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Discussion Starter #1 (Edited)
Here's my problem. I remember when I did the timing last time, the intake valve pulley rotated all the way around when the piston is in TDC. I'm trying to align the marks (made a long time ago so it'd be easy to remember the next time) and now the pulley isn't spinning all the way around when the piston is at TDC so that I can alight the marks. I remember it rotated 360 degrees freely (with tension of course) when the piston was at TDC because I remember my hand was slipping and the dot on the pulley rotated all the way around and then I'd try again.

I'm inclined to remove the head again and see what's going on.

This time around, I had the bike on 1st gear and I used a crankshaft turning tool to move the piston to TDC.
Unless...I'm supposed to match the marks when the piston is on not on TDC.



my previous attempt in timing,

https://www.youtube.com/edit?o=U&video_id=rwpBPZeiQGI



On this video @10minutes and 24 seconds (
).

The tech says the vertical piston is now 90 degrees past TDC. And he tried to spin that intake valve and it stopped.
His mark never made it past the matching mark.

Is that intake valve really "NOT" supposed to rotate 360 degrees when spinning it manually?


I just wanna :BoomSmilie_anim: 749
 

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To make a long story short;

The marks on the pulleys apply when the horizontal is at TDC, not when the vertical is at TDC.
Set your horizontal at TDC and work from there.
 

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To make a long story short;

The marks on the pulleys apply when the horizontal is at TDC, not when the vertical is at TDC.
Set your horizontal at TDC and work from there.
Thats what he did… he aligned the lay shaft pulley with the timing dot and the horizontal is at TDC. Yet, the vertical doesn't appear to be 90 degrees off, as he can't open the valves (which he should be able to do).
 

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Thats what he did… he aligned the lay shaft pulley with the timing dot and the horizontal is at TDC. Yet, the vertical doesn't appear to be 90 degrees off, as he can't open the valves (which he should be able to do).

Nope he has vertical at TDC. check 2:34
 

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Nope he has vertical at TDC. check 2:34
I think he was just talking about it, mentioning off the cuff that he could see TDC on the vertical. Few sentences later he said the timing marks on the lay shaft were aligned right now. There is no way he could have messed up the timing on the lay shaft.
 

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I think he was just talking about it, mentioning off the cuff that he could see TDC on the vertical. Few sentences later he said the timing marks on the lay shaft were aligned right now. There is no way he could have messed up the timing on the lay shaft.
At 3:31 he says horizontal is at BDC.
 

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Maybe he made his own marks on the layshaft pulley?
Maybe he did or maybe he didn't. But why would he?

For the 749/999 you can use the following.

Horizontal:
At horizontal TDC the pulleys T markings should point at 3 O'clock. The opening cam lobes are at approximately 2 and 10 o'clock, pointing inwards.

Vertical:
At vertical TDC the pulleys T marking should point at 12 O'clock. The opening cam lobes are at approximately 10 and 2 o'clock pointing away from the rocker arm.

If this doesn't solve the problem, he should check if the timing gear is aligned correctly. (if he "messed" with that)

Good luck.
 

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Discussion Starter #10 (Edited)
Here's the new video.



In the video, you'll hear me say that at one point both pistons are going down and then separate ( what I mean by separate is that one will make it's way up and the other go down).
Then I continue to move the crankshaft and the meet again, both going up and then separate ways again (meaning one will go down and the other go up).

I may have screwed up the crankshaft (when I had a rag to prevent any material from falling in). This was during the time I was moving the piston near or at TDC so I can pull it off the rod to clean the piston and replace the rings.

When I had the rag in the crank and was moving the rear wheel (didn't have the crank turning tool yet), the crankshaft gears pulled a little bit of the rag, I noticed it and moved the crank the other way to pull it (the rag) out completely.
This rag was in the horizontal bore of the crankcase. It never happened to the vertical ( I learned my lesson).
Perhaps, the piston rod's journal bit the rag but that wouldn't have made a significant change in the case I'm seeing now.

I kept thinking this over and over...could I have messed up the gears in the crankshaft? At first I thought, YES...I screwed it up. Then I consulted a buddy at work and we talked about it. There's no way that the rag bitten by the crankshaft gears would throw the balance off. It's a solid piece of metal. No way. Relieved, I proceeded to get everything back together again.

And now, it appears that I'm in the same position again thinking that I did screw up the crankshaft gears.
I'm starting to feel that I might have to open the whole entire motor. Spending probably $300 to $400 for a motor stand so I can take it apart. My wife you'll hear on the video is already ticked off. I've never ridden this bike for more than 1 year.
I'm thinking of counting my losses and selling her for a mere $3,000.
 

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Discussion Starter #11
Maybe he did or maybe he didn't. But why would he?

For the 749/999 you can use the following.

Horizontal:
At horizontal TDC the pulleys T markings should point at 3 O'clock. The opening cam lobes are at approximately 2 and 10 o'clock, pointing inwards.

Vertical:
At vertical TDC the pulleys T marking should point at 12 O'clock. The opening cam lobes are at approximately 10 and 2 o'clock pointing away from the rocker arm.

If this doesn't solve the problem, he should check if the timing gear is aligned correctly. (if he "messed" with that)

Good luck.
In regards to the vertical TDC. There's a yellow dot on the intake pulley. I was told to match that dot with a dot (made by the shop for easy reference in the future). When both those dots on the vertical, that's when ( I was told) to place the belts on. Once it's on, I move the crankshaft forward so the horizontal is back at TDC and I place the belts on the horizontal.

Are you saying that I'm supposed to place the horizontal at TDC...move it backwards 90 degrees so I can move the vertical's pulleys to an upside down T and then put the belts on the vertical?
 

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Discussion Starter #12 (Edited)
Thats what he did… he aligned the lay shaft pulley with the timing dot and the horizontal is at TDC. Yet, the vertical doesn't appear to be 90 degrees off, as he can't open the valves (which he should be able to do).
Correct.

Nope he has vertical at TDC. check 2:34

Dutch, @2:34 I had the horizontal at TDC. I hadn't rotated the vertical yet to TDC.

Thanks again btw everyone for helping out here. You have no idea how huge this helps me. If I don't have to pull apart the entire motor. OMG! That would save me lotsa time and more money. I'm gonna get rid of her as soon as this is all done.
 

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Discussion Starter #15 (Edited)
ok gents. I got it to work.
It appears for some forsaken reason, I was trying to remember the last time I did it.
Here's what I remember from the last time:
1) get the horizontal to TDC by using the marks on the layshift pulley, then
2) rotate the vertical piston to TDC and line up the vertical intake valve pulley to match the marks. The lil yellow dot on the intake pulley with a mark on the bottom side of that pulley that's tagged on the head (a mark made by the shop to reference future timing job)
3) place the timing belt on the vertical
4) rotate the horizontal back to TDC via layshaft pulley marks
5) move the horizontal cam pulleys to point at 3:00 o'clock
6) place the timing belt on the horizontal
7) turn the crank an even amount of times to make sure nothing jams into each other


With everyone's help, I realized that #2 is incorrect. Instead I should get #1 taken cared of and then align the marks on the vertical's intake pulley, pointing at 4:00 o'clock or 5:00 o'clock (while the horizontal is still at TDC via the layshaft markings). With the vertical done, ( I didn't need to rotate the layshaft) I just line up the horizontal pulleys to point at 3:00 o'clock and insert the belts.

Got both belts late last night and rotated the crank an even number of times to make sure nothing butted on each other and it was a success.

I was afraid, without putting the belts on, that I had a problem with the intake valve bumping against the piston when it was on TDC and of course I didn't want to put the belts on if that's the case. I thought back throughout this work (removing and reassembling the pistons / cylinder / heads) what I could have done wrong and I remembered the rag that was bit by the journal or the crankcase gears and I panicked. big time.

Thanks for impressing on me that I was wrong and that I should try again. Really appreciate that.

Now...onto the DYNO to break in the rings.
 

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With everyone's help, I realized that #2 is incorrect. Instead I should get #1 taken cared of and then align the marks on the vertical's intake pulley, pointing at 4:00 o'clock or 5:00 o'clock (while the horizontal is still at TDC via the layshaft markings). With the vertical done, ( I didn't need to rotate the layshaft) I just line up the horizontal pulleys to point at 3:00 o'clock and insert the belts.
Glad you worked it out.

For the 749/999 you can use the following.

Horizontal:
At horizontal TDC the pulleys T markings should point at 3 O'clock. The opening cam lobes are at approximately 2 and 10 o'clock, pointing inwards.

Vertical:
At vertical TDC the pulleys T marking should point at 12 O'clock. The opening cam lobes are at approximately 10 and 2 o'clock pointing away from the rocker arm.

If this doesn't solve the problem, he should check if the timing gear is aligned correctly. (if he "messed" with that)

Good luck.

That's when you turn the engine ccw 270 degrees, from horizontal TDC.

And please, next time read up on how the testa engine works. 'cause turning your engine cw 90 degrees.....and expecting it to be on vertical TDC...
You'll get TDC of the vertical cylinder that way, but it has the valves under tension as you are not at TDC of the compression stroke.

That being said;

Looking at your first video, it must have been quite frustrating.
Glad you have worked it out.

Cheers.
 
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