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Before I jump into something that might not be doable, does anyone know if you can actually degree the cams on an 07 non ABS ST3?
 

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I can't remember for sure, but I don't think the cam pulleys have slotted bolt holes. So if that is the case, I think you would have to install pulleys with slotted holes before you could alter cam timing.

My Factory Service Manual DVD shows a procedure for checking the cam timing but it says nothing about adjusting it.
 

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Pretty sure all Ducs after 01 or so have the slotted pulleys. If not, then you just use off-set keys. Question is, are you degreeing the cams to something other than stock, or just ensuring they are at factory spec? If changing, I'm sure you know that it will required fueling after. To spec? Should be good to go. I am planning to do the same on the next service. I have the cam wheel and engine turning tool that you can mount a wheel to. I just need to source a metric dial gage and some kind of mounting system. I think I'm going for the flexible shaft with vice grip at the end deal.
 

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I can't remember for sure, but I don't think the cam pulleys have slotted bolt holes. So if that is the case, I think you would have to install pulleys with slotted holes before you could alter cam timing.

My Factory Service Manual DVD shows a procedure for checking the cam timing but it says nothing about adjusting it.
You can't see the slots in the slotted pulleys. They are behind a big steel washer. The slotted pulleys have three screws on the face. Solid pulleys do not have the screws.

The manual doesn't say anything about it because the reason for the slotted pulleys isn't really for adjusting the cams as much as they are for maintaining the current spec while tensioning belts. I think many use them for adjusting cam timing though, why not?
 

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Howdo!!!

Yep you can degree the cams (Pulley's are in 2 parts). Having changed the pulley's on my ST3 for a set of light weight ones, I matched them like for like and the cam timing was off :(
The process is not to hard to follow.......however getting accurate
measurements is a different thing.
The belts need to be set up correctly - 142Hz.
Valve clearances correct.
You then need:
Degree wheel (Makeshift pointer).
Engine stop (For getting accurate TDC).
Crank turning handle.
Micrometer
Feeler gauges.
Time!!!
The Factor micrometer has a little attachment that secures to the shim.
The main issue I found is holding the micrometer and lining up correctly with direction of the valve (Need to spend time and make a jury rig/get hold of the proper Ducati part).

These might be of use:
Video: How to Degree Cams : European Cycle Services

BikeBoy.org - Ducati Cam Specs

The ST3 Inlet specs are:
14 degrees before TDC
62 degrees after TDC
114 centre line.
Measured at 1mm lift.

I have set mine up as per these specs but bike is still not right, however the engine has high comp pistons, blue printed and when I asked the engine builder what specs he set the engine with he declined to tell me.....so it's back to him to get the cams dialled in (Which I shall check on completion for my own records) so that the bike can be re-mapped.

Best of luck.

Pablo
 

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Discussion Starter #6
Thanks for the info Pablo, exactly what I'm looking for.
Now to build up the courage....
 

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Howdo!!!

Just been in the garage playing again :rolleyes:
Re-adjusted both cylinders by 2 degrees.
12 degrees before TDC
60 degrees after TDC
giving me a centre line of 114 degrees
Not sparked her up as its a bit late and she's a bit loud for the old folks round here :D
Fingers crossed for tomorrow.
 

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Discussion Starter #8
Pablo, what year and model do you have?
 

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So I just finished my 6k mi valve and belt adjustment and would like to check the cam timing before buttoning her up but have run into a snag. While my previous ST4s had only one spark plug located directly inline with the piston, making it easy to check for TDC, the ST3 has two at odd angles.
I tried a 10-1.0 x 50mm bolt to use as a stop tool but it does not want to screw in to the plug hole enough to work as a stop. Don't know if this is because of carbon buildup inside the cylinder or interference with the valves and I certainly don't want to bend anything.


Anyway, I'm here looking for suggestions on how to accurately set TDC on the ST3 or perhaps a diagram of a functioning stop tool.

Tks
 

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Why not just use your dial gauge? That's the way most do it. Dial gauge in the plug hole, find TDC mark that posistion with the wheel and pointer.
 

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So I just finished my 6k mi valve and belt adjustment and would like to check the cam timing before buttoning her up but have run into a snag. While my previous ST4s had only one spark plug located directly inline with the piston, making it easy to check for TDC, the ST3 has two at odd angles.
I tried a 10-1.0 x 50mm bolt to use as a stop tool but it does not want to screw in to the plug hole enough to work as a stop. Don't know if this is because of carbon buildup inside the cylinder or interference with the valves and I certainly don't want to bend anything.


Anyway, I'm here looking for suggestions on how to accurately set TDC on the ST3 or perhaps a diagram of a functioning stop tool.

Tks

You can use the timing markings on the crank case, crank pulley, cam pulleys, insde belt covers.

1) Line up the dot on the crank pulley, with the hash mark on the crank case, just to the outside edge of the pulley. This will give you TDC on the H cylinder.

2) Release the belt tensioner bolts/pulleys so each cylinder so the cams can be rotated by hand.

3) On each cam pulley, there is a dot. Line that dot up with the arrow on the inside belt cover on each cylinder, one at a time. For the V cylinder the arrow is at about the 4:00 o'clock position.

4) On the left *side* of the head, there is an access allen head bolt, remove it, ie no oil lines attached, not a cover securing bolt.

5) Insert something that is rod like, and narrow enough to enter the hole in the cam shaft's left end, that will lock the cam into place, ie the cam has to be at the alignment marks for the rod like tool to lock into the cam. I use a 3" nail with the spike end rounded down. :)

6) Tension your belts.

7) Turn the engine over by hand several times to make sure there is no valve-piston interference.
 

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Nothing wrong with the method stryder explines. It's a varation of what's called out in the service manual. It's apparently how it's done in the factory at assembly as well. It is a bit of a coarse adjustment, however and the reason people go the next step which is setting up a dial gauge and a degree wheel so the cams can actually be set to spec. I'm on my phone so I do not have links from my home pc. I have a link showing the better way to do this, with pics! I'll post it when I get home.
 

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Here's that link:

CHECKING CAM TIMING ON 4 VALVE DUCATI

For a 4V, but easily adaptable. Don’t remember where I got it and I certainly take no credit for the great work done by the guy who did do it. Hope it’s helpful to someone here.

Pics load slow. Give it some time.
 

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Thanks stryder, all good information, but as 904 mentioned I'm looking for a more accurate method to dial in my degree wheel. Guess I should have been more specific and said piston stop tool. :eek:




SS904, Thanks! Great link, I bookmarked it for future reference.
I wish I could use my dial indicator through the plug hole, that's how I've done it in the past with my late lamented ST4s, but the acute angle of the plugs on the ST3 heads doesn't allow it. Maybe if I had some type of lever attachment for the end of the indicator, but unfortunately I don't own anything like that.
I didn't want to have to buy a commercially available piston stop tool, but may end up going that route. California Cycle Works sells one for $35.00 plus freight, plus the shipping delay. I was really hoping my bolt was going to work. :(
 

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Here's that link:

CHECKING CAM TIMING ON 4 VALVE DUCATI

For a 4V, but easily adaptable. Don’t remember where I got it and I certainly take no credit for the great work done by the guy who did do it. Hope it’s helpful to someone here.

Pics load slow. Give it some time.
Nice write up on checking the timing, but ultimately you still need adjustable pulleys or off-set keys to degree the cams. Are they available for ST3's?
 

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Nice write up on checking the timing, but ultimately you still need adjustable pulleys or off-set keys to degree the cams. Are they available for ST3's?
You already have them. Ideally, as it has been explained to me, the OEM adjustable pulleys are for use with the method you posted. Kind of setting to the assembly spec timing when adjusting the belts. Supposedly, if things need to move off the key machined in the cam and fixed part of the pulley, you should still use the offset keys. That way when you tension the belts (IF you do it like you described and not just a regular tension like most do), you will be able to maintain the cam specs you set with the offset keys. Seems crazy to me. Just make use of the provided adjustable OEM pulleys and don't mess with it again! Might screw up the next owner, but whatever!
 

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That's one HONKING 3 valver you've got stuffed into that SS chassis there Pablo!


Lots of nice stuff at that link, too bad it's all across the pond from me.


I got my 10mm bolt to work in the end though I had to modify it a bit. I was most concerned with bending a valve so I set up a couple small lights to shine through the plug holes and watched for possible collisions. Turns out the exhaust valve does cross the path of my stop tool so I was only able to use it when the engine wasn't on the exhaust stroke.


Incidentally, I found my cams to be 6 degrees retarded for the vertical and 2 degrees for the horizontal. Not as bad as some but well worth correcting.
 

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Discussion Starter #20
How about a detailed writeup?
Not for me, I'm an expert.....
But for those poor souls around here that need the help.:think:
 
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