Announcement

Collapse
No announcement yet.

Mis fire affecting the tacho

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

    Mis fire affecting the tacho

    Hi All, I have been having trouble with this bike for a while now, it hesitates during acceleration, so I was thinking it was a fuel problem but the last time I was out on this bike, during the hesitation the tacho was affected (fluctuating), so for me this is electrical, either the spark unit on the righthand side of seat sub frame or the pick up sensors in the clutch casing. Has anybody else had this problem and if so which item was the cause. Thanks Ian

    #2
    Fluctuating by how.much?
    ​​​​​
    Don't spend money and buy, spend time and learn.

    Comment


      #3
      Are the dash lights changing? I had similar and it was the main ground on the rear of the engine come loose.
      Easy on the throttle, steady on the gears, roll her over gently and she'll last for many years.
      __________________________________________________ ____________
      1988 Grey, Supertrapp stubby, Fox TC, Stage 3 & pods, Vortex clipons, mikuni pump on WW`s batarang, BTT`s res delete, Gino's roller, Brent's sliders and torsion arm, SS thru the SSSA, NC30 rear wheel, & lightened rotor....
      2004 WR450 plated, Trick Dual Sport kit, FMF Power-Bomb Exhaust

      Comment


        #4
        ^^ yes, clean the contact points on the green wire bolted next to the rear brake reservoir.
        "It's only getting worse."


        MY rides: '97 VFR750, '90 Red Hawk, '88 Blue/Black Hawk, '86 RWB VFR700 (3), '86 Yamaha Radian, '90 VTR250, '89 VTR250 (2), '73 CB125, '66 Yamaha YL-1

        Sold: '86 FJ1200, '92 ZX-7, '90 Radian, '73 CB750, '89 all-white Hawk, '88 blue Hawk, '86 FZ600, '86 Yam Fazer 700 , '89 VTR250, '87 VFR700F2, '86 VFR700F.

        Comment


          #5
          Hi All, I have just been out on this bike and it ran the best it has for a long time, I have altered the carbs since the last run, the speedo /tacho is after market, in low gears accelerating hard when it gets to around 7000rpm the tacho jumps to around 9000 (there does not seem to by a miss fire today), it is hard to be sure what is happening because I have to keep an eye on the road, I will change spark unit/ECU and check the grounds mentioned above, the dash lights are sound. I am away over the weekend and thanks for your replies. Ian

          Comment


            #6
            If it is an aftermarket tachometer then what you are probably suffering from is RF interference making the tach jump around. There is a resisiter that can be added to help but I can not recall what range it is but it also may depend on the tach. If it's the trailtech vapor it is documented in past posts from what I recall so you can use the search bar at the top right of the page but someone may chime in as well. If so then usually people get the SV650 version from Trailtech and it has it already inline from what I recall.
            88 Blue Hawk GT - Under construction but rideable (guest approved)
            89 BlackHawk 2.0 - On the lift and being assembled
            90 Hawk GT (color as to yet be determined) - Still on the shelf in crates

            Comment


              #7
              Originally Posted by yorkshire View Post
              Hi All, I have just been out on this bike and it ran the best it has for a long time, I have altered the carbs since the last run, the speedo /tacho is after market, in low gears accelerating hard when it gets to around 7000rpm the tacho jumps to around 9000 (there does not seem to by a miss fire today), it is hard to be sure what is happening because I have to keep an eye on the road, I will change spark unit/ECU and check the grounds mentioned above, the dash lights are sound. I am away over the weekend and thanks for your replies. Ian
              Ya, same happed to me last time I tried to use a tach. ParcNHawk knows the resistor Rob is talking about. He may chime in, but that is a very common issue.
              Don't spend money and buy, spend time and learn.

              Comment


                #8
                The Trailtech latest version tach kit for the SV650 uses a 774 Ohm resistor with a 0.25% tolerance.
                Acta non verba


                '88 Blue 99% stock SOLD
                '88 Restomod
                '22 Yamaha Tracer 9 GT

                Comment


                  #9
                  Originally Posted by Ziggy View Post
                  The Trailtech latest version tach kit for the SV650 uses a 774 Ohm resistor with a 0.25% tolerance.
                  Thanks for the feedback Ziggy!
                  88 Blue Hawk GT - Under construction but rideable (guest approved)
                  89 BlackHawk 2.0 - On the lift and being assembled
                  90 Hawk GT (color as to yet be determined) - Still on the shelf in crates

                  Comment


                    #10
                    Hi All, thanks for the replies, I will look into using a resistor, plus I do not believe the clutch is slipping. Ian

                    Comment

                    Working...
                    X