How To Tear Down The Head & Cylinder

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Dabomb

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What you will need :

Allen Keys
8mm Spanner
9mm Socket
10mm Socket
Phillips Head Screwdriver
Your bike.
Long Nose Plyers or Cir Clip Pliers
Knocking hammer or wooden hammer handle.

Bolt types will vary from bike to bike.

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1. Remove the 3x bolts holding the front fender on with a 8mm Spanner.
1-14.jpg


2. Remove the oil cooler with a allen key.
2-8.jpg


3. Remove all plastics and seat bolts with a phillips head screw driver.
3-7.jpg

4-2.jpg


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Dabomb

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4. Remove rear mount for exhaust with an allen key.
5-2.jpg


5. Remove the 2x 10mm nuts from the head with a 10mm spanner.
6-2.jpg


6. Remove the bash plate mounts on either side of the cylinder ( only if you wish to remove the cylinder too)
7-1.jpg


7. Remove the 2x 10mm bolts holding the manifold and carburetor onto the cylinder head.
8-1.jpg



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Dabomb

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8. Remove the 4x head stud bolts evenly by loosening off the bolts in a diagonal manner. (top left->bottom right->bottom left->top right).
9-1.jpg


9. Remove the main cam bolt with a 10mm socket. (Caution the cam sprocket will have nothing but a gasket holding it on, remove the cover.)
10-1.jpg


10. With the cam sprocket cover off, remove the the head to cylinder mounting bolt with a 10mm spanner.
11-1.jpg


11. Remove the 3x cam sprocket bolts to remove the cam sprocket.
Have the engine in gear and 'crack' the bolt with a 9mm socket.
Remove the cam sprocket and let the cam chain sit in the head.
12-1.jpg


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Dabomb

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12. The head is now ready to come off, a knocking hammer or a wooden handle of a hammer can be used to free the gasket from the head and cylinder surface. Once this is done slide the head up the head studs.
13-1.jpg


13. Now the head is off remove the headgasket and seals, or you can leave them attached to the cylinder if you wish.
14-2.jpg


14. Remove the cam chain roller bolt with a 10mm socket, thus releasing the cam chain roller, let the roller sit fot the moment.
15-1.jpg


15. Remove the bolt holding the cylinder to the case with a 8mm socket.
16-1.jpg


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Dabomb

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16. Remove the bolt holding the other side of the bash plate on with a allen key.
17-1.jpg


17. Now the cylinder assembly is ready to be removed, it will be 'stuck' on with the base gasket so like the head, get a knocking hammer or wooden hammer handle and 'crack' the gasket loose so you can remove the cylinder.
carefully slide the cylinder up the 4 locating dowels, when the piston is getting close to poping out of the bottom of the cylinder have a hand ready to hold it.
18-1.jpg


18. Remove the 2x cir clips with a pair of long nose pliers or cir clip pliers (cir clips are found where the red circle is, in the photo below) from either side of the piston then remove the gudgeon pin(located where the green circle is, it was held in by the cir clips), the piston will now be free of the conrod.
19-1.jpg


19. Remove the old base gasket and seals and your done.
 

rossetti

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is it normal that your conrod is discoloured and all blue?? lol. nice thread though man should help heeps of pep
 
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Dabomb

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should be a silver/grey metal color.....
can only think of extreme heat turning it blue, if not i have no clue.
(i rhymed)
 

rossetti

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yeah thats what i thought too but i dunno. may be oil heatin up that much maybe?
 

rossetti

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ahh yeah it probly would. hows the bike go any ways i see you ridin round warners bay sometimes. wouldnt mind seein how it goes lol
 

Dabomb

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haha where u from? the bike goes preety well onroad, jsut need to gear it down a lil for maintained speed.
 

Dabomb

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i didnt rebuild it in the tute, but yes it still makes that noise after being rebuilt 2wice, once by me and once by Eastcoast50s and its going strong.
 

Speedy150

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whered ya find the NGK lead with coil? i seen them on ebay but cant find em anymore, did you notice any improvement with the NGK lead and coil???
 

Dabomb

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whered ya find the NGK lead with coil? i seen them on ebay but cant find em anymore, did you notice any improvement with the NGK lead and coil???

Not really, i think there more of a reliability modification!
 

fordrule

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when puttin the piston bak in the cylinder, will you need to clamp the rings to get the to fit bak in the cylinder?
 

fordrule

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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!!
 

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