guys,
i am going to do decarbonising on my zma soon and was wondering if i could increase the compression on the engine.im kinda confused as to which gasket should be removed .is it the cylinder head gasket (the copper one) or the base gasket of the block .will it advance the cam timing?

very technical questions only gurus can help.. ravi??

any 4 stroke bike going for combustion chamber follow the same principle.
the head is removed and the combustion chamber along with piston top.
while assembling the head the head gasket is changed along with 3 'o' rings in the head are changed. the timing is matched and fitted. never open the bore while DE carbonizing as the rings and liners are properly set together. opening and refitting will cause compression to leak past rings. open the bore only when their is need for boring or change of bore.
no de carbonizing will not increase the compression ratio rather it will decrease as build up of carbon decreases the combustion space and increases the compression ratio. this is the reason for knocking when excess carbon builds up.
do not advance the cam timing.
to check whether the timing is correct at the time of assembling use the following steps:-
1. check the magneto is at timing mark through the peep hole.
2. see that the piston it at top by checking both the rocker arms are free or by inserting a thin screw driver through plug hole.
3. check whether the mark on timing sprocket match with the mark on the head cover.
if the timing doesn't match then it will give serious troubles. most of the problems are caused by improper timing.

BUDDY,
i know that decarbonising the engine will not increase the compression!! from what i have read from other forums on this topic says the shaving the head by a mm or two would increase the squish area on the combustion chamber. i heard that this can be done in two ways 1.)either shaving the head or
2) by removing the gasket
what i nead to know for sure is which gasket should i remove ? is it the really the head gasket or the base gasket located between the crankcase and the cylinder?

if the compression is increased (if the head is shaved /gasket is removed)there would be a small slack in the timing chain so i was wondering if this slack would increase/retard the timing)

i inspected the battery of my bike and to my surprise the case is rusted with some white formation. is that gonna harm it or its normal?

whitish powder is sulphur from battery. too much of it indicates lower water level in battery for long period.
get it cleaned asap, put some distilled water in battery to max mark in each cell ( all 6 of them) . inspect the battery compartment for heavy rusting. Normally it remains strong enough.

Avoid direct skin contact with battery sulphur deposits.
go to a mechanic if required, just make sure he fills in distilled water only. they usualy put tap water. buy distilled water from any battery shop or Petrol pump.

thanks for the info.

in fact i myself fill the battery water after getting didtilled water bottle from petrol pump.

i forgot to thank you for your help.

ODO problem

Guys i am facing some crepy sound problem with my analogue meter as it creates hell lot of sound when the tyres are in motion i removed the speed wire and the sound was gone ...
Please advice what could be the possible problem

Time to change speedo cable. Mine was making noise too. Replaced cable. Noise gone . Got two extra cables now .. hehaw!

Allrite Bro will do that tomorrow just one concern how can a cable make a sound as that noise is coming from meter itself...any tech reason please lemmie kno for my curiosity

mmm..you got a point. Mind was just at the opposite end, i.e. on the wheels. The noise was coming from the joint where the cable meets the wheel. The defect in my case was with the cable. The same can also be true at the other end where the cable meets the meter. Hopefully this is the case as changing cable is simple and inexpensive. Also it wont hurt to simply clean them with spray like WD40 or similar.

hmm thanks for the quick response bro...it seems the assembly which runs the speedo through the cable is at fault will need to open up the merer to repair it...any idea of possible repair cost or it needs to be changed as it will b expensive anyways

It can be the Plastic gear where the cable connects to the wheel, if you have to change that, it will cost 8 bucks for the plastic gear, and labour extra should be 20-30 bucks. I would say, get it opened and get it checked.

@anmol_1990: This is common with most bikes&cars, even happens with MF batteries so nothing to worry as long as its not too much.
Put some petroleum jelly (vaseline) on the battery terminals.
Most of the battery shop guys do this to cars.