Wow! What a change.

[demark]

I've owned my 1980 GS1100 for almost exactly two years now. Just this weekend, I put my 4000th mile on her (24k, total). Up until a few months ago, she was very temperamental with starting/idleing. Lots of bucking and sputtering. I'd have give lots of choke for 5 or 10 minutes before I could ride. I could never get the idle down below 1500. When she did idle, her RPMs would surge.

Not being a mechanical guy by trade or hobby, I was reluctant to do anything beyond the basics (oil change, spark plugs, carb synching, etc) because I was afraid that I would do more harm than good.

Fate stepped in a few months ago. My chain was just too stretched to ride, which means I would (gasp!) have to work on her.

I took the opportunity to do a 530 conversion and change the ratio from 2.8 down to 2.6. Since I already was doing work, I decided to do a thorough cleaning of the carbs, which included overnight dips in "Gunk", and replace the o-rings. After cleaning and reassembling 3 of the 4 carbs, the last screw I had to remove from the final carb got stuck.

LESSON #1: While force might end up being the answer, when something gets stuck and you've been working all day, walk away for a little while and come back with a fresh set of eyes.

I ended up making a big mess of the air screw and had to hand it off to somebody else to try and extract it.

I bought another set of carbs off of ebay and went through the same procedure. When the last screw on the last body (again, the air screw) got stuck, I took heed of my lesson and walked away for a little while. When I came back, I used finesse instead of force and got the screw out lickety-split.

With the addition of some nice new stainless cap head bolts, the 20+ year old carbs looked pretty darn nice back on the bike. Although she needed a little extra cranking on the Start button, she fired right up.

All I can say now is WOW.

It is amazing how much better she rides now. I only need to give a little choke for her to start up and then take all but the smallest amount away for a few minutes while she warms up. Idle is nice and smooth - no bucking or surging. When she does warm up, she settles in right to 1100.

I was worried that the gear change would affect the ride. Not at all! She still has more than enough power to push me off the seat as she takes off. Cruising is a lot smoother as highway speeds are about 400-500 RPMs less than they use to be. Plus, my first full tank of gas came in at 48 MPG - about 6-8 MPG better than before.

She is still only running on a bench synch and highest RPM air screw setting - I'd like to get in there with my Carbtune and Colortune and really dial her in. The only problem left is that she still sounds like popcorn popping when deaccerating under load and I am hoping the final tuning will take care of that as I can't find anything wrong with the boots or exhaust path that might be contributing to that.

Anyway, consider me a convert. Everyone always seemed to be preaching "first thing, make sure those carbs are clean" when it came to tuning/maintenance, and now, so will I.

- Tony

PS - Just last week, I got my original carb back with the air screw extracted. The top of the screw needed to be milled because I busted it up so bad. The best part is that none of the threads were damaged, so, once I replace the screw, I'll have a "backup" set of carbs either to keep or sell.

 

[white_2003]

as far as the pop an decell good luck ive made several trip to my buddies dyno and got close but its running really good. especially if you have pods they run so lean on decell thats were the popping comes from im asuming it has something to do with the idle fuel curcuit being so small great for ideling not at 6000 plus RPM's IMO just makes sence

 

[TheCafeKid]

as far as the pop an decell good luck ive made several trip to my buddies dyno and got close but its running really good. especially if you have pods they run so lean on decell thats were the popping comes from im asuming it has something to do with the idle fuel curcuit being so small great for ideling not at 6000 plus RPM's IMO just makes sence

This is generally cured by stepping up one size in the bleeder jet and tuning of the pilot circuit. It takes quite a bit of patience but it can be tuned out of it. Or, another idea is to find a set of Mikunis off a GPZ1100 (the ones all the guys use when they rip the crappy fuel injection off of them) I cant remember the model, but they have both an accelerator pump and a DECELERATOR pump that gives a MINUTE mist of gas on decel to keep the bike from leaning out.

 

[spyug]

Interesting information, especially about the air screw on the carb. Exact same thing happened to me when I tried to clean my carbs after first getting the 750. Luckily our good buddy King of Venus had a spare supper clean and ready to go set for me.

Glad to hear the bike is running much better and as you are now moving into the realm of "mechanically inclined" you should try another couple of simple but very effective mods. May I recommend ( if you haven't already) a) the negative lead from the R/R to the battery terminal (cures a lot of dodgy charging issues) b)the coil relay mod( for even better starting and running, really improves coil performance) Have a look at Mr BassCliff's amazing emporium of GS tutorials for more info.

I did the negative lead mod early on once I saw the charging was sluggish. Fixed things easily.

The coil relay mod I just completed on the weekend and while I haven't ridden yet, the starting is amazing. Routinely, even in warm weather I would need to go full choke and crank for 20 to 30 seconds to get some fire in the hole. With the mod, minus 7 celsius, only half choke and a battery that hasn't had a charge in about a month, she fired on one stab of the button. Blew me away Could put off the choke in about 30 seconds and she idled strongly. Great mod and not as hard as it appears.

The thing with wrenching is it gets easier as time goes on and the more little things you do. In addition, you can't beat the great satisfaction and confidence that comes from fixing something yourself.

Keep at it man:dancing:

Cheers,
Spyug

 

[Nessism]

Good job on going though the carbs properly and doing the job right. It amazes me how many people around here go though monkey motion with seafoam and what have you, when at the end of the day their carbs are hanging on a thread with 30 year old O-rings that are hard and brittle.

Next step, get that sync done. With all this economic turmoil going on world wide, you can get a set of carb tune gauges from Morgan for less than $90. Great deal on a tool that should last a lifetime.

 

[Steve]

As well as you think it's running now, wait until you adjust the valves.
That will take care of your cold starting issues, then you can sync your carbs properly.

When the valves and carbs are adjusted properly and the ignition is working as it should,
you don't have to do much more than think about hitting the START button to get it going. :dancing:

.

 

[Dave8338]

What Steve said. Set then sync...:-\\\

 

[jimfj]

Does that year of GS have CV or Vm carbs?

I just shimmed the needles on my 850 and ...WOW

I really kile the effect and it cured my pesky popping on decel. I didn't shim to the extent that some other people have because its still pretty cold here in Kansas City and I didn't want to go too rich and have to change it in the summer.

The process was extremely simple and cost me virtually nothing. Best part of all is that on an 850 there is no need to remove the carbs from the bike!!!! Took me about 45 minutes from start to finish.

Keep going and good luck,

I too have just clicked over 4000 miles with the bike under me. I purchased mine 9 months ago. I really like the 850, although if an 1100G in black and gold came along I might have to look seriously at it.

Jim

 

[Steve]

I've owned my 1980 GS1100 for almost exactly two years now...

Does that year of GS have CV or Vm carbs?

If it's an '80, it would have CV (BS series) carbs.

.

 

[Dink]

Popping on deceleration is also often related to exhaust sealing issues; another area to look at anyway.

Dink