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I just fitted a new cam chain, so I thought I would post a few pics to help people do the same task.
The part of the work I am focusing on is fitting the new chain onto the cam chain bottom sprocket.
Looking at earlier posts it seems a lot of people struggle with this and resort to grinding part of the casing to help fit the chain on the sprocket.
Maybe there is no choice on other bikes, from different years and different production runs, but my chain went on easy. It may just be a case of correct positioning and technique.
The bike is an L model, not H. Chain is a new genuine Kawasaki chain.

I left the crankshaft in the same place as when I removed the old chain.
It took me a while to remove the old chain and I thought the same sprocket positioning may help me get the new chain on easier.
It may help you to get the lower sprocket teeth into this position - at the bottom where it is nearest the casing. It may be a nice starting position for slipping the chain on.
Note the front cam chain guide has been pushed up, out of the way. The M8 cap head has been re-inserted in the end of the crank to allow the crank to be moved.


This is the way I placed the new chain over the back of the sprocket and trailing in front of the lower part of the sprocket where it is a tight fit between sprocket and case.


I then used an allen key to turn the crank clockwise a small amount and the chain just slid back into position on the sprocket. The chain is actually fully on the sprocket at the bottom in this picture.
I could not achieve this just by pushing the chain on the sprocket, I had to move the crankshaft slightly.
You can see how far the crank has moved by looking at the position of the pin in the end of the crank.
The chain was never jammed between the sprocket and case. It just fell back into position. Be careful not to jam your chain between sprocket and case.
I had to use very little force to turn the crank. No more force than normal crankshaft rotation.


With the hard part over I then just lowered a thick piece of wire down the cam chain tunnel, passed it around the chain, and back up out the top.
I then used this to pull the chain out the top of the engine, being careful not to let the chain slip off the sprocket at the bottom.


New chain fully installed.



It did take me a while to remove the old chain, and there were a few times where I thought It was impossible.
I tried all kinds of different positions with the free end of the chain.
In the end what worked for me was to have the chain outside of the engine and straight up from the crank leaving just that trapped bit underneath the sprocket.
I then turned the crank slightly with the allen key and the chain came out from under the sprocket, with the sprocket left in the position as shown in the first photo.
Again, the chain did not get jammed between sprocket and case. It just needs this slight movement of the crank to help it out.

Hope this helps someone.

I just wanted to confirm the correct cam timing. A bike I am working on appeared to be out by one tooth on the intake sprocket.
I have removed the sprockets and cam chain and arranged them as what I think should be the correct timing, as per the manual.
Obviously the crankshaft timing rotor 'T' mark (near the 'F' mark) has to be in line with the crankcase joint, and the marks on the camshaft sprockets have to be in line with the head surface.

your correct about the timing but retarding the inlet cam by a tooth is known to improve the midrange.

chris

OK....I am sitting here feeling pretty stupid right now......
I have just fitted my new cam chain and positioned the chain on the camshaft sprockets as above. Literally as per the diagram in the manual.
Positioned the 'T' mark in line with the crankcase split and lined up the exhaust sprocket mark with the chain side plate as shown in the manual. - That's the mistake - the chain side plate position is irrelevant isn't it!!
I got the sprocket mark as close to level as I could, thinking when the chain was tight and the cams in position the mark would pull around to be level with the crankcase top. - It didn't. I couldn't get the timing right.
The number of pins was correct from sprocket mark to sprocket mark, and of course the side plate position (as shown in the manual) lined up correctly with the inlet sprocket mark.

Instead of positioning the timing on the 'T' mark and looking how far it was out on the cam sprockets, I positioned the sprocket marks level with the cylinder head, and then looked how far out the crank mark was...
One tooth on the crank would do it.!!! That's when it hit me..Doh!

So does everyone already know this this but me? Ha. Or do the Japanese manufactures have a way of positioning the cranks, when the timing chains are installed, so that they line up as per manual, until someone comes along and fits a new one.?

A nice solution now would be to move the chain one tooth on the crank sprocket, but that would mean taking the chain off again.
So I guess I will just alter the chain position on the camshaft sprockets.

So the new approach would be.......
Position the crank at the 'T' mark.
Line up exhaust camshaft sprocket mark level with the head - attach the chain, ignoring side plate position, just focusing on getting the exhaust sprocket mark as level with the head as it can be.
Count along the chain to the 30th link and fit the inlet sprocket with its mark pointing at that 30th link.

Idiot
Idiot
I must not take manuals so literally......
Idiot
Idiot

Here are a couple of pictures to help judge if your cam chain is getting near the end of its life.

The cam chain tensioner only has a limited amount of travel to compensate for cam chain wear.
Eventually, after the cam chain has worn significantly, the cam chain tensioner rod will butt up against part of the casing.
At this point the cam chain will start to lose tension and will eventually start to run loose and rattle on idle, or just off idle.

The pictures below show the cam chain tensioner rod position with an old cam chain and then with a new cam chain.
So, if you suspect you have a worn out cam chain, here is the place to look first to check this.

Cracking post! Im making this a sticky!

Thread locked to keep things tidy.
If you have any questions please create a new thread.

Its so simple all you are doing is lining up 3 shafts. Set the T position on the crankshaft, next line up the exhaust camshaft, making sure the chain is tight between crankshaft and exhaust camshaft, then count the links between exhaust camshaft and inlet camshaft and bolt them down. Turn the engine over by hand a couple of times and check that the 3 marks line up. Hope this helps

very good help!
john

Hi guys , i need some help, i hope i didnt f*** my engine or something

i took my old cam chain off, and im waiting for the new one.
The reason i am changing the chain is because the tensioner blade is almost fully extended.
And when i tried to do my valve check (first time) the crank / rod ( with the "tooth wheel" in the end ) did not line up like it should, so i also suspect the timing is off or something.

Now i have the old chain off and i am feeling stupid, how do i install the new one ?
The wheel with the T mark, moved when i took the old chain out, so the engine is no longer at TDC.

I dont know how much it moved, But if i now put the T- marked plate on again, move the engine so its again at TDC will the valves be as they was before, so i can put the ned chain on ?

everything is out / off now, and how do i line up the timing and the crank rod , and then put the chain in so i can do valve check / adjustment ?

A little bit scared now ... (

I really hope you guys can help me !!

What you need to do is put the timing plate back on and rotate the crank until #1 and #4 are at TDC - this should correspond with the T-marks lining up with the crankcase partition joins (chapter 4-11 in H manual). you should also note that there is an F mark on the timing rotor, when you are at TDC for #1 and #4 this should be facing towards the rear of the bike. you can test for TDC with a bit of wire/long screwdriver down the bore...you will see it rise up and stop - TDC.

as your new chain is not on your valves wont be moving so you timing cannot be "out" at this point.

put the new chain on the crank and then guide the chain uptowards the top of the engine. check your T-mark against the crankcase sides and re-align it if necessary (remember you can only turn the engine one way) - i find its best to set the engine slightly before TDC, fit the chain, and then adjust it slightly to TDC.

once your chain is on the bottom, you need to fit your cams so that the timing marks are lined up with the top of the cylinder head and are pointing away from each other, your cam lobes for #4 should also be facing away from each other...#4 is at TDC on its compression stroke.

bolt everything down, fit your cam chain tensioner and turn the engine over slowly a few times to check your timing. from timing mark to timing mark there should be 31 pins (including counting where the timing marks are) and everything (t marks, timing marks) should be properly aligned as explained here.

if you do your timing and find you are 1 slot out i use a thin black marker pen to make a mark on the cam chain and a mark on the cam thats out...when i remove that cam i can then fit it back +1 or -1 slot as dictated by where the black lines are, a bit of oil removes the marker pen...then spin the motor again to check its all timed correctly.

I consider the manual to be a little confusing

Cheers for the guide, works mint

Has anyone got a copy of this thread with the pictures? Checked my tensioner today and it needs replacing. Any help appreciated.

Dan

Nope, but if you upload a pic of your tensioner I can see what needs doing...