J
joseleary
Guest
I have a 1982 GS850gl that was running, but very slowly. I got lots of good advice from you fine folks here at GSR and began taking the necessary steps to correct it. I got tons of great info, especially the carb rebuild pics. I ordered a set of new intake boots and an o-ring kit from Robert Barr (thanks! a total life saver). I got my workbench cleared off, got out my wife's camera and began to slowly and methodically rebuild my carbs. It was great. I love being in my garage. I was really enjoying it UNTIL ... I got to the mixture screw on carb #2.
The guy I bought it from (2nd owner) told me that it had been sitting for many years (inside thankfully) when he got it. He brought it to a bike shop and had the carbs "done". Looking at the gouged out screw slot on the #2 mixture screw I was reminded of the part in Zen and the Art of Motorcycle Maintenance where he makes the mistake of going to the shop and has his bike screwed up by careless mechanics.
At first I tried to use the right sized screwdriver and some PB Blaster to get it out but there was not enough left to grab. Next, and this is very dumb, I got out my drill and an extractor bit. I've never had much luck with these and only now do I know why. I used my punch to mark the center of the screw and drilled out a small hole. Next, I put in the extractor, set my drill in reverse and SNAP! a small set back just turned into a huge problem that might only be solved with dynamite! Extractors are made from hardened steel that is very brittle and impossible to drill through. Once you've got a piece of one stuck somewhere the only way I know to get it out is to drill away the surrounding metal. I was reluctant to jump right into this task because this is a sure way to ruin the threads of what ever you are drilling the screw out of. I did a little research, first here, then at Dan's motorcycle repair. His sight is great! ( http://www.dansmc.com/index.htm ) I read about the old crazy glue on the end of a bolt trick and tried it with no luck. Next I learned Dan's technique for using extractors, instead of using the drill he traps them in with a hammer then turns them by hand. Sure wish I had a time machine.
Anyway, after striking out with the crazy glue, I said a prayer and started drilling away the screw. After lots and lots of drilling I finally got the little piece of the extractor out and drilled out the mixture screw. The threads in the carb body were wrecked but I suspect they were crossed to begin with. To fix this I got a tap and die kit. Unfortunately the threads on the mixture screw are 6mm x 0.5 pitch. This not a very common size tap and I had to special order one.
My plan for when it gets here is to coat the old threads with a thin layer of JB Weld, drill it out and cut threads with my new tap. If this works I will let you all Know. If not I'll be buying a new #2 carb body.
I wonder if this is how Captain Ahab felt?
The guy I bought it from (2nd owner) told me that it had been sitting for many years (inside thankfully) when he got it. He brought it to a bike shop and had the carbs "done". Looking at the gouged out screw slot on the #2 mixture screw I was reminded of the part in Zen and the Art of Motorcycle Maintenance where he makes the mistake of going to the shop and has his bike screwed up by careless mechanics.
At first I tried to use the right sized screwdriver and some PB Blaster to get it out but there was not enough left to grab. Next, and this is very dumb, I got out my drill and an extractor bit. I've never had much luck with these and only now do I know why. I used my punch to mark the center of the screw and drilled out a small hole. Next, I put in the extractor, set my drill in reverse and SNAP! a small set back just turned into a huge problem that might only be solved with dynamite! Extractors are made from hardened steel that is very brittle and impossible to drill through. Once you've got a piece of one stuck somewhere the only way I know to get it out is to drill away the surrounding metal. I was reluctant to jump right into this task because this is a sure way to ruin the threads of what ever you are drilling the screw out of. I did a little research, first here, then at Dan's motorcycle repair. His sight is great! ( http://www.dansmc.com/index.htm ) I read about the old crazy glue on the end of a bolt trick and tried it with no luck. Next I learned Dan's technique for using extractors, instead of using the drill he traps them in with a hammer then turns them by hand. Sure wish I had a time machine.
Anyway, after striking out with the crazy glue, I said a prayer and started drilling away the screw. After lots and lots of drilling I finally got the little piece of the extractor out and drilled out the mixture screw. The threads in the carb body were wrecked but I suspect they were crossed to begin with. To fix this I got a tap and die kit. Unfortunately the threads on the mixture screw are 6mm x 0.5 pitch. This not a very common size tap and I had to special order one.
My plan for when it gets here is to coat the old threads with a thin layer of JB Weld, drill it out and cut threads with my new tap. If this works I will let you all Know. If not I'll be buying a new #2 carb body.
I wonder if this is how Captain Ahab felt?
I've read where you can also try the freeze spray on the screw, kinda doing the same as adding heat to the body, to break the bond and make it easier to turn.
