[Photo Feature]: 2008 Honda UniCorn Block Piston Probelm

Well, the unicon belongs to my dad originally.
We bought it 2008,Sep.

Here is some brief Stats of the bike:-

The bike has completed 53k.


From the date of buying this bike has been a beauty.No prblem at all.:D:D:D:D During these years,apart from the scheduled servicing these replacements has been made...


1. CHAIN KIT REPLACE at 25K ( service person told us to do this in 18K).
2. Battery change.
3. Rear Tyre replacement at 50K.
4. Shocker oil change ( outside from the A.S.S).

The bike do regular city tour of 10-20 kms per day and as well as Highway tours ( twice in a month).

recently for some days, specially after changing the rear Tyre; a noise coming whenever we are pressing the rear break pedal. First dad ignored but then the sound gradually becoming high enough, SO today I went to service center and told them about it; they took the bike and later they said that the rear brek pads to be replaced they further told me to change the disk break pads too and for a new chain kit.


They pointed out some other problems that mentioned in the bill.

1. Handle bar change. ( this was due to an accident happened around 5-6 months ago:()
2. recker ball or somthing.
and the most importantly
3. work on block piston.

the first two was not much of tension but the block piston problem made me worried. I asked them why works need to be done on piston, they said that whenever the RPM is around is more than 5000. the smoke is getting black and this indicates of piston problem.


after returning back to home I tried myself doing that; what I've found there is visible smoke whenever the RPM is more than 4500 the some is not really black but whitish.
and after lower the RPM that white smoke persist for 3-5 sec then it vanishes no smoke at all.


My question to the seniors is that really a BLOCK PISTON problem or the bike just need a new bottle of Mobil? and what to do?
please suggest.

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