Yamaha tach help

[Richsark]

Hi everyone, I have a Yamaha TACH to replace a broken analog tachometer. But I don't know how to adjust the yellow wheel? Because there's no pointer or Mark.
Could someone tell me what part of the yellow wheel I point at the required number.
Kind regards Richsark

 

[mjf55]

Richsark, It is set up specific for your motor. The numbers represent the number of magnet poles in the flywheel. Different Yamaha motors use different number of poles.
What is your specific Yamaha Model.

EDIT:
Got this from the internet written by a user named boscoe99 pertaining to Yamaha outboards:
Most electric start, two-stroke engines through 70 hp have 6 pole systems with an average output of approximately 6 amps. The 75 hp through 90 hp
2-stroke engines incorporate a single phase 12 pole charging system with an average output of 10 amps. The three phase charging systems have a stator with three lighting coils and a six magnet, 12 pole flywheel. All 115 hp and larger 2-stroke engines and 50 hp and larger 4-stroke engines incorporate this three phase system.Output varies from 10 amps on the 50 hp, 4-stroke engine to 50 amps on the 300 hp HPDI 2-stroke engine.

 

[Richsark]

Hi thanks for that my outboard is a 115hp 2 stroke, so it must be 12 pole. But if you look at the yellow wheel in the image, there doesn't seem to be a arrow or mark on it to indicate where to lineup with the chosen number. There is a raised part, but the wheel turns 360 in both directions? So I'm not how to set it, or which part to line up with the number 12?

 

[mjf55]

I looked at mine, ( well really a photo I took) and I have an arrow, so our versions are not exactly the same. Google search of the pn 6Y5-8350T-83-00 and I only saw one image that looked like yours. The person had a 200 hp and his was set so that the raised dot ( the one you have on 6 ) was on 12. So turn it clockwise 1 number.

Basically, I would try it, and if the RPMs look out of wack, try another setting. I dont think you will hurt anything, but I would turn off the ignition in between settings.
Let us know how you make out.