Tachometer and speedometer bounces....

[racerman_27410]

Speedo jumping would be the cable,either not tight at both ends or dirty.
I didnt find anything today.I found out that I had no front turn signals so I fixed them.I had a bad connector (melted)from the generator to the battery that I cut out and fixed.How many volts should I see when im at 1100 rpm ?Volts check the same everywhere at the frame the engine and at the battery.Starts easy idles good but runs rough and almost seems to run on 3 cylinders if I dont hold the shifter up when in 5th or down when in 1st.

how does it run in 2nd.3rd and 4th ?

does the engine rev and run ok in nuetral ?     

[Flying Scotsman]

2nd and 3rd need changed but they are the same as 1st 4th and 5th it is just easier to tell in 5th because you cant shift up any more.
I have a set of gears here I need to put in but I dont have the tools yet.She revs ok in neutral but theres no load.She starts easy with a touch of the starter switch but she never used to till I started holding down the shifter in first when I start her.Now since playing with the shifter she will start all the time.Typically now I can start her with no choke and no playing with the shifter.If I shift and I dont release the shifter when I go through each gear she runs good and smooth other than 3rd which is shot.If i shift normal when I run trough the gears there is a surge where she seems to be missing.

[racerman_27410]

well then it sounds like you have transmission issues that need to be addressed.

maybe some bearings that are letting the tranny shift sideways and jam things up.


Kookaloo!

Frank

[Flying Scotsman]

2nd pops out all the way at high rpm under load but I can use it normally 3rd feels like it shifts in and out cant use it unless I am at constant low rpm.
I would like to have any needed tools on hand before pulling the motor and trans but plan on doing it soon.When she is running smooth the exhaust note sounds great just north of 4000 rpm and she runs great.

[Flying Scotsman]

Fixed it  I am not 100 % sure what it was because I unpluged and cleaned a lot of connectors I also cleaned the ground connector at the coils and I suspect that was the problem.
My tach still has a bit of a bounce to it at certain rpm but engine rpm dont drop like they were they stay constant.

[Flying Scotsman]

Just remembered I also had a lot of play in a shifter heim joint so I zip tied it so it wouldnt move around when vibrating.I need to cut the ziptie off to see if it was my gremlin.Probably not but anything is possible.

[bobmcc]

 The tachometer and speedometer on my 1986 fj bounced around when i bought the bike,The po had dropped the bike and the r/h mirror support was bent so it touched the instrument cluster.Also the instrument cover was touching the cluster on the l/h side. The cluster is mounted using rubber grommets so I think it has to be able to float a bit. I haven't had any bouncing since we bent everything back.

Bobmcc

[RichBaker]

Thank you I will take a look and see what I find in the a.m..I did look at your voltage drop post.I am just learning my way around the fj and electrics are harder than mechanics for me.If the negative from the battery goes to the motor then something must be going hot + and droping voltage shorting out at the shifter.Is there a ground strap going to the frame from the engine ?.I will go read the voltage drop post again ans see if i get any more out of it.
I could not get the 3rd screw out of the neutral switch should I continue and drill it out or am I wasting my time there.My foot and ankle hurt I need to fix this soon lol.

Been gone for the holiday.....

What I was trying to say is,  there is a ground cable that has broken or been disconnected and not reconnected and the shifter is now the "path" the electrons have found to get back to the negative battery terminal.... there are several ground connections to the engine and ignition system and if one or more are not connected, the electrons will find an alternate way back. Yamaha was pretty good about including a ground wire at the coils and if it was not reconnected,  it will cause this sort of problem.

Leave the neutral switch alone, it is not likely to be the cause...

[jykkeh]

Does anyone really know what is the problem with tacho?
Dont tell me something about ground or tachometer.
i have all tacho wires new and i also have new tachometer and after all my tacho is still crazy.
Dont tell me engine or coil ground,all are new.
When engine runs about 1000 rpm and then it jump about 1500 rpm goes down 1000 rpm and so on.. after 3000 rpm it seems to be okay.
Is it bossible that tacho get more pulse signal what is the real pulse?
And Thanks Of course

[andyb]

Is that an FZR600 dash?  Looks interesting there.  If it is, that tach is known to be a bit innacurate, and is in two steps, one error under 6200 and one over, different %'s.

Look for mechanical problems (vibration going into it), damping problems (within the gauge itself), and electrical problems (dirty signal, poor grounding, etc).

[jykkeh]

Yes and yes, but it runs well, but only 1000-1500 rpm it goes crazy, original tacho have same problem.

[JMR]

Yes and yes, but it runs well, but only 1000-1500 rpm it goes crazy, original tacho have same problem.

Is there any real definitive answer to idle tach bounce (or "twitch"). I experience this (only at idle and not all the time) and the tach is new, all connections/grounds perfect etc. It appears no one really has an answer once all the variables have been addressed.

[Dan Filetti]

Is there any real definitive answer to idle tach bounce (or "twitch").

Not sure.  Seems that I vaguely remember some folks have made sure that the ground, and coil connections, and coil grounds were all in good shape and this *may* have helped?  It's not a bad idea anyway.

Worth a shot, with only upside.

Dan

[JMR]

Is there any real definitive answer to idle tach bounce (or "twitch").

Not sure.  Seems that I vaguely remember some folks have made sure that the ground, and coil connections, and coil grounds were all in good shape and this *may* have helped?  It's not a bad idea anyway.

Worth a shot, with only upside.

Dan

All those factors have been addressed Dan. I don't know if it is related to the alternator somehow secondary to the low RPM or what. To bad I cannot use the Dyna 2000 tach drive lead.

[Bozo]

I also have a bouncing speedo, after repairing my fuel gauge, I'll be trying to fix the speedo. I already tried greasing the cable checking all mechanical parts, still bounces. Unlike the tacho which is electronic the speedo has a similar arrangement to the fuel gauge.
The following is the process I'll go through to fix the bounce (NOTE: I have not done this yet so I have no proof It'll work) -
1. remove speedo assembly
2. remove two screws on either side of tripmeter
3. Remove tripmeter
4. Lift the plastic lid with screwdriver, using syringe inject silicone fluid till full
Silicon fluid used on Toyota thermo fans