[AbstractSpaces]

Hi all, I've lurked around this forum for years when looking for advice. I was hoping my first post could be something positive like posting pics of the new paintjob I have planned, but unfortunately instead I come asking for help.
I have a 2014 Daytona 675R that I'm checking the timing and valve clearances on. Bike has about 35000km on it. So I'm putting the camshafts back on, I have the timing plate locking them in place and the pin inserted into the crank ensuring everything is lined up for TDC so I can reset the timing. And as I tighten down the bolts on the ladder cap something goes SNAP.
I look over and half of the slot in the exhaust camshaft has broken off. I fish the broken piece out of the radiator fan, and after freaking out for a bit I give the shaft a look over and think it's probably still usable if I can ensure it's correctly lined up when setting the timing. I take the ladder cap back off and try to line the shafts up again, being extra careful this time since it would seem they weren't sitting properly in the journals when I tried the first time. But the damn things won't line up.
The intake camshaft won't rotate around enough to line up with exhaust because the lobes for cylinder 1 make contact with the tappets. Hopefully my photos below will illustrate this well enough.

I thought maybe the shims were way out of whack so I removed them all to give more clearance and checked again, but they still won't line up without the intake cam starting to press down and open the valves on cylinder 1.
So I'm wondering if the intake shaft is warped, because I can't think of anything else that would cause things to fall so far out of alignment. Can anyone here offer any insight? Thanks in advance.

 

[samwise_i]

Take a picture of the gear/chain side.

 

[AbstractSpaces]

Here's the sprocket side. Not much to note here because I've completely removed and reinstalled all this stuff with the intent of resetting the timing (I'm following the manual procedure and have all the tools including the stupidly expensive 0.6nm torque limiter). The problem isn't with the chain or sprockets because even with them removed, the slots can't be lined up as per my first post.

 

[AbstractSpaces]

The manual says that the intake valves open 27.49 degrees before TDC, so it make sense that the cam lobe would be pressing down on the tappet when piston 1 is at TDC (assuming it is TDC on the intake stroke, which it looks to be given the position of the lobes). But if that's the case then how am I supposed to insert the plate across the two shafts without it snapping like it did?

 

[samwise_i]

The exhaust cam might have slipped with respect to the timing gear. Are the bolts that mount the timing gear to the cam tight?

 

[ramnakhle]

Hi all, I've lurked around this forum for years when looking for advice. I was hoping my first post could be something positive like posting pics of the new paintjob I have planned, but unfortunately instead I come asking for help.
I have a 2014 Daytona 675R that I'm checking the timing and valve clearances on. Bike has about 35000km on it. So I'm putting the camshafts back on, I have the timing plate locking them in place and the pin inserted into the crank ensuring everything is lined up for TDC so I can reset the timing. And as I tighten down the bolts on the ladder cap something goes SNAP.
I look over and half of the slot in the exhaust camshaft has broken off. I fish the broken piece out of the radiator fan, and after freaking out for a bit I give the shaft a look over and think it's probably still usable if I can ensure it's correctly lined up when setting the timing. I take the ladder cap back off and try to line the shafts up again, being extra careful this time since it would seem they weren't sitting properly in the journals when I tried the first time. But the damn things won't line up.
The intake camshaft won't rotate around enough to line up with exhaust because the lobes for cylinder 1 make contact with the tappets. Hopefully my photos below will illustrate this well enough.
View attachment 259955
View attachment 259956

I thought maybe the shims were way out of whack so I removed them all to give more clearance and checked again, but they still won't line up without the intake cam starting to press down and open the valves on cylinder 1.
So I'm wondering if the intake shaft is warped, because I can't think of anything else that would cause things to fall so far out of alignment. Can anyone here offer any insight? Thanks in advance.

Hi
I realize this is an old post but I had the same problem and broke my intake camshaft in exactly the same way.
I figured it out and replaced the camshaft.
The problem is with the tightening sequence on the cam ladder.
Let me know if you still haven’t solved it.


Sent from my iPhone using Tapatalk

 

[Dirk777]

Hi,
the problem is not with the tightening sequence. You chose the "wrong" TDC for mounting the cams. Because of that I recommend not take apart the sprockets!
On a 4-stroke engine you have 2 different TDC because the crankshaft turns 2 times (720°) to have a full cycle completetd. The first is the firing TDC, when both valves are fully closed and the cams will show the play; the second is the end oft he exhaust stroke, when both valves are slightly open due to the overlap. Every 120° of crank rotation one piston is in TDC, every 240° one cylinder is firing. The firing sequence is 1-3-2, to achieve a smooth engine run. If you're working on the cam-drive you have to choose the firing TDC of the first cylinder, when the valves of cyl. 1 are fully closed.

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[ramnakhle]

It doesn’t matter which TDC it is because in both cases the piston will be at the top of the cylinder. Doesn’t matter which valves are open or closed.

What happened is because of the tightening sequence because at TDC in a 3 cyl engine BOTH intake and exhaust valves are SLIGHTLY open. There’s a small degree of overlap between the two.

Go to the how to section I made a detailed PDF explaining the problem and correct procedure.


Sent from my iPhone using Tapatalk

 

[Far Canal]

Hi
I realize this is an old post but I had the same problem and broke my intake camshaft in exactly the same way.
I figured it out and replaced the camshaft.
The problem is with the tightening sequence on the cam ladder.
Let me know if you still haven’t solved it.


Sent from my iPhone using Tapatalk

It doesn’t matter which TDC it is because in both cases the piston will be at the top of the cylinder. Doesn’t matter which valves are open or closed.

What happened is because of the tightening sequence because at TDC in a 3 cyl engine BOTH intake and exhaust valves are SLIGHTLY open. There’s a small degree of overlap between the two.

Go to the how to section I made a detailed PDF explaining the problem and correct procedure.


Sent from my iPhone using Tapatalk

Posting a link to your PDF would likely be much more helpful to people than "let me know if you still haven't solved it" and "go to the how to section".
Just saying.

 

[ramnakhle]

Posting a link to your PDF would likely be much more helpful to people than "let me know if you still haven't solved it" and "go to the how to section".
Just saying.

Hello FC
Sorry just saw your reply I was out for a few months.
It said got the the how to “I made a detailed pdf…” and it’s in the post.
I didn’t just post a link here because the other post has all the details and describes the problem as well as the solution. It also has a link to my original post when I broke the camshaft same way as OP did.

Anyway I should have posted a link to the other post in the how to’s.
Here it is



HOW TO: Complete valve train inspe...-inside..252171/&share_type=t&link_source=app


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