Vino XC50: Power drops when running full throttle By richg (Read 832 times)

[richg]

I've noticed this a couple of times now and was just wondering if it is normal.

After running my Yamaha Vino XC50 at full throttle for about 3 to 5 minutes the power will drop. It's not a gradual thing. It just seems to drop instantly to about half power. Is this some sort of protection mechanism that prevents one from running full throttle for too long?

[Alleyoop]

Well could be a few things happening:
1. It could be running LEAN and getting to hot
2. Your CDI could be rev-limited and when it reachs a certain RPM it retards the timeing.
This you can usually verify if after it drops the rpms you can then again bring it back up.
3. Your Carb bowl is not filling up fast enough or the fuel level is to low in the bowl and the Float needs to be adjusted to fill the bowl up a little more.
When this happens after it slows down you are not using as much fuel and the bowl gets a chance to fill up a little more.
4. The hard part is if something is getting to hot and cutting out on you due to getting to hot.
Alleyoop