[LAV1000]

Be aware of temperature limits for optical sensors.
You might also checkout younger Yam's which might have decent crankwheel which fit your bike.

Quick google search for younger Yam's doesn't come up. Do you have a link I could go to at all?

Don't have a link for you.
It is also a part of the DIY principle.....

[PSIG]

If you start by searching "Yamaha trigger wheel", you get a lot of results from this

02-03_Yam_trigger_wheel.jpg (45.26 KiB) Viewed 497 times

to this custom design for Yam's. Click on the data sheet to see if the dimensions will work for yours.

Yam_12-1_Perf_Elec.jpg (39.81 KiB) Viewed 497 times

There are always 101 ways to do stuff. If it seems difficult, usually you just haven't looked at enough options.