Announcement

Collapse
No announcement yet.

1978 gs750 timing

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

    1978 gs750 timing

    First let me say I'm new to the biking world but I have played with engines before. Now I have a question in regards to the timing on a gs750. I have changed the points and tried to set the timing. I can get the timing set for 1&4 perfectly. It responds exactly as expected however once I set the plate for 1&4 timing I don't have enough adjustment in the half plate holding the points for 2&3 to get a good setting. The timing light shows 1&4 good at idle and at high speed. You can watch the timing advance as you throttle up and the marks line up for both engine speeds. I just can't get that result from the 2&3 points. At low idle the timing mark is way to far advanced and goes furthur upon acceleration. The bike however runs fairly well but I am getting a small amount of backfiring specially when cold. The bike had been sitting for about 8 years before I got it. The original points where very pitted if that is any help.

    #2
    Ask Earlfor. He's the house point specialist. :-D
    1983 GS 1100E w/ 1230 kit, .340 lift Web Cams, Ape heavy duty valve springs, 83 1100 head with 1.5mm oversized SS intake valves, 1150 crank, Vance and Hines 1150 SuperHub, Star Racing high volume oil pump gears, 36mm carebs Dynojet stage 3 jet kit, Posplayr's SSPB, Progressive rear shocks and fork springs, Dyna 2000, Dynatek green coils and Vance & Hines 4-1 exhaust.
    1985 GS1150ES stock with 85 Red E bodywork.

    Comment


      #3
      I have run into the same problem with my 750, and I think what I ended up doing was changing the point gap slightly to change the initial timing. I think I closed the points by about .002 inch. This retards the spark slightly and gives you more movement in the slots on the backing plates. I always like to set my points as wide as possible, because the rubbing block will wear in. There is usually a range of + or - .002 inch for setting points. It takes alot of careful measuring with the feeler gauge to get both sets of points set the same. It is easy to be off by a couple of thousance.

      Greg O.

      Comment


        #4
        Back in the days (long, long time ago) when I had points to worry about, I always preferred to use a dwell meter to set them.

        Anybody know what the dwell should be on a GS with points?


        .
        sigpic
        mine: 2000 Honda GoldWing GL1500SE and 1980 GS850G'K' "Junior"
        hers: 1982 GS850GL - "Angel" and 1969 Suzuki T250 Scrambler
        #1 son: 1986 Yamaha Venture Royale 1300 and 1982 GS650GL "Rat Bagger"
        #2 son: 1980 GS1000G
        Family Portrait
        Siblings and Spouses
        Mom's first ride
        Want a copy of my valve adjust spreadsheet for your 2-valve per cylinder engine? Send me an e-mail request (not a PM)
        (Click on my username in the upper-left corner for e-mail info.)

        Comment


          #5
          According to my shiney new Clymer man...pre tscc engines is 17 degrees, BTDC at 1500 rpm, 37 deg BTDC above 2500

          Comment


            #6
            Originally posted by lonzo View Post
            First let me say I'm new to the biking world but I have played with engines before. Now I have a question in regards to the timing on a gs750. I have changed the points and tried to set the timing. I can get the timing set for 1&4 perfectly. It responds exactly as expected however once I set the plate for 1&4 timing I don't have enough adjustment in the half plate holding the points for 2&3 to get a good setting. The timing light shows 1&4 good at idle and at high speed. You can watch the timing advance as you throttle up and the marks line up for both engine speeds. I just can't get that result from the 2&3 points. At low idle the timing mark is way to far advanced and goes furthur upon acceleration. The bike however runs fairly well but I am getting a small amount of backfiring specially when cold. The bike had been sitting for about 8 years before I got it. The original points where very pitted if that is any help.

            When the timing is set for cylinders 1-4 what position are the 3 screws in on the large circular plate in relation to the slots. If they are at either extreme it could be that you are using inferior points. i.e. the heel of the points is opening the points too early or too late. Another remedy for the problem is to take the smaller plate with the points for cylinders 2-3 and elongate the slots with a small round file to give extra travel to obtain the required correct timing.

            Cheers

            Don

            Comment


              #7
              I'll have to pull the cover tommorrow and check the slots Thanks

              Comment


                #8
                Hey howdy hey!

                Mr. lonzo,

                I just wanted to say, let it be known that on this day you are hereby cordially and formally welcomed to the GSR Forum as a Junior Member in good standing with all the rights and privileges thereof. Please note that your standing can be improved with pictures! (Not you, your bike!) :-D

                Thanks for joining us. Let us know how you fare.

                Thank you for your indulgence,

                BassCliff,
                (The unofficial GSR greeter)

                Comment


                  #9
                  man cliff, yer slackin...hehehe:-D

                  Comment


                    #10
                    Don't quit your day job!

                    Originally posted by TheCafeKid View Post
                    man cliff, yer slackin...hehehe:-D
                    Yeah, 7 posts into the thread and I finally get around to saying "Hi". I need to quit my day job so that I can welcome all of the new people. There's a rumor going around that my greeter's salary would double if I went full-time. I'll have to check on the benefits package first and let you know. I'll have my people call your people.

                    Thank you for your indulgence,

                    BassCliff

                    Comment


                      #11
                      heheh we'll do lunch...

                      Comment


                        #12
                        Thanks for welcome. I've been reading this site for a while and I can't believe what an incredible source it is. Look forward to all the answers to my questions. PS I'll post picture of the bike as soon as I figure out how and have the time.

                        Comment


                          #13
                          Originally posted by BassCliff View Post
                          Yeah, 7 posts into the thread and I finally get around to saying "Hi". I need to quit my day job so that I can welcome all of the new people. There's a rumor going around that my greeter's salary would double if I went full-time. I'll have to check on the benefits package first and let you know. I'll have my people call your people.

                          Thank you for your indulgence,

                          BassCliff
                          Hey Cliff how come you never welcomed me when I joined in July. Could it be that you weren't the UNOFFICIAL WELCOMER back then. haha

                          Cheers Don

                          Comment


                            #14
                            When you are starting the proceedure and starting by setting the 1,4 points on the breaker plate, the first thing you do is center the 12 oclock screw on the breaker plate in its adjustment slot and lock it down. Gap the 1,4 pointset to 14 thou with the crank set to |F1. That centers the preliminary setting to middle of the adjustment range. You should then have enough adjustment clockwise and counteclockwise to fine tune both the 1,4 and 2,3 sets. (unlock and rotate the breaker plate to fine tune the 1,4 pointset........and then lock it back down) If you still are running out of adjustment on the 2,3 set, you can redo the whole setup starting by setting the 1,4 points to break with the 12 oclock breaker screw set off center to begin with. If you have been runing out of adjustment clockwise on the breaker plate for the 2,3 pointset, start over with the 1,2 set and instead of centering the 12 oclock breaker plate screw in the adjustment slot, move the starting point counterclockwise and that will give you all, or the majority of your adjustment range on the main breaker plate and half plate in a clockwise direction.

                            Earl


                            Originally posted by lonzo View Post
                            First let me say I'm new to the biking world but I have played with engines before. Now I have a question in regards to the timing on a gs750. I have changed the points and tried to set the timing. I can get the timing set for 1&4 perfectly. It responds exactly as expected however once I set the plate for 1&4 timing I don't have enough adjustment in the half plate holding the points for 2&3 to get a good setting. The timing light shows 1&4 good at idle and at high speed. You can watch the timing advance as you throttle up and the marks line up for both engine speeds. I just can't get that result from the 2&3 points. At low idle the timing mark is way to far advanced and goes furthur upon acceleration. The bike however runs fairly well but I am getting a small amount of backfiring specially when cold. The bike had been sitting for about 8 years before I got it. The original points where very pitted if that is any help.
                            Last edited by earlfor; 11-01-2007, 09:25 PM.
                            Komorebi-The light filtering through the trees.

                            I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

                            Comment


                              #15
                              The weather's here, wish you were fine!

                              Sorry I missed you.


                              Originally posted by Suzuki_Don View Post
                              Hey Cliff how come you never welcomed me when I joined in July. Could it be that you weren't the UNOFFICIAL WELCOMER back then. haha

                              Cheers Don
                              Mr. Suzuki_Don,

                              I think you're right. That may have been before I was nominated to be the "official" unofficial part-time greeter for the forum. Soooo.... I guess you're out of luck. 8-[ :-D

                              But enough of this thread-jacking. Move along....There's nothing to see here...Move along....Let's keep it moving.....

                              Thank you for your indulgence,

                              BassCliff

                              Comment

                              Working...
                              X