Hi all,
a year back i purchased 1988 Rx100 which has given me lot of enjoyment.it was filled with power bcoz 120kmph was above normal. and i was getting a mileage of ~36 to 39 in city limits.
after some time i thought of rebuilding it to stock so i changed all most all parts (except handle bar, 16'' weel and head light). and at the same time my mechanic (who is from other city) insisted me to change the bore and piston so that will give more power and also more mileage. but while doing this he convinced me to change it to 110 cc shogun piston instead of Rx 100cc standard. blindly i thought, he is the mech so he knows more. so we converted it to 110cc with short bore to fit the piston.

every thing was done and when i rode my bike i noticed that there was a huge down in pickup but mech told me that its common for a new bore and i have to run it for 2000km in less than 40kmph, and now its almost 4000km i have run but still not found any good improvements.

some of the major problem which im facing is:

1. mileage decrease to 28~30max
2. huge vibration starts from engine (inside) after crossing 55kmph
3. speed at each gear: 1st-15km, 2nd-25, 3rd-42,4th-60
4. engine is getting heated very quickly.
5. if try crossing 80 i feel like engine may burst.
6. poor acceleration.

i love my bike very much. but from last 4 to 5 months i am not able to feel the power of the RX. and i am worried and afraid of going to the mech as they will try all new new R&D with our bikes. i have a feeling that most of the probem can be solved if i tune/ changing the setting of carb (just a wild guess)

some more info of my bike:
maintains very neat, regular services, cleaning
40ml oil to the tank for a L petrol.
regular smoke from exhaust ( he had also changed it to used rx100 original as mine had many dents)

i need your opinion and advice so that i can bring my bike to normal and also can anybody suggest me a very good mech who knows in and out of the Yamaha RX anywhere near by South Bangalore.