is not the same guy who had it running last summer, he is a mechanic and all I know is that he told me that he cleaned the carbs and adjusted the (jets, pilots?)because they were apparently set too lean. He seems like an honest guy and seems to know his way around engines. And although I haven't confirmed it for myself yet he says compression is good on the bike.

What gives here? How can I get this bike to start?

Thanks in advance.. Isaac

[habsdoc]

Sounds like you are not getting any gas to the plugs. Are they wet at all??? A little gas into a couple of cylinders and then try cranking it over again. Don't over do the amount of gas you pour into the cylinder or you may get hyrdraulic lock which can do some damage. I use a piece of fuel line so I don't spill all over.

Randy

[Anonymous]

You may not be getting enough vacuum to get gas to the carbs. The petcock operates on vacuum in the 'on' position. Set it to prime.

[Anonymous]

If your bike is like my 1982 GS1100G, which sat for 10 years before I bought it, probably your petcock need to be removed, disassembled and cleaned. When you take it apart, don't forget to pull the cap off the filter tower and run a small, stiff wire through to purge the silt, then use carb cleaner in a spray can to blow out the remains. Also, make certain the diaphragm has no pin-holes or failings. You need good vacumn to open the fuel flow on cranking.

[earlfor]

I wouold turn the petcock to prime, wait 30 seconds for the float bowls to fill and then turn the petcock back to run. Then, I would unscrew the float bowl drain plugs and drain the fuel into a small container, repeating this for each carb to check that all bowls are getting fuel and all are getting the same amount of fuel. If they are ok, Thenafter reinstalling the drain plugs, I would again turn the petcock to prime, wait 30 seconds for the bowls to refill, turn the petcock back to run and try starting the bike.

Earl

You may not be getting enough vacuum to get gas to the carbs. The petcock operates on vacuum in the 'on' position. Set it to prime.

[Anonymous]

Well thanks everyone for the advise... with your help I did finally get it to start, but it's really not running well at all and I can barely get it to start (with the help of starting fluid down the cylinders). It seems like maybe it's not getting enough fuel to the cylinders, but I'll describe the details. Basically I can get it to start by spraying eather down the spark plug holes and it will start and eventually idle, but will eventually stall out, especially if I try to give it any throttle. A couple of times I got it to start without eather using the choke on but it would only run with the choke on, otherwise it would die. I managed to take it for a brief test run and it felt like it had no power, while accelerating it would bog down and not get up and I had to keep letting off the power for it to pick back up again. Eventually it died at the bottom of a hill and I ended up pushing it back up the hill to my house. At this point it would only start and run with the choke wide open, and it would just die if I tried to let out the clutch and start driving. Tomorrow I guess I'll take a look at the petcock to see if fuel is flowing properly, but I'm not sure what to begin looking for as far as the carbs and vacuum, etc that people posted about. I did drain the bowels as earl suggested and fiddled with the prime but it doesn't seem to make a noticeable difference to starting and running the bike. Sorry about the length of this post guys and thanks for all the help!

[Anonymous]

Sounds to me like your carbs are out of sync. How long are you allowing it to warm up?

Also I remember reading something about starting fluid and motorcycles, I dont remember exactly what the messege read but I do remember that it was bad and its best not to use any. (shrug) Shouldnt have to.

When you go to start the bike if its cold then go ahead and have the choke full on. after a while the engine should begin to rev and you should be able to lower the choke. You may have yo play with the choke to find a sweet spot. Try not to use starting fluid, use it if all else fails I guess.

Justin

[Anonymous]

Is the spark a nice BLUE spark? How wet are the plugs? You might want to check your compression.

[Jethro]

IMHO, you gotta take those carbs off and go through 'em. Get a gallon of carb dip, cans of compressed air (or an air compressor), an o-ring kit from Robert Barr, and go to town on them. Also, rebuild the petcock, and take the gas cap apart and check that it's vent is free. Make sure your fuel line is good, the air filter is clean, and the intake tubes are sealing well. Throw some new plugs in there and see where you're at.

[Anonymous]

I had the same problem with my 550, I just totally dismantled the carbs cleaned them , replaced the rubbers, cleaned the jets and put them back together, and now it runs great.

[cbxchris]

Tell tell sign of only running with choke on is pilot jets are stopped up. Best do a complete carb clean and make sure your carb boots are good with no cracks. AND FRESH GAS.