1980 850GT New problems - don't know where to start

[Anonymous]

I've recently taken off my carbs and cleaned out my float bowls/needle/seat because of the bike flooding and not idling. I didn't notice any floats that were stuck or anything, but I cleaned all 4 and it seemed to fix the idle problem.

However, I tried riding it to make sure it was running okay, and I got about 3 miles and noticed a drop in power. After taking it onto the highway, the most speed I could get on it was up to 72 MPH and it kept getting worse from there as I drove it home.

I pulled the spark plug caps off while it was idling one at a time - 2 & 4 caps made no difference in the idle...1 & 3 killed the engine when they were pulled off.

I cleaned the plugs and took it back out for another ride and when i got it back 1 & 4 made no difference and 2 & 3 killed the engine.

Then I let it sit overnight. Tried again today - #4 made no difference - the other three killed the engine (or at elast drastically effected the idle speed.)

Okay, so I'm a little lost. I adjusted one of the float levels (#1 carb) and I've added a K&N air filter that fits the stock airbox, but other than that nothing has changed.

Where do I start? What do I look at first. Any ideas - I'm losing lots of riding days :x

--Dwight

[arveejay]

Without being there I can't say for sure about plugs not firing, did you open the drain at each carb to assure they are getting gas. As for the new air filter, I believe changing the air filter requires changing the jets to match it.

[Mobetter]

Ride on the highway at speed for several minutes,
look for a good stopping place and pull your clutch in, hit the kill switch, pull over and check the color of all of your plugs. All should be
tan to light gray in color.

Hint: take some feeler gauges with you. It's easy to drop a burning
hot spark plug and change the gap setting.
Peace
Mo

[Anonymous]

Sounds like something's not happy in one or more carbs. I would take the carbs back off, then take the bowls off, along with all four top caps and slides, needles. Remove main jets, pilots, and the needle jet. Needle jet needs tapped upwards (towards the top of carb). There's a bunch of little holes in the needle jet that get plugged almost as easily as pilots. I use a piece of wire from a wire brush to make sure all holes are clear. A can of carb cleaner with a little plastic spray tube works good for blowing through all the passages you can find, especially from the pilot out to the air jet on the air-box side of carbs. Then adjust the floats and pin it all back together. That might help. It doesn't take much crud to really screw up those Mikuni's! I'm still battling crud in my '80 GS850G after two cleanings. Time to work on the gas tank, I guess.
Good luck! It sucks losing riding time!

[Anonymous]

I haven't been able to work on it for the past couple of days. But I'll try the riding and check the color of the plugs today. Then, I'll go the next step if I don't see anything there and pull the carbs off and give them a little more thorough cleaning.

Thanks for the suggestions and I'll keep you updated.

[AOD]

carb o-rings gone bad?