Slow Monster rebuild

[Luddite]

Here are the accompanying notes...

[utopia]

Have you come across the internet writings of Brad the Bike Boy ?
You may find some useful data on valve timings there.

And while I'm posting
In the quote below, I presume you meant the little hand of the clock, not the big one.
Just so as you know I was paying attention.

Originally Posted by 350TSS

Studying pictures of the original assembly the vertical cylinder inner cam belt timing mark is at about 09.30 on the big hand of an imaginary clock if the clock face is aligned between the centres of the upper and lower pulleys. This is where I will set my newly marked adjustable pulley as I put the belt on.

[Luddite]

Originally Posted by utopia

Have you come across the internet writings of Brad the Bike Boy ?
You may find some useful data on valve timings there.

If I remember correctly, that's where my table came from. He is VERY knowledgeable about Ducatis...

[350TSS]

Thanks guys,
I did use the table you have posted from Brad the Bike Boy, particularly, the row identified as "900 correct 0.2mm" where Inlet Opens is 43 and Inlet Closes is 85.
Assuming he in all cases is referring to before top dead centre (BTDC) then in my world of a 720 degree 4 stroke cycle TDC occurs at 0 degrees, 360 degrees and 720 degrees.
so IO at 360 - 42 = 317 degrees and IC occurs at 720 - 85 = 635 degrees.
(elsewhere in that row he defines Inlet duration as 308 degrees but 317 + 308 = 625 degrees, but what does 10 degrees matter when the Ducati tolerance is +/- 5 degrees?)
Assuming that the ramp up and ramp down profiles are the same then his peak valve lift should occur at the mid-point between IO and IC i.e. 635 - 317 = 318 divided by 2 = 159 + IO degrees 317 = 476 degrees.
My vertical cylinder results average out at 444 degrees so I am 32 degrees advanced on current settings.
There are 18 teeth on the cam belt pulley so each tooth represents 20 degrees but the cam belt pulley runs at half engine speed so 1 tooth out represents 40 degrees of engine rotation.
On my clock face analogy, the difference between 09.00 and 0930 for the little hand would represent
15 degrees on the cam pulley or 30 degrees of crankshaft rotation. (Utopia it has to be the little hand as the big hand would be at 06.00).
So today I will be re-measuring the horizontal cylinder and taking the cambelt off and re-setting to 09.00.
Fine adjustment using the mechanism within the alluminium pulley will follow - it could be a long day.

[350TSS]

My long day turned into quite a short one, after about 2 hours of messing about trying to measure the horizontal cylinder valve lift it was obvious that my spurious results were being caused by the DTI not following the movement of the rocker arm. Lazy spring, a slightly bent actuating spindle or possibly something internal to the mechanism catching, whatever, I decided a new one was required.
I had to wait two days and then, of course, it would not work with my Mk2 holding bracket so a new one was fabricated.

Then I got a cold and stayed indoors for the next day.
Back on it again next week and I think I have a better way of setting the valve timing than relying on guessing the position of non-existent marks on the inner cam belt cover. Namely, first setting the adjustable pulleys in the middle of their adjustment, putting the crankshaft on the right stroke for the opening of the inlet valve, then positioning the engine at the point where the inlet cam is due to open and rotating the camshaft to the point where the DTI registers the first movement then aligning the camshaft pulley keyway with the belt on it and pushing the belt and pulley on.
Should be a breeze with the possible exception that foolishly I loctited everything on first assembly in the belief that I would never be more than a few degrees out (it is obvious that I know enough to be dangerous but nowhere near enough to be good) and if I was it could be easily accommodated by the adjustable pulley

[350TSS]

Finally got my cam timing sorted this afternoon - I managed to get the vertical and horizontal cylinders within a degree of each other and each within a degree of the cam opening times specified in the table posted by Luddite #1110 on the previous page - well pleased
Just got to find the flywheel and the clutch centre now and the engine can be buttoned up.

[350TSS]

I am posting this whilst trying to warm up, having been in the garage all morning.
The first job was to find the flywheel and the clutch centre, tick for the first but the second still AWOL.
Even though kept in a plastic box and sprayed with WD40 some light corrosion had to be dealt with first, then re-assembling the sprag clutch and starter gear.
This took about half an hour to line up before it eventually slid home. It seems to work OK and whilst you can see it is not new it still has good service life remaining.
I located the flywheel and pushed it home and then realised with the engine out there was no means of stopping the engine from turning. Unfortunately, I had already applied the loctite to the crankshaft alternator rotor nut and I did not want it to go off at about 25Nm.
I noticed that there were 4 holes (7mm) drilled in the outer face of the flywheel and decided to tap them out 8mm. I quickly knocked up this holding device from a bit of scrap angle iron and bolted it to the flywheel.

I worried a bit about whether changing 4 x 7mm holes to 4 x 8mm tapped holes might alter the balance of the flywheel - but it is done now.
A good half an hour was spent picking thread swarf off the rotor magnets.

Next problem I have 3 torque wrenches, my bestest digital one 3/8 drive (red handle) capacity 135Nm, my ancient Clarke 1/2 drive, spring-loaded (probably miles out of calibration), capacity 150 Nm and a quarter drive one. None will go to the 157Nm required (Haynes manual). I did it up to 150Nm and then put a breaker bar on it for another tweak. I do not think it will be going anywhere.

[Luddite]

Necessity really is the mother of invention! That flywheel locker is very ingenious.

I shouldn't fret too much about flywheel balance; when I changed my flywheel for a heavier one from a Hypermotard, I noticed it had an additional hole, which is not present on the Evo's. (I think it contains a dowel or pin on the Hypermotard).


Hypermotard flywheel on right with extra hole

Like you, I wondered about balance and asked Wilf at Moto Rapido for his opinion. He said it'd make no appreciable difference and to ignore it - so I did.

I've been running it for over three years now with no problems so I'm sure you'll be fine.

[350TSS]

This afternoon I replaced the crankshaft bearing in the alternator case, fitted a new gearchange oil seal and the glass window for the timing pointer, bolted in the alternator stator, cleaned the gasket faces and bolted it on.
This case had to be welded following the classic mistake of trying to take it off without removing the screw adjacent to the clutch slave position. This is the first time it has been put back on since I got it first welded then powder coated. The rearmost screw was slightly misaligned and had to have a tap run through it and the case itself creaked a bit when I torqued it up so obviously the welding has caused some distortion. Worst case will be the case cracking at a later date because it is being forced into a position it is not comfortable with. More likely the case will not hold oil because the gasket face is not perfect, I did my best to get the mating surface flat with a sheet of 600 wet and dry on a granite worktop before I sent it to powder coating. We shall see.

[slob]

I went the opposite way for track use, losing 2/3 if the DS’s original 1800g flywheel. Tickover’s not great but it spins up ridiculously quickly and engine braking feels like Brembos. As Vince says a couple of grammes won’t be noticeable and since your four holes are evenly spread, balance should be perfectly maintained anyway.

[Luddite]

Originally Posted by 350TSS

More likely the case will not hold oil because the gasket face is not perfect, I did my best to get the mating surface flat with a sheet of 600 wet and dry on a granite worktop before I sent it to powder coating. We shall see.

That really is a lovely looking engine.

Have you used traditional fibre gaskets on the crankcase? If so, and it does end up leaking, maybe Threebond 1215, as used on the later models, might be flexible enough to achieve a good seal.

[350TSS]

Moto Rapido does not stock the traditional gaskets anymore and offered 3 Bond as the alternative which is what I am using. As a bit of a Luddite myself I must say I prefer proper gaskets without goo as they tend to come off easier and if compromised and not re-usable it is a lot easier to clean the faces

[utopia]

Regarding the alternator rotor nut ....
On the one hand, I would have thought that 150Nm is close enough to the 157Nm spec as to make no appreciable difference, so you should be fine there. Indeed, my factory manual allows a +/- tolerance of 5%.
On the other, I'm concerned about the length of time that it must have taken to tap out the holes in the flywheel and to make the holding tool. I would have thought that this would have been more than long enough for the previously applied loctite to have at least partially cured and therefore its locking function after subsequent tightening to spec torque would likely have been compromised.
It may well have compromised the levels of applied torque/clamping force too, for that matter.
As this nut is apparently known to come undone in isolated cases, I would be nervous about trusting it in its current condition.
Not that I have any hands-on experience of this area myself you understand .. I'm just speaking theoretically.
Why did you not just clean off the loctite and re-apply after you'd tapped the holes and made the tool ?

While I'm on the subject, I notice that my factory workshop manual (admittedly for a later, yr2001 M750) states that a new nut should always be used.
The Haynes manual makes no mention of this that I can see.
Personally, I would replace the Belleville washer too.

[Darren69]

Originally Posted by utopia

Regarding the alternator rotor nut ....
On the one hand, I would have thought that 150Nm is close enough to the 157Nm spec as to make no appreciable difference, so you should be fine there. Indeed, my factory manual allows a +/- tolerance of 5%.
On the other, I'm concerned about the length of time that it must have taken to tap out the holes in the flywheel and to make the holding tool. I would have thought that this would have been more than long enough for the previously applied loctite to have at least partially cured and therefore its locking function after subsequent tightening to spec torque would likely have been compromised.
It may well have compromised the levels of applied torque/clamping force too, for that matter.
As this nut is apparently known to come undone in isolated cases, I would be nervous about trusting it in its current condition.
Not that I have any hands-on experience of this area myself you understand .. I'm just speaking theoretically.
Why did you not just clean off the loctite and re-apply after you'd tapped the holes and made the tool ?

While I'm on the subject, I notice that my factory workshop manual (admittedly for a later, yr2001 M750) states that a new nut should always be used.
The Haynes manual makes no mention of this that I can see.
Personally, I would replace the Belleville washer too.

I was gonna mention this but you beat me to it Geoff. It was fairly common for that alternator nut to come loose as happened on my 748 and I beleive it is now included in the service intervals, but wasn't previously. I can't remember exactly the details but there may have been a part change to the washer itself.

[350TSS]

Not much gets past you guys.
Confession, the holding tool was already in stock from some long-forgotten project. When I knew I had to find a means of holding the crankshaft I looked in my assorted puller/oddball special tools box and buried deep within was the tool above.
The time the loctite was on the crankshaft was the time it took to tap two holes and torque it up, maybe 20 minutes tops. To limit the effect on flywheel balance, I tapped the other two holes afterwards.