Scooterotica

nellyboyo wrote:Ha, no I don`t have varitronic and I don`t think it is reading double as it will only go up to around 7k revs with a big handful .
It just gets there way to quickly .
It was sold a for a single cylinder 2 stroke but its not the end of the world if I can`t get it to work some shape .

That's good then. I may have misunderstood your original post. So it shows the right number but just the needle spins round to the correct point too quickly, yes? If so does it overshoot then settle back down?

Yes , I really need to damp the action down a bit . cheers

A koso rpm signal filter could tidy up the performance. Have you tried wrapping the signal wire on the HT lead ? What's the reading like there? Resistor or non resistor spark plugs can make a difference as can the routing of the signal wire keep it away from the magneto. I've had issues with my tachometer and I'm thinking of purchasing the filter

NO I didn`t try wrapping it around the HT lead . The old leads are quite thick and have metal connections on the end . I was guessing that a pulse from the green on the CDI would work , and it did. It would be something really thin for wrapping around the HT I would think .
I`m only guessing but the Koso unit is only a ferrite choke probably.
You can get clip on ones dead cheap if you want to try one of these first on yours .
I don`t think they`ll work on this type

I've never bothered thinking about this properly, so I can't give any advice on whether it makes sense or not, but it's a fact that MAY help you.

Anyway, most tachos that connect direct to the input to the coil (that I've come across) are connected to the negative or ground side not the 'pulse' side.

Intuitively I'd say that is wrong, but it works. It sounds to me like you've connected to the other side.

Give it a go; it'll cost you nowt.

So if I put it in parallel between the white and the red it may work ?
I`m away at work now so I can`t give it a go mores the pity as it`ll bug me for the weeks to come .......

I don't know what the white and red are, and I'm too lazy to go into the garage for a manual at the moment. But, I'd try 12v dc onto the Red and the black wire to the low tension side of the coil (either terminal).

If you don't like the result move the black wire to the other low tension terminal.

All of this is guesswork based on experience. If your house burns down as a result, I accept no responsibility.

Ha, don`t worry , The cave is made of concrete....

Where do you get the Koso filter from? I've a Koso GP MK1 analogue rev counter that reads odd readings...def for a two 2 stroke but I've an M-Tec box fitted, not sure if that will effect things? But does show about 12K when doing about 60mph and needle bounces around all over. In two minds whether to get shut of it!

I've got the wire wrapped around and insulation taped to HT lead approx 10 x wound round the lead, I was looking at other ways to attach it, but if people are confident that's the right way I'll leave it as is.