partial carb success

[1980gs1100l]

Ok i know you guys are probably getting tired of me asking my dumb questions cause im lazy and dont want to tear the carb down and do it right but thanks to everybodys help ive got my bike running the best she has since i got her from her po. My concern was she was cold natured originally, couldnt set the choke in a position where she would run on her own, all you could do was hold the throttle a bit til she shook her chills off. Then warm she ran good but knew it wasnt her full potential cause when you would back off the throttle she would pop out the exhaust. Everyone i talked to said she was prob a little lean and they were right not to mention my mains were a different size. I had 3 125's and 1 112.5. I had some extra jets that came with a carb kit so i drilled them out with a no.55 drill bit, cleaned the carb as best as possible without seperating the rack reinstalled and she runs like a stripped ass ape but still have some popping on decel but overall she runs the best she has since ive got her. Ill get all the bugs worked out eventually as time permits im pretty sure i need to shim the needles now but we are gonna have some bonding time first, just wanted to say thanks

[Steve]

Just out of curiosity, how did you determine that you needed a #55 drill bit?

Does anybody have any idea what number jet that is equivalent to?
Because you now have no idea what your jetting is, you will have LOTS of fun trying to fine-tune it.

If you can determine the approximate equivalent jet size, please do yourself (and any potential subsequent owners) a favor and put jets in there that have correct numbers on them. Imagine someone's surprise when they see #125 jets, decide they need a little more, so they put in #130 and can't imagine why it's now running lean, because your drill might have taken it out way past 130.

I am sorta glad that you admitted that you are "lazy and dont want to tear the carb down and do it right", because I was going to have to point it out. Two of the three very basic things that need to be done to these bikes to get them to run right are clean the carbs and adjust the valves. If the bike is hard to start, it might not be getting gas, so you need to clean the carbs properly. Merely removing the float bowl and spraying some carb cleaner around just will not do the job. If the carbs are clean and it still won't start, the valves likely need to be adjusted. Once these two items are addressed, your bike will start so easily, you will think it's a brand-new bike. In fact, there are times that my wife's '82 850L and my son's '81 850G start quicker than my 2000 Wing, which starts pretty darn quick (most of the time).

Bikes that are "cold-natured" are probably running a bit lean. One of the easiest ways to correct this is with the idle mixture adjust screw. The factory had to have them set rather lean to meet EPA regulations, but the bikes run so much better if they are richened up a bit.


Oh, yeah, the third thing these old bikes need is to have all the electrical connections cleaned.

.

[1980gs1100l]

ok to answer your question a no.56 drill bit is the same size as a 125 main so a no.55 is a bastard size basically my jets are between a 125 and 127.5 as far as just spraying carb cleaner around thats not the case i replaced needles/seats took a guitar string to every orfice had the carbs totally apart without seperating them so not to screw up the o-rings im not sure if its still gonna be cold natured or not today is the first time ive been back on it i just got it put back together so ill let ya know then as for a potential new owner i dont see that in her future anytime soon and i didnt adjust the mixture screws i was kind of anxious to see how she was gonna do that will be for the next rainy weekend

[Steve]

I applaud your creativity, but question your decision to not take it apart so as not to disturb the o-rings.
Those o-rings are probably the source of your problems and need to be replaced.

You can get all the o-rings in a kit from fellow GSR member Robert Barr at www.cycleorings.com. It's about $15 or so for the entire kit.

Also not sure about using a guitar string as a pick. It is likely harder than the brass jets and might scratch the insides, possibly changing the flow through the jet. I have found better luck with a single strand from a multi-strand copper wire. The copper will not scratch the brass, but is harder than any gunk that might be stuck in the hole.

Underneath each mixture screw is one of the smallest o-rings around, and it probably has the most effect on how the engine runs at low throttle openings. To change that o-ring, you will need to remove the mixture screw. If the screw has not been removed, there is a good chance that the passages below it might be dirty, too.

All of this just goes to show why we constantly beg all of you guys to please do it right. When it comes to carb cleaning, there are no shortcuts. If you try to do shortcuts, you will only end up pulling the carbs again and again, until you finally decide to do it right.

.

[hikermikem]

+1 on what Steve says...