1982 gs 650

[82GS650G]

So I have a pretty clean 82 GS 650, Just bought it a couple months ago and finally got enough money to put into the bike. It sat for 2 years not running, The last owner said it died on him mid ride!? I got a new battery and cleaned out the carbs to see if it will still fire, and it does!!! that's the good news... the bad news is its rev is somewhere in the 4,000 rpm spot at idle. It's air box has been deleted by a previous owner and it has an aftermarket exhaust, I believe that the jets have been tuned for this and there is a video of it running with these mods on Youtube. So i know at one point the bike has worked well with these mods. Here's a list of what i think might be wrong i'd love some input.

- Throttle cable is either caught, snagged or reinstalled improperly (by me)
- Carbs are not synced properly (Butterfly not adjusted yet I loosened main adjustment screw completely)(Carbs are Mikuni BS32SS CV's)
-Choke is stuck open or faulty
- Vacuum leak
- Regulator is has a busted diode (I checked with a multi meter but i don't know if that is a possible reason for over rev?)
- I'm using 92 unleaded fuel which might be too rich for the bike (although the Clymber manual says it can take 92 octane)
-This is my first real bike build and i'm doing something wrong???

Thanks For taking the time

 

[Big T]

Well, that's a good list. Let's eliminate two things:

Choke - these carbs have an enrichener circuit. Not a choke. If you see all four levers going up and down, it's not your issue.

Fuel - premium fuel is not richer, it just has more knock resistance (octane). Fuel grade makes no difference

High idle generally points to vacuum leaks, but the cable could be the issue. Start there

How are your intake boots? Soft?
When you cleaned your carbs, did you follow the tutorial?
Did you replace the O rings in the carbs and intake boots?

 

[steve murdoch]

Welcome to the site.
At least without the stock airbox the carbs are easy to remove for a proper cleaning.
Here is a detailed tutorial.
http://zeus.mtsac.edu/~cliff/storage/gs/Mikuni_BS-CV_Carburetor_Rebuild_Tutorial.pdf

When you have them apart be sure to document what the jet sizes are to check against stock.

 

[82GS650G]

That carb tutorial had some really great tricks for the next time i take them apart thanks for a great resource.

 

[82GS650G]

I played around with the throttle cable a little and it seems to have lowered down to about 2000 rpm! I didn't look at the intake boots well enough when i took the carbs off, but those haven't been replaced in at least five years so i'm sure i should probably just do that to be on the safe side. It still sounds a little bit rough and i will need to do some fine tuning as far as jet's and idle goes.