GS500E ignition problems

[Michael Wiesenberg]

Help! My GS500E has problems that my local dealer cannot remedy.

Symptoms: Usually going at freeway speeds, suddenly the bike slows
way down and the engine does not want to keep going. I have to get
out of the fast lane and move over to the right when this happens, and
at this point I have difficulty keeping the engine going. I suspect
it is firing only on one cylinder. This is intermittent, and it
sometimes fixes itself. When I took the bike to my favorite mechanic
at a Honda dealer, he was able to reproduce the problem, but not solve
it. He suspected the igniter, but didn't have one to swap in to test
that theory, and did not want to charge me the $300+ for a new one,
which might not even be the problem. He sent me to a Suzuki dealer in
the hopes that the dealer would be able to try the igniter theory, but
apparently no bike with a similar igniter came in during that time.
The problem happens regularly to me, yet the dealer had the bike for a
month, and it happened not once. Mind you, the shop manager told me
the mechanic took it on the road only for a total of about 35 miles.
I have had an EBay watch out for igniters, but nothing that would fit
my bike has been posted. I suppose the problem could also be coils,
but I would think that would have been a simple thing to check. (You
can see, I'm no expert.)

Anyway, my questions are: Is anyone familiar with this problem, and
able to offer suggestions? Does anyone know where I could get an
inexpensive igniter to try swapping into my bike? Would anyone be
willing to let me try theirs for a week or so? Any other thoughts?

I have contacted Fremont Cycle Salvage, and they can sell me a CDI box
that would fit (from a 98) for $125. The guy I spoke to suggested
that he would hate for me to unnecessarily spend $125, though, since
when a CDI box goes, it usually goes completely, not showing the
intermittent problems I have been having. He suggested first I try
replacing the post generators, which they will sell for $50. Does
this solution sound right? I would greatly appreciate a direct reply;
I have been having news server problems and cannot always monitor the
news groups.

Thanks.

q

[Emmett Lyman]

Mike,

You might want to post this on the message board at www.gstwin.com, a site
dedicated to the GS500.

Good luck,
Emmett
'93 GS500E

Michael Wiesenberg <queu...@pacbell.net> wrote in message
news:de2d1c35.0108...@posting.google.com...

[Carl Westman]

I spotted something similar to your problem mentioned at this site:

http://www.eurospares.com/gsfaq.htm

Quoting it:

FUEL AND EXHAUST SYSTEMS
...
One reoccurring item of annoyance on the GS500 is the fuel petcock. Many
emails talk about a fuel starvation problem which was remedied by placing
the fuel petcock in the reserve or prime position. Some folks have replaced
the stock petcock with a dry brake quick disconnect. However both of these
remedies leave you without a reserve.

Hope that helps,

Carl

[Kaybearjr]

>From: queu...@pacbell.net (Michael Wiesenberg)

>Symptoms: Usually going at freeway speeds, suddenly the bike slows way down
and the engine does not want to keep going.

Once upon a time, ignition systems were so unreliable, that anytime the engine
gave problems, mechanics would start replacing points and condensors and
coils...

But nowadays, ignition modules fail completely, with no warning, and NEVER
exhibit intermittent problems...the signal generator on the end of the
crankshaft also works all the time, or it doesn't, which leaves the wiring
harness or the carburetors as the culprit...

Check all the connectors. Look for loose connectors or melted
connectors...anytime a connector turns dark colored, it has probably overheated
from being too loose...

I had the ignition switch on one Suzuki overheat and melt the contacts inside
the switch...

I had the power connector fall off of one coil, and had to ride my
four-cylinder bike home on two cylinders once...

But it sounds more like a fuel starvation problem than an ignition problem...I
once had a pinched fuel hose that was driving me nuts trying to find the
problem...

Maybe some fuel system cleaner in the gas tank will
clean the crud out of the fuel lines and fuel shutoff needle valves...it only
takes a couple of ounces in a tank of gas...

Open the float bowl drain screws while holding a rag under the carburetors to
check for rust and water in the float bowls, and if the bike has a filter on
the petcock, clean it out...

If any rust or water comes out of the float bowls, you will probably need to
pull the carbs off and clean the
jets thoroughly...

Check the vent on the gas cap...next time the bike craps out on the freeway,
open the gas cap and see if the symptoms go away...

If the bike has a vacuum-operated petcock, make sure the vacuum hose has no
splits or cracks and is attached firmly to the petcock...

And, don't overlook the possibility of loose carburetor
mounting clamps allowing a vacuum leak...I had that
problem once, and it was very frustrating to get stuck at the bottom of a long
hill that the vehicle couldn't climb without seeming to run out of gas...

[Emmett Lyman]

Actually, that FAQ isn't completely accurate, at least in my experience.
Using the Prime position on my bike takes fuel from the "On" rather than
"Reserve" source. As long as you can get some fuel flow through the valve,
you'll still have a reserve. Just don't count on a smooth ride when that
happens, as the starvation problem is quite noticeable.

-Emmett
'93 GS500E

Carl Westman <c...@actuaryoncall.com> wrote in message
news:AJEc7.1370$q46.1...@newsread2.prod.itd.earthlink.net...

[Gino]

sound like it is definately a fuel problem, (you may want to stop going to
that dealer!)

Michael Wiesenberg <queu...@pacbell.net> wrote in message
news:de2d1c35.0108...@posting.google.com...

[Thijs Verhoef]

Yep! I had the exact same problems as described above, with my '86 VFR700F
and it turned out that the signal generator connector block was somewhat
loose. Sometimes it made good contact and I had no problems at all and
sometimes the engine just stopped running while I was driving or waiting for
traffic lights. The solution was as simple as clicking the connectors
together, but it was a hell of a job locating the problem. So indeed, check
ALL your connectors. This definately sounds like an ignition problem to me.

success!

Thijs

[jt...@punk.net]

In rec.motorcycles Carl Westman <c...@actuaryoncall.com> wrote:
: I spotted something similar to your problem mentioned at this site:

: http://www.eurospares.com/gsfaq.htm

: Quoting it:

Yup. The petcock on that bike sucks ass. No two ways about it.
Mine got stuck on reserve a couple years ago and I had it replaced
warranty. Could have been worse. The replacement got stuck in
the "on" position. Good thing I was near a gas station. I'm on
my third Suzuki petcock now. All replaced at no cost to me but
I'll probably come up with a better solution next time. (The
extended warranty's up in a couple of months.)

Jamie