81 gs650g won't go above 35mph

[Guest]

so my 81 gs650g won't go above 35mph, and when i tried, it died and left me stranded at a gas station for 40 minutes or so. after about 40 minutes i got her to start up and get home. having to wait that long tells me that it isn't fuel, that it's something to do with the coils. after i brought i home yesterday i went through and cleaned the carbs since it supposedly had a stuck float and the PO couldn't get it to go above 35mph either. got it all put back together and went for about a 45min ride before she left me to sit at that gas station. when it died, there was no popping, just like i had hit the kill switch. i couldn't even get it to roll start. she wanted to kick over, but just couldn't until i waited long enough

[spchips]

Did you check for spark on all 4 cylinders? Did you look at the plugs, and what did they tell you?

Does it have the factory airbox, pods, or nothing?
If nothing was it re-jetted to compensate?
When, if ever, did it last run right for you?

This bike will not run right without an airbox.

Finally, in approximate order of importance, have you:

Cleaned the air filter
Changed the oil
Adjusted the valves
Cleaned the fuel tank of rust
Cleaned the petcock
Dipped and thoroughly cleaned the carbs
Replaced the intake boots and or checked for vacuum leaks

[Nessism]

What mods on the bike (exhaust, carbs, air filters, ignition, etc).

[Steve]

OK, you already were told it wouldn't go over 35. What did you do to fix it?

You were pointed to BassCliff's site in your only other post (so far), have you gone through any of that yet?

You bike is 33 years old. You KNOW it had problems when you bought it. If you haven't done anything, don't expect it to miraculously heal itself, you need to help it along.

Among the items that you will need to address will be valve adjustment, carb cleaning, brake inspection, tire inspection/replacement and electrical connection cleaning. Until each and EVERY ONE of those items is addressed, that bike has no business heading out of the garage.

.

[60ratrod]

The bike has 0 engine mods. the only thing the PO change was he put some café style bars on it. second, since he said it was acting as though it was fuel starved, like a stuck float, I went through and cleaned the bs32 carbs before trying to ride it. and I haven't seen the other post yet, so I will look there tomorrow. I checked the tank, and it has 0 rust inside it. the only things I haven't done is adjust the valves or cleaned all of the connections. And it does have spark on all 4.

[tom203]

"....I went through and cleaned the bs32 carbs before trying to ride it. "

You forgot to tell us how easy the carbs came off and on ! How about a pic of the bike to humor us?
Since it eventually restarted, unlikely electrical (unless it was helped with jump), so probably fuel delivery related.

[spchips]

Is the airbox on it?

[60ratrod]

I'll get photos up in a few. it's really a good looking bike. My main concern is that it shut off while I was riding like I hit the kill switch and had to wait at a gas station for 40 minutes before it started again

[850 Combat]

It matters if the airbox is on it. It matters if you removed and dismantled the carburetors and how you cleaned them internally.

[JTGS850GL]

Did you check for spark when it wouldn't start at the gas station? If you did and had a nice blue spark then it's probably not electrical.

Do the valves now before you cause more damage. This is not optional. You'd be surprised at what problems tight valves will cause.

Can it rev freely to over 5K RPMs when in neutral? Can you run it through the gears above 35 MPH on the center stand?

I wouldn't ride it until you've figured out what's wrong or you could end up with a bigger problem.

[60ratrod]

the airbox is on. i removed the diaphragm covers, diaphragms and needle assemblies, the float bowls, floats, needles, main jets, pilot jets, and needle jets. i then went and sprayed carb cleaner through all passages both ways, through both ends of the pilot and main jets, and then 30lbs of compressed air through the passages in both directions of the passage to make sure they were clean and free. and i would have checked for spark if i hadn't left the tool kit at the house. i can freely rev in neutral, but i will need to check to see where it stops revving

[tom203]

So air box on-decent filter element in?- did you have to remove covers over idle air mixture screws on each carb or had a PO beat you to it ?

[60ratrod]

Yeah, the covers were already gone. I didn't remove the mix screws. those were the only things I didn't remove when I cleaned the carbs. and the air filter was good.

[JTGS850GL]

Just a heads up, you didn't really do a proper cleaning if they weren't completely disassembled and dipped. Those pilot screws are very important and must be removed for the cleaning. O-rings must be replaced as well including the small one at the end of the pilot screw. Make sure you don't loose the tiny washer between the spring and the o-ring.

[tom203]

Yeah, it's impossible to clean slow speed circuit without removing those mixture screws. They are critical as engine transitions to mid range - your bike needs them!