How To Tear Down The Head & Cylinder

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Dabomb

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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
 

duongyy

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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.
 

fordrule

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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??:confused:

pls reply asap!!!!
 

Dabomb

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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

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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??:confused:

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

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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!
 

Dabomb

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taking the cylinder off and exposing the rings will tell you much more the condition of the rings.
you would look for scoring on the rings, scrapes, even big scratches/scoring on the bore.

with head cylinder on, a good test would be to put oil around the rings and wind the kickstart around so the piston goes up and down and see if the rings keep the oil above the rings.
 

china boy788

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if u were u upgrade ur cam to a g2 one,,, how wood u get in out???? do u gotta take off the the head, or jst u like slide it out????
 

fordrule

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sorry mate im getting realy confused, wats scoring?

can you tell me if theres a simple way to tell if rings are gone?

if i give it a wind around should i have it in nuteral?
what do i do about havin the timin chain? its just hangin out does it mater ?
how do u mean put oil around the rings? take out piston? or just rub it around the
rim, ie the part near where the head sits on the gasket?

is it hard to take the cylinder off, then put it bak on? wat do i need 2 know when puttin bak 2 gether?
 

Dabomb

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if u were u upgrade ur cam to a g2 one,,, how wood u get in out???? do u gotta take off the the head, or jst u like slide it out????

you take the head off and remove the rocker arms then remove the cam then pull the cam out.
 

Dabomb

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sorry mate im getting realy confused, wats scoring?

can you tell me if theres a simple way to tell if rings are gone?

if i give it a wind around should i have it in nuteral?
what do i do about havin the timin chain? its just hangin out does it mater ?
how do u mean put oil around the rings? take out piston? or just rub it around the
rim, ie the part near where the head sits on the gasket?

is it hard to take the cylinder off, then put it bak on? wat do i need 2 know when puttin bak 2 gether?

the rings will look scratched.

yes in neutral.

just let it hang but dont let it get caught on anything.

rub around the rim of pistion.

its not very hard to take the cylinder down, you will need a new bottom gasket, just remember how u took it down and but it back how it was.
 

fordrule

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ohk so the rings will look scratched, so does that mean the bore should have scrapes in it? coz mine is smooth as, wich is why im hesitating to take cylinder out, coz i dont think rings r worn coz the bore isnt. Is it possible the rings are scratch, n bore still be good?
sorry bout this, i just dont wanna do more work then i have 2, n risk ruining my bike more.

ohk so i put oil around piston rim, put gasket n head bak on, tighten it, then kick it over in nuteral, with or with out the spark plug screwed in (discontected obviously)?
or do i leave the head off? n do the rest that i stated?
 

Dabomb

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i think it is possible to have scored rings but not scoring on the bore.
did the engine have symptoms of blown piston rings before you pulled it down?

leave the head off and pump the kickstarter in neutral, look to see if the u placed around the rim of the cpiston gets pushed up out of the cylinder it gets passed the rings.
 

fordrule

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yes the engine was blowing s*** loads of white smoke be4 i stripped the engine down.

the oil did seem to get passed the rings, but i took cylinder off nyway. from what i see, the piston rings are in pretty good condition, n the cylinder looks perfect.

what could be causing the smoke? i found that the cam cover gasket was ripped, i might hav done it wen takin it off. I also found the cylinder gasket was ripped, the one between motor n cylinder, not between head n cylinder, but i might have done it when removing it. n the valves in the head were black as n cover in black crust.
what should i do?? what could be wrong???:confused:
 

fordrule

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when i replace the gaskets, do i need to use nything to get it to hold on, like glue or oil?
 

Dabomb

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nah man the gasket is all u need, clean the joining surfaces to so theres no crap
 

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