A gs650glz with POOR, TERRIBLE starting accelleration!

[Anonymous]

I recently got a 1982 gs650glz recently taken out of winter storage, but I am having a few problems with it.

1) The battery was dead when I got it, but it will run fine once it's jump started via a car battery. This has an easy fix: A new battery! I'm telling you this because it may have a relationship to the actual problem:

2) This problem is a little bit wierder: The bike will not go off the line how it should. No matter how much gas is given, the bike drops down to about 800 RPM, loses all of it's power, and takes off incredibly slowly... My 50cc Honda Spree has more power than this bike at a stop sign! It will stop fine, but once you need to get going again, it's really hard... It is impossible to get it going at all when stopped and heading uphill. It will just die no matter how much gas is given.

I hope somebody in here has had a similar problem and knows exactly what is wrong. The sparkplugs haven't been checked quite yet, and the carb is yet to be cleaned, but the previous owner claimed that the bike always performed this way and just assumed for it to be normal (I know it isn't normal).

I'm aware that most replies will be to check the spark plugs and overhaul the carb, but I was just curious if anybody knew of a different problem that could be causing the lack of starting power... Or if anybody knew that it was specifically the spark plugs or carb. I'm just worried because the previous owner lived with it like this...

The gas has been changed to new gas and all exhaust pipes feel hot to the touch after use. Would the fact that there is a dead battery have any affect on this? Would a carb cause this much of a problem? Oh, I forgot to mention that the bike seems *better* at mid to high range RPMs, but it is still lacking in accelleration power.

Anyway, thanks for any help you give,
b

[Anonymous]

I forgot to add some key information: In the higher gears, it bogs down badly when going up hills.

[Anonymous]

It's unlikely that anyone can tell you exactly what the prolem is, unless they're psychic. That's why most problems must involve trouble shooting. First, get a new battery. You're going to need one anyway, regardless of whether it is contributing to the poor performance. Then it's a matter of finding out whether the problem is 1- mechanical (doubtful, but a compression check couldn't hurt), 2-electrical..check plugs for condition and good spark. If not, coils and wires are suspect. And finally (and most likely) 3- fuel and intake system. Jets and carb orifices must be clean. No air leaks at carb manifold. But first, I would put in new battery and change the plugs.

[earlfor]

The first thing to do is put a new battery in it. Next, I would check and clean all the electrical connections including grounds. Since it starts and runs, for now, I would assume the ignition system is working although checking the timing would be a good idea.
After that, the carbs are suspect, but before I would do any carb adjustments, I would remove and seal the induction boots between the carbs and cylinder head and also check them for cracks. If those boots are leaking, no amount of carb cleaning or adjustment will be to any avail.

Earl

[Anonymous]

Hows about cleaning the carbs?

Sounds like dirty carbs to me. Maybe they need to be synchronized, but I bet they are cruddy.

[Dink]

I sugest that this may have a lot to do with the idle circuit , either being blocked or mal-adjusted,as this would explain the lack of power just off idle and would also contribute to a general lack of power higher in the rev range ,understandable when you consider the idle circuit is always supplying fuel right through the rev range and a lack would make it lean every where.
Dink

[Anonymous]

Your main complaint seems to be at acceleration! Right? All of the previously suggested solutions are certainly valid. But at best we can only guess because what you describe could be a symptom of one or more problems. But you knew that, right? The one thing, I notice hasn't been mentioned yet is: Your carbs are CV type (constant vacuum). I don't know if you are familiar with how they work so........... The throttle activates a butterfly valve on each carb. The opening of the butterfly allows engine vacuum to activate a diaphram which pulls up on the throttle slide and opens up the carburator throat so that increased fuel air mixture can go into the engine (low and behold, this is what should be happening on acceleration). This event is dependant on engine vacuum (no induction leaks and intact diaphram) and freedom of the slide to move when vacuum is put on the diaphram. This is just one more thing to consider.

So after you have replaced the battery, done a compresion test, replaced plugs, done an ignition and electrical check, cleaned the gunk out of the fuel bowls and adjusted the floats, and checked for induction leaks, think about how the carbs work and make sure they are doing what they are supposed to do.

You know that the guy you bought the bike from doesn't know what he is talking about (the bike should give you a thrill) and that whatever he tried to do to remedy the problem didn't work, so the problem is probably not one that is resolved by just giving it a tune up.



Good luck and by all means have fun.

Blaine

[Don Lobacz]

Make sure that there is a good air filter in the stock airbox and that the cover is properly sealed tight.

[nabrams]

I fully agree with Earl and Don. I had an almost identical problem.
You're almost certainly going to have to do a thorough carb cleaning (use a good manual - like Clymer).
Check your air filter element and check for any air leaks at any of the boots connecting the carbs to the engine and air box. Also, seal the tiny air leaks between the air box lid and air box (try silicone). In my case (1980 GS450L), the air filter element had disintegrated and there were tiny air leaks in various other places. I had cleaned the carbs (several times) and it would not run right. It was only after I resolved all the air flow and air leak issues that the bike ran decently. The CV carbs on our bikes are VERY sensitive to improper air flow.
You will drive yourself nuts cleaning the carb a million times (as I did) only to finally realize that the air flow (or leak) problems were critical as well.

[brs127s]

Definitely check the air filter. I had a similar experience with my old 77 550. It would idle okay and take off, but when I gave it gas, it would cut out. Took the aire filter out. Someone has used seat foam, which is much to dense, for the filter. Tried running the bike. It ran up to a high rpm than before, and then cut out. Next I put a piece of actual filter foam in the filter frame and took it for a spin again. No problems at that point. It took off like a rocket and never cut out.