Foolproof Cam Timing

COFFEE EDIT - Link to reference thread:
http://www.cafehusky.com/forums/showthread.php?t=3698




I posted up a little how-to on TT a while ago, but I didn't take pictures at the time. I had the head off recently to have my intake valves redone by Dave Hopkins (thanks, Dave!), and I took a few pictures to make that old how-to a lot clearer. Here ya go!



I finished reinstalling the head yesterday, and I have a couple more observations about assuring the cam timing is correct. It turns out you don't need to mark anything before pulling it all apart--all the marks are there for you already.

There are already some marks on the cam sprocket. The TWO marks on the gear portion of the cam sprocket align with the line on the head to indicate TDC.

Here is the tricky bit I figured out. When at TDC, the OTHER marks on the gear portion of the cam sprocket align with the marks on the cam gears!! The thing is, you can't SEE them aligning at TDC--your vision is obstructed by the head casting. Here's how to use those marks.

1. With the cams out, get the cam sprocket and timing chain reinstalled with the front chain slider and tensioner installed. You probably don't need the tensioner installed for this, but I wanted the maximum accuracy when verifying TDC. With the spark plug out, put something with a long, smooth, thin handle (like an hex wrench) into the spark plug hole so it is resting on the top of the piston. This is your TDC indicator.



Carefully move the engine through a few revolutions to verify the TWO marks align with the mark on the head when the hex wrench stops moving upwards. When you are satisfied that the cam sprocket and timing chain are properly installed, move on to step 2.

2. Use the kickstarter to carefully inch the engine to just before TDC.



When you do this, you will see another mark on the gear portion of the cam sprocket come into view. If the TWO marks are at the 12 o'clock postion, then this mark is at about 2 o'clock. You couldn't see it before since it was obscured by the head casting.

3. Grab the exhaust cam and find the mark on the gear.



While holding the exhaust cam in your hands, mesh the teeth together with the cam sprocket at the marks.



The tooth on one is marked to mesh with the valley on the other.



Now, you can't FULLY mesh the gears at the marks because the cam isn't aligned with its recesses in the head. But, with your hands tilting the cam up a little, you can mesh the edges of the cam teeth. (confused, yet? Good thing I don't write instruction manuals!) When you're sure the marked tooth meshes with the marked valley, "walk" the cam down to its recesses in the head without unmeshing the gears.



You're rolling the cam gear around the gear portion of the cam sprocket until the cam rests in its proper place in the head.



4. Snug down the exhaust cam retaining caps.




5. Carefully turn the engine over with the kickstarter a few times. There should be no interference.

6. Turn the engine over to just AFTER TDC. You should still see the mark on the gear portion of the cam sprocket that aligns with the mark on the intake cam. This mark is at about the 10 o'clock position relative to the two marks.

7. Repeat step 3 with the intake cam.









Snug down the caps.



8. Turn the engine over a few times and put it back to TDC.

9. Remove the left side cam caps so you can reinstall the oil line.



10. Torque the cam caps.



There! Guaranteed cam timing!!

This is the best most understable cam write-up I've seen in a very long time. Makes it clear, simple and idiotproof.

Thank You very much.

Phil

Tell the truth, you're doing this in the living room....while having a beer and watching Charlie's Angels, Full Throttle.

I drink only Zima when watching McG movies...

Sticky or move to the tech section. This is awesome. thanks!

This is a great write up. Thanks

thanks for the write up. one picture is worth a thousand words
I have one question.
Which cam cap goes where, I know there are two pairs of caps and they are numbered 1 to 4. Does it matter which goes where?

dirt rider have just rebuilt my 05 510so i know these have the manual in front of me now1 to the front left&2to the front right on your exhaust cam 3rear left&4 on your rear right on the intake cam and to make sure iam saying left & right from standing behind the bike looking at the handlebars

Front left: 1
Front right: 2
Back left: 3
Back right: 4
http://www.cafehusky.com/forums/showpost.php?p=35922&postcount=2

Huh? Are you saying the cam markers on the motors from the factory are off?

There are actually three factory marks (dots) on the larger cam idle gear (the one in the middle cog). Each cam has just one mark (dot)

On the larger cam the left dot lines up with the dot on the inlet cam, the centre dot lines up with the "V" in the cylinder head and the right hand dot lines up with the exhaust cam.

Ensure the middle dot lined with the cylinder head "V" in there with the piston at exactly top dead centre with all valves closed.

I rebuilt my head (TE510) and I was one tooth out on the cam chain and just 1mm away from TDC. The bike started fine from cold but was a bitch to restart and ran the battery flat. It ran fine but lost power.

Fix:
Valve cover off, remove plug, push bike to get piston to TDC. Take out of gear and view the middle dot on cam idle gear. Mine was just out of line. Remove cam tensioner and slip the cam cam one tooth forward.

Install cam tensioner and valve cover, kick over bike to make sure nothing banging :-) install plug and start.

Once all in line the bike starts first time, every time. The power is crazy.

has anyone ever seen the marks wrong from the factory? i'm doing a top end on my 06 TC510, i followed this to a tee, everytime i rotate around the piston hits the valves, i have double and triple checked TDC, valve marks, ignition timing, anyone with any ideas? the only thing i can think of the factory marks are off and i have no clue how to check this. looking close as the piston is coming back up on the stroke the intake starts to open, i pulled the intake cam and tried again but the result was the same on the exhaust.

Then it's likely you're using the wrong set of marks on the drive gear. It happens & it's easy to do because of how the marks are laid out and how the parts fit in the head........
Both sets of lobes should be pointing up & towards the center like an imaginary peak of a house roof (like Dfeckels last pic) when the piston is at TDC, if everything is timed properly.

i agree about the marks and this is why i think the factory paint marks on the dot are wrong, when everything is set the lobes are pointing strait up. i'm wondering what marks are the right ones to use

after 2 days and not needing a hair cut for 3 months, this application is not 100% fool proof, the marks for the cams on my 06 TC510 were not correct, but fear not there are other marks on the idle gear and cam gears that bring everything into the correct spot. if any one is interested i can reply!

Would it have been possible to check the 'cam marks' before tearing the machine apart and seeing that they were mis-marked and used this info to line the gears up correctly when re-building?

Any picks of the other 'marks' you are referring to?

lesson learned about looking before tearing apart, next time i will save myself the head ache. now about the marks, on the idle gear there are 3 sets of dots punched in, one of them has 2 punch marks, this is the TDC set mark, now rotate the engine counterclockwise and you will see another punch mark come into view on the idle gear. match this mark up to the painted punch mark on the intake cam gear and roll the cam into place. now turn the crank clockwise past the 2 dot TDC and another single punch mark becomes visable, this is the exhaust cam gear line up mark.