Announcement

Collapse
No announcement yet.

Chasing my electrical problems on my GS450

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Chasing my electrical problems on my GS450

    My volt tester says the Stator/R/R system is at 14 plus volts, even at idle speeds. Using a cheap HF multimeter and hope the numbers are correct. I tightened down the neg terminal on the battery because the gauge light displays are flickering but No improvement. I previously had cleaned up and tightened the ground wire to the engine. This is a new light flickering issue I just noticed recently.

    On one attempted start .... the starter motor and all lights abruptly quit and shut down as though I had a direct battery short! The headlight MAY have burnt out on that attempt .... and now suddenly does not work at all. All seemed fine on the next attempt and engine started and all lights stayed on .... except the headlight. I will try to see if the headlight connections are getting voltage.

    If I need a new headlight, is there a newer brighter design I can buy for my gs450 to improve it without putting too much of a load on the charging system? Thanks for any help on these issues.
    Dennco2
    1985 GS450
    Stock condition and a work in progress

    sigpic

    #2
    You need to go through your wiring harness and clean/check/replace all your connectors. Open up your gauge and check the bulbs - they may be loose or have corrosion. Pull the headlight off and rule out whether or not it works directly from the battery.

    Did you blow your fuse? I'm confused what happened if the lights all went out and then you just tried it again and it worked without replacing the fuse.

    Also put your bike in your signature since you have multiple threads and it will make it easier to read.
    1980/1981 GS450 - GS500 Cylinder + Piston Swap - "De-L'ed", custom seat, CB350 bits, 18" rear, etc.
    1977 GS550
    1977 GS750 - Cross country trip thread

    Comment


      #3
      Originally posted by sam000lee View Post
      You need to go through your wiring harness and clean/check/replace all your connectors. Open up your gauge and check the bulbs - they may be loose or have corrosion. Pull the headlight off and rule out whether or not it works directly from the battery.

      Did you blow your fuse? I'm confused what happened if the lights all went out and then you just tried it again and it worked without replacing the fuse.

      Also put your bike in your signature since you have multiple threads and it will make it easier to read.

      Previously I had pulled ALL the bullet connectors apart to clean and reconnect with dialectric grease ... in the headlight bucket .... around the 2 coils .... inside the R/R area from the stator ..... and over the rear wheel connections to the tail light. I pulled on them slightly to verify the connections were tight. I did not attempt to clean the multi junction connectors. Is that also needed to be done? I couldn't figure how to do those.

      I'll be checking the fuse again later. I had also opened that fuse holder and polished the connection. Is there just the ONE fuse on a 85 gs450 ... on the left side by the ignitor? I'll be checking the headlight too.

      DC
      gs450
      Dennco2
      1985 GS450
      Stock condition and a work in progress

      sigpic

      Comment


        #4
        Thanks Sam for suggestions. I haven't got to all the items but did determine the headlight HI beam works and the LO beam burned out. The stock headlight is dreadfully dim so I bought some Sylvania Silverlight 9003/H4 bulbs ..... but forgot the stock headlight was a sealed beam on the gs450. So I have read up a little on that problem and how a few have successfully removed the stock incandescent bulb and secured the replacement bulb with glue or wires or rubber bands. Looks like the best solution is to buy a replacement reflector too ... but which one for easy fitment??

        My cleaned-up ignition switch seems to act up intermittently. Looks like I need to replace it with a new one or a reliable used one. I didn't ride my bike for 3 weeks and when I last tried to start it ... the switch would not turn on the dash lights when rotated to ON. 4 attempts later ... it finally did. Any recommendations on brand name replacement ignition switches?

        My starter button must have gone bad again because I can't get the starter relay to click and start the motor. I cleaned the button back in June and all has been well since ... until now. And I will open and clean all contacts in the throttle and turn signal housings.
        Dennco2
        1985 GS450
        Stock condition and a work in progress

        sigpic

        Comment


          #5
          For the headlight - it might be easier/cheaper to just replace the assembly. You can find units that fit in the stock bucket.
          Seems like they still sell OEM, too: http://www.partsoutlaw.com/oemparts/...4bd3c/headlamp

          If you remove the ignition switch, the wires on the back are pinned and solder in. If you're set on keeping the keys matching the tank/seat lock it's worth getting it apart to redo. On mind I ended up ditching it after finding some pretty burned out wires. I have a kind of unconventional set up but there are lots of cheap aftermarket ignition switches.

          Here's a good option to keep a single key: https://www.ebay.com/itm/1980-Suzuki...RWuPwV&vxp=mtr

          To test the starter relay, you can short the two main (larger) terminals to see if it cranks the engine (make sure you're in neutral!). If you hear a click but the starter doesn't turn, then that could be your issue. If the relay is working then yeah maybe it's just your switch...if you have a multimeter you can also use that to test for continuity with the button engaged.
          Last edited by sam000lee; 10-18-2017, 11:40 AM.
          1980/1981 GS450 - GS500 Cylinder + Piston Swap - "De-L'ed", custom seat, CB350 bits, 18" rear, etc.
          1977 GS550
          1977 GS750 - Cross country trip thread

          Comment


            #6
            Found headlight solution?

            My internet search for a suitable replacement headlight led me to buying a complete reproduction chromed headlight bucket and lens assembly from 4 into 1 company. $36 plus $11.xx shipping. Comes with H4 bulb. I could use that bulb or install the Silverlights I already bought. I don't see any compatibility issues with this purchase? About the same as buying a used Suzuki assembly with a replaceable bulb .... without the rust issues.

            build-your-own-6.5-.jpg

            I ordered without the wire grid. Mounting width is 6.25" for the support brackets ... which looks close to the stock dimensions. I hope this works well.
            Last edited by dennco2; 10-18-2017, 04:48 PM.
            Dennco2
            1985 GS450
            Stock condition and a work in progress

            sigpic

            Comment


              #7
              Just watch that "chrome" very carefully. Lots of hard wax or something?? My experience with aftermarket headlight bucket was that It will dissolve if I spit on it..

              Comment


                #8
                Only my second post, but I've tinkered with two GS450s now and have found the same problem on both, which will apply to you. One of the wires from the stator routes behind the R/R, but instead of going directly to the R/R, it routed all the way through the headlight bucket for absolutely no reason (well documented on here, but probably a wiring harness common to multiple bikes). Both my two had burned up the multi-wire connector in the headlight bucket.

                Take headlight out of bucket, find one of the big multi-wire connectors that has a red jumper wire (a wire coming out and right back into another slot on the same side of the same connector). My bet is you'll also find that connector is brown and brittle instead of white shiny plastic. That is your culprit. You'll have to re-build that connector to make the other applicable connection, but don't re-build the jumpered wire, just make its connection directly to the R/R where it should have been done.

                Comment


                  #9
                  Originally posted by Gorminrider View Post
                  Just watch that "chrome" very carefully. Lots of hard wax or something?? My experience with aftermarket headlight bucket was that It will dissolve if I spit on it..
                  I will be checking that out when I get it. One reviewer of the product said he was surprised of the quality ... we'll see.
                  Dennco2
                  1985 GS450
                  Stock condition and a work in progress

                  sigpic

                  Comment


                    #10
                    Originally posted by blake989 View Post
                    Only my second post, but I've tinkered with two GS450s now and have found the same problem on both, which will apply to you. One of the wires from the stator routes behind the R/R, but instead of going directly to the R/R, it routed all the way through the headlight bucket for absolutely no reason (well documented on here, but probably a wiring harness common to multiple bikes). Both my two had burned up the multi-wire connector in the headlight bucket.

                    Take headlight out of bucket, find one of the big multi-wire connectors that has a red jumper wire (a wire coming out and right back into another slot on the same side of the same connector). My bet is you'll also find that connector is brown and brittle instead of white shiny plastic. That is your culprit. You'll have to re-build that connector to make the other applicable connection, but don't re-build the jumpered wire, just make its connection directly to the R/R where it should have been done.
                    I remember reading up about that problem as well and will look into it soon. I'll be pulling all the wires out of the headlight bucket anyway ... as I replace the old with the new headlight and bucket combo. What you say might have blown the LO beam ... or it just got old and tired. The HI beam still works fine. It looks like that headlamp has been in there a long time! Thanks for the good suggestion.
                    Dennco2
                    1985 GS450
                    Stock condition and a work in progress

                    sigpic

                    Comment


                      #11
                      just an addendum a consumer tip:
                      I bought a new plain-jane 55/60w H4 halogen bulb yesterday. Reading the back of the packages while choosing, I noticed that the more expensive "brighter" ones had 1/10th of the estimated lifespan the cheaper ones offered....That may be acceptable for the extra brightness but it's still useful to know that replacement is more frequent...

                      This clue may go towards reliability too...as in Motorcycles being a tougher environment for bulbs...

                      Comment


                        #12
                        but instead of going directly to the R/R, it routed all the way through the headlight bucket for absolutely no reason
                        There is one, sort of. The original Rectifier/Regulators only "regulated" ONE leg of the stator. The other two legs were merely rectified.(I get this from the circuit diagram in the manual)

                        So, when your headlight was off, your charging output was running at 2/3, unregulated. When your headlight was on, the output was 3/3 and over-voltage was controlled as that 3rd leg was shunted to ground past set voltage...It's kind of clever, really, but the long circuit to handlebars and the lightswitch there...and other concerns...well..it's certainly not proved out longterm.

                        EditADDED (thanks JP) OOps Wrong-my mistake-
                        The other two legs were merely rectified.(I get this from the circuit diagram in the manual)
                        Last edited by Gorminrider; 10-25-2017, 09:43 AM.

                        Comment


                          #13
                          Originally posted by Gorminrider View Post
                          There is one, sort of. The original Rectifier/Regulators only "regulated" ONE leg of the stator. The other two legs were merely rectified.(I get this from the circuit diagram in the manual)

                          So, when your headlight was off, your charging output was running at 2/3, unregulated. When your headlight was on, the output was 3/3 and over-voltage was controlled as that 3rd leg was shunted to ground past set voltage...It's kind of clever, really, but the long circuit to handlebars and the lightswitch there...and other concerns...well..it's certainly not proved out longterm.
                          Take heed that when your headlight burns out and you have no off switch, you're feeding another 50-60 watts into the regulator to dispose of as heat somewhere - read stator. If your Lo beam burns out use the Hi and turn the bucket down a bit.

                          I'd think that the newer series regulators can handle that much 'underload' but the old ones were on the edge to start with. Without a headlight, there's a lot of watts to dump.
                          '82 GS450T

                          Comment


                            #14
                            ^^yes, good point- it might be one more way to explain why these particular regulators burned out so often ,even though the rectification on two legs may have survived... I've had a couple of these and then too, fairly often people show up here on the forum with "low charging voltage" when they still have the OEM R/R...

                            But the old silicone SCRs...I hae mae doots even when not shunting full...the rapid repetition ...as in as soon as they shunt, voltage drops, so they "close"-voltage rises again, so they open and shunt again etc etc...rapid cycling and each cycle is actually a curve upward-not so instant as an ideal case suggests. It might act like higher resistance and get them just as hot.
                            The Honda ones of the same vintage shunt all three phases and perhaps they survived better merely because the speculated problem above was spread among 3 scrs...

                            Speculating again, but given all the above, It MIGHT have been a "solution" to run HIGH beam ALL the time to preserve the original one-phase regulator...(excepting(sigh) bulb life suffers..)

                            Comment


                              #15
                              Originally posted by Gorminrider View Post
                              There is one, sort of. The original Rectifier/Regulators only "regulated" ONE leg of the stator. The other two legs were merely rectified.(I get this from the circuit diagram in the manual)

                              So, when your headlight was off, your charging output was running at 2/3, unregulated. When your headlight was on, the output was 3/3 and over-voltage was controlled as that 3rd leg was shunted to ground past set voltage...It's kind of clever, really, but the long circuit to handlebars and the lightswitch there...and other concerns...well..it's certainly not proved out longterm.
                              Not so. One leg went directly to the rectifier as did another which also went to the regulator. These two legs were always on, and regulating one leg was sufficient; besides, the legs join at the Y. Charging was never unregulated. The third leg took a tour to the bars and switched in with the headlight to augment the output.

                              Not that any of this matters anymore. We have the SH775...
                              '82 GS450T

                              Comment

                              Working...
                              X