Technical advice please

[zblip2]

Hi

It's been a while since I posted (too much work and in Canada there is such a thing as whinter...) but it's that time of the year and I want to fix up my gs850G for the comming season. I'v got two issues with my bike:

1) Strange electrical bug with the starter

Last year my starter went dead. I sent the bike to the shop and they told me the wires had been tampered with (wich was true) thrue the years an they fixed things up. After a month of smooth sailing, I start my bike one morning and the starter wouldn't turn. Instead, there was smoke coming out of the side pannel (where the wires are). There is a wire in there that over heated and melted off its plastic cover. It happened all at once. I sort of wiggled the wire to see if it was touching something and the bike started. A week later, the same thing happened but tis time the wire just melted away all together (the metal portion). The wire is no longer conecting what it was it was conecting. Funny thing, the bike works just fine now (electricly speaking). Any idea what happened here?

2) Knocking (ticking) engine noise when twisting throttle to accelerate.

This only happens when the motor is realy hot. This usually happens when driving in city traffic during the summer. Going of at the light or pushing to accelerate in traffic. It shows up at low to medium rpm. Also, I sense a dip in power at the moment the ticking sound appears.

Any idea what this is about?

Thanks

[80-81, GS 1100]

I would suggest you get a Manuel and look up in the
wiring diagram that area of the bike you had the problems with.
Check the connections and make sure its stock.
Also check all the other maintenance items like valve
clearances. I am not a mechanic but thats what
I would do. After you check those items see if
the bike is charging at proper voltage. It sounds
to me that a previous owner changed some wiring
and your bike may be an electrical fire waiting to happen.

[posplayr]

As GS1100 mentioned

You could have several things wrong just given the age of your bike and the apparent lack of attendion due to PO incompetence. Someone technically competent should go through your electrical charging system. It is not that hard but you do need to know your way around a VOM (volt Ohm Meter).

The general problems with the GS's are that the bullet connections around the charging system (primarily concentrated under the side cover) become degraded over time and cause a situation where the regulators (in the R/R) have bad connections and the closed loop regulations goes haywire. Haywire means amoung otherthings with over charging and frying stators and or R/R or other stuff. It needs to be fixed as the OEM electrical system is not very tolerant of these bad connections.

I would follow the stator papers as suggested but first you need to do the obvious stuff.

1.) Check for any non OEM wiring changes. This will be indicated by "new" electrical tape, different colored wire or non OEM lugs and/or connections. Other than grounding modifications to the schematic to be mentioned in item #3 below make sure that the original schematic is intact.

2.) Replace all bullet connections with blade type connections on the three stator legs, as well as the plus side of the R/R output. The negative side will be treated in #3 below.

3.) This is the first actual schematic modification I would suggest. It is basically the same as has been described on this fourm as connecting the R/R negative directly to ground, but I have "improved" on this somewhat I hope. The modifications worked and checked out on my 1981 GS750EX and should work on your bike as well.

On the last post on this leg is a description and it points to another fourm page for the pictures. of the mods. The whole thrust of this final important element is to establish a single point ground at the R/R case on the side plate. The side plate is mounted in rubber and can have troublesome grounds. The R/R case single point ground is then grounded directly to the negative side of the battery. The single point R/R case ground picks up the R/R and the solenoid.

The last solenoid ground may be one of the parts to the pussle for your starter problems. At least on my GS750, there was a ground strap completely fried that went between the battery box frame ground and the side plate at the seloniod. The strap daisy chains from the harness but on mine the harness only suffured minor melting while the primary ground smoked off all of the insulation. This basically means there is a lot of current trying to find it's way back to ground and this little ground reference wire could not carry the load.

http://www.thegsresources.com/_forum/showthread.php?t=120504

Finally .4) With the above required changes, and assuming your stator and R/R are still functioning you should get through the stator parpers tests with flying colors (but not flying sparks).

Remember the voltage differences between the battery terminals and the R/R respective terminals (i.e. + to + and - to -) should not exceed about 0.2 volts at 4000 RPM. It is pretty easy to have 0.2 volts diff at idle and then well exceed 0.5 volts at 4000 rpm. This is what you want to fix.

Hopefully I have not added to the confusion.

Posplayr

[litshoot]

for the wires definately go through them a run of wire should have .2ohms resistance, i had high resitance on my car and it melted wires when starting. the resistance makes it get hot. i'm not positive but it should be no more than 1 ohm for a length of wire from any load to the power or ground.
the ticking sound like the engine gets hot and is pinging. can be your timing is a little over advance, but not badly check all the usually problem areas (vacuum leaks, valve clearance, etc.) then go through your timing and check it again. to make sure its right.

none of this is hard or expensive. just get a decent dvom(i recommend digital vom just for ease and its use if you get anything that has a computer on anything you may ever use it it doesn't cause damage. a timing light, manual and a lot of time. good luck.

[posplayr]

litshoot

I dont think I would really trust an ohm reading to tell if your charging is really up to snuf. I haved used the ohm meter to measure teh resistance of some connectors hen I first started testing, but as you know you should make sure the battery is disconnected.
The full load tests (at 4000+ RPM) should be based on voltage are really "the end all be all". I personally go from the the battery center terminal (not the connector) to the R/R reference points using voltage measurements. This precludes any funny things that might happen as the current increases above what the VOM would put out to measure current as well as measuring the actual battery connection voltage drop.
You want something less than 0.1-0.2 volts and it is not clear what the current draw actually is(it also changes with load) it is again difficult to relate ohms to voltage because of the unknow current (unless you use a current clamp).

The main issues are overvoltage on the battery and false reference voltages for the R/R. Theoretically you could do this by measuring Ohms , but there could be some gotchas. I would just stick with volts and keep the battery connected.

As for a car, and trying to determine cable resistance for an engine starter, measuring voltage drop is the easiest and safest (at load).

Good Luck

Posplayr

[BassCliff]

A little TLC. OK, maybe a lot.

Mr. zblip2,

I know it's a hassle, but the old wiring on these bikes needs all the help it can get. The best way to help it is to make sure all of the connections are clean. Start in the headlight bucket and check every connection on the wiring harness all the way back to the tail light. Look under the tank and seat too. Take apart all the bullet connectors and clean them. You may wish to reassemble them using dielectric grease to guard against moisture. If any are bad, replace them with spade connectors. Check the fuse box for clean connections and replace all the fuses with good fresh ones.

Then go to my little BikeCliff website and download the factory GS850G Suzuki Shop Manual. Have you read The Stator Papers to really get familiar with the charging system on your bike? Definitely replace the bullet connectors between the stator and the regulator/rectifier with spade connectors and run a dedicated ground from the r/r to the negative terminal of your battery. When was the last time you adjusted the valve clearances? See the manual and the pictorial guide on my little website for instructions. If your engine runs too hot all the time, that could indicate a lean condition in the fuel mixture. If you need to clean/rebuild your carbs this is the guide. Otherwise get your carbs tuned and balanced so that you don't damage your engine from running lean and hot. Change all the fluids regularly. Pictorial guides for this are on my little website too.

Where is the "ticking" coming from? The top of the motor could be valves. Lower could be the cam chain tensioner. Lower than that could be crankshaft or bevel gears. Let's hope it's not there.

Let's keep your classic bike running well. Keep us informed.

Thank you for your indulgence,

BassCliff

[SqDancerLynn1]

I would bet the starter is getting tired/ worn out brushes

[zblip2]

WOW!
That's a lot of quality replies. Thanks everybody. I will certainly check out all of these points. I think the theory about the faulty ground (which in the absence of, forces the high voltage currant to find it's way through the smaller wires) is a good one. I'll keep you guys posted on developments.

Thanks again