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Discussion Starter #1
Hello Gentlemen!
I am doing my first valve check/belt replacement on my new-to-me 2009 1198. I rented the tool kit from ducatitoolrental to do the work. Luckily, all of the clearances were in spec, so no adjustment needed for now.

My concern however, is that in the instructions provided with the tool kit, it shows the cam lobes on the openers pointing straight up when at TDC on each cylinder. Mine are not. On the vertical cylinder, they are both approx. 45 degrees outward, and about 45 degrees inward on the horizontal cylinder. The bike runs good, which I can't imagine if the cam timing were truly off that much. I attached a couple of pictures, the first is the horizontal, the second the vertical, both at TDC compression stroke. Just want to be sure I'm ok before I start bolting things back together. Thanks!
 

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I've never seen the instructions from ducatitoolrental but I'll assume that they had the belts off to do the measurements so you can move them @ will.

What are the measurements now?
 

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Discussion Starter #3
All of my clearances were between .003-.006", so I'm good there, but their instructions said that at TDC, the opening cam lobes would be straight up. That is my only concern.
 

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At TDC on either cyl/piston neither lobes are straight up when the belts are on and cam timing is proper, they are either pointing inwards or outwards, probably they meant "remove the belts, put the piston that you are working on on TDC, point the cam lobes straight up and check valve clearances"

OP int @ .004
OP ex @ .006
CL both @ .004/.006

This is a good set up for a street bike, if you have a .003 @ an OP ex I'd adjust that.

Good luck!
 

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I'm not sure if this is helpful, but you need to remember that a four stroke engine has two different top dead centres. Only one is the power stroke when both valves are well closed.

On the 'other' TDC the valves will be 'rocking', with the exhaust valve just closing and the inlet valve just opening.

This is the period referred to as 'valve overlap', and is the area of valve timing Ducati changed when they went to the so-called 11 degree engine. (This was reduced from 43 degrees or so in the interests of emissions).

So only every second TDC is the same as regards cam position. The cams turn at half engine speed for this reason.

So only one cylinder fires on each revolution. This is referred to as a 270/450 firing order, with the 90 degree offset between the cylinders.

Possibly not what you were asking, but a better understanding of the process is helpful if you are doing your own work.
 

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Pat, clearly a person who asks suck questions have a lot of reading to do in order to understand how an engine works.
 

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I had the same problem, as long as they are pointing in the direction of up or more so at each other at a angle.

So in my opinion normal..
 

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Discussion Starter #10 (Edited)
Pat, clearly a person who asks suck questions have a lot of reading to do in order to understand how an engine works.
Devimau-
Let me first say that the only thing new to me about motorcycles and engines is Ducati, as in, this is my first Ducati. I have rebuilt both two stroke and four stroke engines from the bottom up numerous times and have been working on bikes for over 20 years. All four stroke engines that I have experience with, however, have conventional valve spring setups unlike what Ducati uses with the opener and closer arms.

In my limited time on this board, I have read numerous posts similar to yours, quickly jumping to the assumption that the person has no idea what they're doing.

I would politely suggest that you not make a statement like "clearly a person who asks suck questions have a lot of reading to do in order to understand how an engine works" when you don't have enough information to back that statement up. Isn't the whole purpose of forums such as this to be a place where people can feed off each other's knowledge and collectively increase the satisfaction we all get from working on and riding our bikes? The written information I was working with had a flaw, and I was just double checking. Your responses earlier on were helpful. Not sure where we went wrong :)

Even though I already had the knowledge of how cams operate, at least Pat's response was informational and non-presumptuous, which I can appreciate.

Cheers.
 

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Court Jester
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I'm with ya tallguy
 

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It may be that the info you were working with was somewhat generic - not specific to the Testastretta engine.

If you look at the angle the rockers engage with the cam that might explain why the cam lobes don't point straight up at TDC.

Basically you need the cam lobes pointed away from the point where they engage the opening rockers to check their clearance.

But if there is any variation in that clearance through the cam's base circle, the clearance is obviously most crucial at TDC on the compression stroke, or just before TDC.

It is at the point of creating compression that the valves need that optimal clearance from the rocker/camshaft.

I'm sorry if any of our explanations were too simplistic. Of course it isn't always clear how much experience folks asking questions like this have. It can go either way..
 

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Devimau-
Let me first say that the only thing new to me about motorcycles and engines is Ducati, as in, this is my first Ducati. I have rebuilt both two stroke and four stroke engines from the bottom up numerous times and have been working on bikes for over 20 years. All four stroke engines that I have experience with, however, have conventional valve spring setups unlike what Ducati uses with the opener and closer arms.

In my limited time on this board, I have read numerous posts similar to yours, quickly jumping to the assumption that the person has no idea what they're doing.

I would politely suggest that you not make a statement like "clearly a person who asks suck questions have a lot of reading to do in order to understand how an engine works" when you don't have enough information to back that statement up. Isn't the whole purpose of forums such as this to be a place where people can feed off each other's knowledge and collectively increase the satisfaction we all get from working on and riding our bikes? The written information I was working with had a flaw, and I was just double checking. Your responses earlier on were helpful. Not sure where we went wrong :)

Even though I already had the knowledge of how cams operate, at least Pat's response was informational and non-presumptuous, which I can appreciate.

Cheers.

So If you don't have a lot of experience on how an engine works, in this case a ducati engine, then you have a lot of reading to do.....what's wrong about that?

I'm sorry if I did hurt your feelings but that was not my intention, I try to help people as much as time permits and most of the time (like in this case) even without getting a simple "thanks" back in return (you would kind of expect it out of politeness, but whatever) and I'm not there searching people's history and trying to suggest them what to do so instead of trying to play people's advocate and pointing out my behavior (that by the way I'm not a confrontational guy and have no history of having issues with other members) I'd suggest that you look at your actions first before you point fingers.
 

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Discussion Starter #15
So If you don't have a lot of experience on how an engine works, in this case a ducati engine, then you have a lot of reading to do.....what's wrong about that?

I'm sorry if I did hurt your feelings but that was not my intention, I try to help people as much as time permits and most of the time (like in this case) even without getting a simple "thanks" back in return (you would kind of expect it out of politeness, but whatever) and I'm not there searching people's history and trying to suggest them what to do so instead of trying to play people's advocate and pointing out my behavior (that by the way I'm not a confrontational guy and have no history of having issues with other members) I'd suggest that you look at your actions first before you point fingers.
My feelings were not hurt nor do I have any hard feelings toward you. Hopefully that feeling is mutual. Since the words we type on this board lack tonality and all of the things that go along with face-to-face interaction, possibly I just misinterpreted your intentions. I do appreciate the information given in this forum. That's why I came here! For what it's worth, the bike is back together and running good again.

Thank you all.
 
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