Question on YBR125 technical repair / maintenance

[MH071087]

I got a YBR 125 which just complete 10 yrs COE but i continue another 5 yrs.

 

However i want to repair or solve the bike problem which i occur in the past till now.

 

1. Tachometer (display RPM) doesn't work --> is it becos of the cable?

 

2. My top speed has drop from 110 to 90 over the yrs but i will wanna get back my top speed, hopefully ard 120rpm.

 

When i change to gear 5, the speed only increase from almost 80 to 90+ unless i fully throttle to the max, it will reach 100 only

What shld i do? (i heard by changing clutch plate will help abit)

 

Things i had change recent for servicing:

Spocket and chain

both bearing

air filter

spark plug engin oil (as normal)

back tyre

batteries

 

Any experience person can tell what to do ?

I don wanna end up tok by the service man in the bike shop

 

Thanks