Happy and confused.... the bike fixed itself

[simonp]

I'ce been going through the usual suspects trying to resurrect this 82 GS850GLZ that I rescued from a coworker's garage.

So far I've done:

new airbox boots
new intake boots and O rings
Valve adjustment w/realgaskets
new petcock
re-seal airbox
new spark plug caps
all fluids and oil changed, cables adjusted, etc

Carb sync with the cheap z1 gauges.
colortune

After all of this it still ran like crap, crappy idle, sputtering and spat noises when I revved it a little bit. I decided that I just HAD to ride it a little bit on Saturday, so took it down to the gas station. It did OK, sputtering as it was, so I took it out for a bit longer ride. I got it out on a straight country road and wound it up to 8K RPM a couple of times.

At the end of the road the idle had gone up to 2K. I adjusted it down and rode on. And low and behold all the sputtering was GONE. The bike fixed itself, but how? Did I just blow out enough carbon that it would have so seriously affected the engine?

I put 100 miles on that bike the next day

[BassCliff]

Ride for health!

Mr. simonp,

I don't suspect any "carbon" blowing out helped you. These classic bikes just like to be ridden. Any little amount of old gas that has varnished itself to the inside of the carb workings can cause it to run rough. By taking it out for a nice long ride you probably cleaned out some gunk in the smaller nooks and crannies of the carburetors. Perhaps dumping about a half can (6-8oz) of Sea Foam in a tank of gas and running it through will make it go even better.

Sometimes a little gunk will lodge in your main jets or other places. When you rebuilt your carbs, did you dip them for a few hours (some say overnight)? Sometimes that's the only way to get all the old, sticky gas out of all the nooks and crannies. A quick little half hour bath in the carb cleaner doesn't really get it all out.

Anyway, I'm glad it's running better. Try the Sea Foam and if you're good, you're good. I'm not looking forward to tearing into my carbs, but I know I'll have to someday.

Thank you for your indulgence,

BassCliff

[simonp]

It may be that the carbs weren't dipped. I didn't do it. They were very clean when I got them from a PO's attempts to get it running, although I sprayed them out again several times.

The next step for me is to replace all the needle valves and seats, and re-check the float heights. The kit the PO's mechanic put in has some seriously weak springs on the needle valves. It makes setting the float height accurately impossible.

I'll try the seafoam too. Thanks for the tips.

--Chris

[Pharkmeh]

Gratz m8 - gr8 bikes huh...

I left my old Suzi for a month under our open carport while I went interstate for work...

Came home, charged the battery and it was running on 3 cyls - messed with plugs n leads (limit of my mech knowledge)... in the end I just rode her back firing like buggery for a few miles - shut her down for the time it took to have a smoke....

Fired it up and she ran good as new.... shoulda noticed the few drips of water dropping to the ground..... either condensation or weather....

All it needed was clean fuel and away she went....

cheers

Phark