I hav a Yamaha RX 135 4 speed (2000 model) for last 10 years (Actually, I am in love with her for a long time). I do all service and necessary checkups by own. Engine has been done (bored) two times and this time (in March2010) I fixed the new slip (as mechanics call it) with standard size piston. It ran well for 4 months, but few days earlier I saw oil leaking from cylinder head. I opened cylinder cap and when I refixed, 3 out of 4 bolts (studs) got slipped. Two out of 4 studs were already oversized earlier.
My concerns are: Can an oversize stud be fixed again on the same or I need to buy a new/used cylinder kit?
Can anyone elaborate on where I can get new or used cylinder kit in Delhi/Noida?
Thanking you in advance for your kind suggestions.

Some necessary data about my RX 135:
Kilometers done: More than 65k.
Year of manufacturing: May 2000
Fuel Efficiency: 35-40 Kpl on an average speed below 60. (It falls down after speeding over 60+).
I have attached an image of my bike for a review.



Comment