GS1000G-carb problems still

[qwagmyre]

1980 GS1000G

The bike had sat for around 15 to 20 years before I bought her. I rebuilt and jetted the carbs to start.
After the rebuild it did not run right and I was not too upset.
Now 5 years, three shops & a lot of money later it runs only slightly better.
I have replaced the tires, brakes, clutch assembly, exhaust, and even bought the cute K&N air cleaners.
The bike now runs pretty good up to 60mph and then fumbles around, I'm assuming it is either a carb not insync with the others or maybe my coils(one of the few things I have not replaced).
A few years back when I found this incredible site, someone had mentioned a company that did nothing but work on carbs. Does anybody know the name of this place?
It only has 3000 miles on it! Please help me!
[-o<
P.S. I live just south of Chicago, if anybody knows of a really good shop.

 

[nert]

seems to be you need to convey 5 years of repairs.
Did it start out stock? new exhaust as in OE, 4 into 1, J.C. Whitney ? etc.
Ignition??points, electronic, Dyna? Centrigugal advance frozen?
Fuel tank?? rusty, fuel flow? Choke help or hurt performance?
Backfire? Bog? Vomit?
"fumbles" around??? need more description.
PRetty good to 60? Full RPM in all gears? Neck snap?

needs lots more info.

 

[qwagmyre]

ok heres more

ok heres more

I bought the bike in 2000. It was stock with original 4 into 2 pipes, still had fairing with working 8track. Original owner bought the bike new then passed away in 82 or 83. It sat in his sons garage until he sold it to dealer, then I bought it for $1750. It had around 1700 miles on it, it has 3000 now.

It ran but barely, I bought rebuild kits from Suzuki and jet kit from Dynajet. It ran a little better then but you could tell the carbs were bouncing all over the place. I then replaced the rock hard tires, repaired a sticking front brake, bought a 4into1 header and had it powder coated. Then I bought the $175 K&N aircleaners.

During one winter I left the petcock open and flooded the engine with gas. So I replaced the clutches upon recommendation from the Suzuki shop.

All of this went smooth enough. When I went to get the carbs repaired, every shop found a new problem, bad o-rings, bad springs, there is nothing left to replace in the carb except the housing.

It was recommended to me that my coils and/or cables could be bad as well. Someone recommended sending my carbs to a company that does nothing but carb work, but I can not remmember the name or find the old message in the forums.

By this time I had hoped to have the bike done and painted.

Oh yeah, as you had mentioned, the bike really takes off until 60-65 mph, I have never had this much get up and go from it before. but I should be able to get past 70mph.

With gas prices this high and the distance I drive to work, this is fun way to save money. Plus you can imagine what my wife thinks about the bike!

 

[omaharj]

Hang in there. There are some really logical methods to determining the problem. My brotrer has a similar problem with his 75 CB360J. Fortunately for you,you're near Chicago,where there's a number of GS "experts". (I think they're favorite beverage is beer.:wink: )

 

[mortation]

Are you saying someone else rebuilt your carbs? Perhaps you should tear them down yourself and do it following the guide on the front of this site. Then bench sync them, install, and use a manometer to balance them. Or grab a used set off eBay and start from scratch to make sure you have all OEM parts and no one else's mistakes

Since it only has 3000 miles I wouldnt think you would have an issue with your valves, but what about your timing and chain? Have those been checked? Did the 80's model still have points like the 79's?

 

[nert]

Since your carbs and exhaust is no longer OE, i am of liitle practical use, only theory. The best bet is to find another 80' 1000 owner with the same 4 into 1 exhaust the same air filters, etc. I am sure that guy/gal has all the jetting properly worked out. By changing the air filter and/or exhaust, you change the air flow dynamics through the carburetor and therefore change the intended fuel/air delivery. As "mortation" suggested, disassemble the carburetors per the guide that is available at this site. Carefully clean all jets and passeage ways (record all jet numbers while your in there) and adjust the float levels. Bench syncronize to start, then sync dynamicly. YOu need to start with proper fitment of the main fuel jet. (wide open throttle). This may all seem overwhelming to you now, but that is part of the price that needs to be paid for modifications from stock. EVERYTHING now is a variable that can affect performance. There is TONS of documentation on this site for properly dialing in the correct jet sizes and needle positions. Again,,,describe the performance more accuratley. Does it seem to fire on all 4 cylinders? misfire? chug? backfire? (if you are not expiereincing cylinder misfire and backfire through the exhaust, your ignition is probably ok) Does applying the choke help or hinder? does it seem to accelerate better just for an instant once you begin to back off the throttle? That bike, should rip the corners of your mouth into a big wide grin after cresting 5,000 rpm. REPOST, and BEG for someone to reply with proper jetting for a 80' GS1000, 4 into 1 and K+N pods.

 

[tkent02]

Let someone familiar with the GS1000G it go for a ride....

Let someone familiar with the GS1000G it go for a ride....

He can probably tell you in one minute what is wrong with it.
There are GSers everywhere, you can find one.
But if it will only go 60 it's probably not getting enough gas to the carbs.
Inline filter or petcock screen clogged?
Gas cap vent clogged?
Something along those lines.

 

[twr1776]

I would also suggest doing the stator papers and going thorough the ignition system to rule out any issures with spark. Do you still have the original petcock and carb intake boots? A lot of problems start with those and you might want to replace them if they are OEM. I did not have those issues but replaced them anyway on the 20+ year old theory. If you have any fuel delivery or igniton issues you will never be able to get the carbs right. Start with one system and rule it out or repair and go from there. The carbs should be the last thing you do after ruling out the ignition and fuel systems first.

 

[omaharj]

He can probably tell you in one minute what is wrong with it.
There are GSers everywhere, you can find one.
But if it will only go 60 it's probably not getting enough gas to the carbs.
Inline filter or petcock screen clogged?
Gas cap vent clogged?
Something along those lines.

That's what I'm thinking. Is it a rustfree fuel delivery system? Jets may be clogged with itsy-bitsy,teeny-tiny,you-need-a-magnifying-glass-to-see.pieces of rust. Or your fuel isn't getting to the carbs. A fairly easy way to eliminate gas/fuel kine as a problem is to jerry rig a temporary gas supply and line to carbs. Pobably cost ya 2-3 dollars to make and in less than an hour you can have more info.

A clue is you say you left your "cockpit open". I assume you meant petcock on prime. I don't think it should have leaked unless thre floats were sticking. That tells me your carbs ain't right.


Good Luck!

 

[feelergaugephil]

save a lot of hassle, I rebuilt my GS1000G carbs which had crap in them, several tear downs and cleaning them, I threw them about 18ft into a brick wall!!!!!
I bought a clean set from ebay for $120 and never looked back.
I have the K&N air filter on mine too.

 

[Guest]

The guy you are asking about is wiredgeorge. Do an advanced user search and contact him if you want. I personally would do it myself. If you have a dynojet installed do you still have the leftover jets? What are your spark plugs telling you. Do a search for "plug chops"