Weird Noise

[Aerox_03]

(Minarelli Horizontal) Aerox

ok when my engine has been running a while, when the revs start to pick up there is a slight grinding noise, like if you imagine 2 metal disks touching whilst spinning. it only happens for about half a second, it also sometimes does it when the revs are goin down aswell.
Wondering what it could be?

Any response appreciated.

Sam

 

[Adz*magic-aerox]

this might be the problem.
(probably don't do it up well), it could be your cooling fan on the front pully is lose, this is because the spline,little teeth bits on the inside have worn down and it lets the cooling fan rock side to side. watch out it doesn't losen the nut off and then shred your crank.
Adam

 

[Aerox_03]

so is it just a case of tightening a nut or will it require more?

 

[Adz*magic-aerox]

take the side case off and try and move the cooling fan if it moves then either check weather the splines have gone if so get another one or tighten it up well.