How To Tear Down The Head & Cylinder

fordrule · #21 (**permalink**) 13-01-2009, 04:34 PM

hey i need a quik reply,
im up 2 the part wher u crack the 3 cam bolts, but the cog keeps movin, even when its in 1st or 2nd. How do i hold the kog still??????????

please reply asap!!

Dabomb · #22 (**permalink**) 13-01-2009, 04:47 PM

ahh ok, have it in 1st and get it to TDC where it gets compression and you've gota give it a real quick twist and it will come undone, if ur struggling you can try:

jamming a flat blade screw driver in the magneto to hold it
or
have someone hold the rear brake on while the bike is on the ground

fordrule · #23 (**permalink**) 13-01-2009, 04:48 PM

cheers 4 that will try!

duongyy · #24 (**permalink**) 13-01-2009, 07:02 PM

omg Dabomb you are a legend !
my cam chain roller bolt came off the other day and the roller is probably flying around, since uve posted this up i'll get to the roller easily and get it all fixed up =]
ur a legend (Y)
btw do i need to get new head gaskets etc after i tear it all down?

mike.

china boy788 · #25 (**permalink**) 13-01-2009, 07:26 PM

hey,, jst checking but in pic 12 thats the cam where the 3 bolts go??

fordrule · #26 (**permalink**) 13-01-2009, 08:58 PM

hey, i got the head off, i have a few questions n need quik replys!!
firstly, the cap with the 4 bolts on top of the head, mine has a ripped gasket, will that cause smoke 2 blow, is it worth replacing?

how can you tell if rings are gone without taking off the actual cylinder??? the actaul
cylinder itself looks perfect not a mark in it. but the head of the piston is covered in black crust. n so ar the valves, dad reckons they are shot, how can u tell if they are crap? (btw my bike blows heapsa smoke)

also will i need to reset the timing chain? coz i wanted to see in the cylinder without
takin off cylinder, put bike in nuteral n gave a tiny turn with kick start. will i have 2 reset the timing? is it hard? n how do i do it?????

also im havin trouble tryin 2 put cam cog bak in, it seems as if chain is 2 small??

pls reply asap!!!!

Dabomb · #27 (**permalink**) 13-01-2009, 09:00 PM

Quote:

Originally Posted by duongyy

omg Dabomb you are a legend !
my cam chain roller bolt came off the other day and the roller is probably flying around, since uve posted this up i'll get to the roller easily and get it all fixed up =]
ur a legend (Y)
btw do i need to get new head gaskets etc after i tear it all down?

mike.

haha thanks bro, yeah you should replace the head gasket after you tear it down.
the other gaskets mite not need replacing but its good practice to do so.

Dabomb · #28 (**permalink**) 13-01-2009, 09:02 PM

Quote:

Originally Posted by china boy788

hey,, jst checking but in pic 12 thats the cam where the 3 bolts go??

you are correct, cam sprocket bolts to the camshaft with the 3 bolts you mentioned.

Dabomb · #29 (**permalink**) 13-01-2009, 09:14 PM

Quote:

Originally Posted by fordrule

hey, i got the hea off, i have a few questions n need quik replys!!
first, the cap with the 4 bolt on top of the head, mine has a ripped gasket, will that cause smoke 2 blow, is it worth replacing?

how can you tell if rings are gone without taking off actual cylinder??? the actaul
cylinder itself looks perfect not a mark in it. but the head of the piston is covered in black crust.

also will i need to reset the timing chain? coz i wanted to see in the cylinder without
takin off cylinder, put bike in nuteral n gave a tiny turn with kick start. will i have 2 reset the timing? is it hard? n how do i do it?????

also im havin trouble tryin 2 put cam cog bak in, it seems as if chain is 2 small??

pls reply asap!!!!

its good practice to replace ripped/broken/squished gaskets.
it will leak small amounts of oil which may burn causing smoke.

signs of 'gone' rings are:

low compression (doesn't take as much to kick it over)
blowing blue smoke (oil getting passed the rings)

all pistons preety much have black carbon deposits, but carbon crust on the piston would point to oil getting passed the rings.

when you remove the head the engine needs to be re timed.

timing is a matter of aligning the timing (TDC) mark on the cam sprocket with the notch in the head

AND

aligning the timing mark which is TDC on the magneto with the mark on the case around the magneto.

it is good practice to set and fix the magneto timing to TDC then with then rotate the cam sprocket inside the cam chain till it aligns with the notch on the head then bolt it to the cam in that position.

you must have the head full bolted down and tight when doing the timing,
if you find the chain is too small still, release the cam chain tensionor which is located left of the oil drain bolt under neath the engine, careful there is a spring that will pop out and a small ammount of oil will leak from there also.

fordrule · #30 (**permalink**) 13-01-2009, 09:27 PM

ohk thanks for that, i have some more questions aboout the timeing, but ill ask you later,
coz first i want too know how to tell if rings are gone?
do i have to take cylinder off? if so, what do i look for too tell if rings are blown?
other wise how can i tell with just the head off?
as u can probs tell so far im pretty new to this.

please reply quik, cheers!

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How To Tear Down The Head & Cylinder

How To Tear Down The Head & Cylinder

Posted in Motor Tutorials