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Old 16-11-2020, 11:25 PM   #31
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I've not previously researched this subject, as I've never had to split my crankcases but, having a look at my reference books, I see that the workshop manual does actually explain how to carry out, what they call, the "Practical Method", as used by Andy in his video.

I'm sure you know this already, Richard, but, for the benefit of anyone else contemplating this job, here's the relevant extract from my Evo manual.





Note that, while the workshop manual specifies a preload of 0.3mm, another engine rebuild book I have suggests that a better figure is between 0.15mm and 0.20mm.

Out of interest, Richard, what preload have you used?
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Old 17-11-2020, 05:43 AM   #32
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I’ve reshimmed two so far, both with crank changes. Moto Rapido have always been a pleasingly quick source for replacement shims.
Don’t forget the gear shafts are also shimmed, although for free play rather than preload.
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Old 17-11-2020, 07:45 AM   #33
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I would try to get as close as possible to 0.2mm, any less and I feel when it gets hot the crank will expand less than the case and there is a chance that the bearing will be chattering.
0.3mm preload just seems too aggressive and that the bearing will wear when the engine is cold
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Old 17-11-2020, 09:18 AM   #34
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Buzzer I'm sure you know about this problem but for the benefit of other readers I had to have a crankcase split purely because the crankshaft oil gallery plug was backing out and would/might have eventually caused a catastrophic failure. It was loose in that it could be rotated by a screwdriver from the crankcase opening and you can't ignore doing something about it 2p worth of Loctite at the Ducati factory would have saved a lot of expense for future owners.

Here's an extract from "Ducati Up North" on the subject:

"The first problem is a design flaw in the pre-2000 model-year bikes that have an aluminum crankshaft oil gallery plug that can loosen and back-out. In doing so, the rotation of the crankshaft will machine the plug down until the plug eventually comes out and the engine experiences a catastrophic loss of oil pressure that destroys the main bearings (among other things.) The aluminum particles will end-up on the filter screen."
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Old 17-11-2020, 10:10 AM   #35
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Buzzer I'm sure you know about this problem but for the benefit of other readers I had to have a crankcase split purely because the crankshaft oil gallery plug was backing out and would/might have eventually caused a catastrophic failure.
Indeed, whilst in there definitely check this. Stake it/loctite it, whatever you can because you don't want it coming out.

Depending on your budget, might be worth getting the crank assembly balanced?
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Old 18-11-2020, 04:31 PM   #36
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the engine is all apart, and I am pleased with its condition... no bore wear, and everything look good. the main reason to take it apart is to bead blast the cases... which of course means a complete strip. I am glad I did it anyway as people have pointed out the crank plugs come loose which damages the cases. While this one was not loose, it was not tight either can came out with a gentle twist of the screw driver... disaster waiting to happen! its locktited in place now...




[img]I hate bashing bearings out,and where possible try to make a puller of some sort… in the case of the swinging arm bearings it’s easy, just a stepped bush (it does destroy the inner seal..) and out they come. the step needs to clear the circlip though… some of the engine bearings are more difficult as you can’t get to the back… for this I made an expandable stepped puller, that expands into the bearing as a bolt rides up an internal taper. with this they come out easy…[/img]





To get the bearings out I also heat the cases… I would like to use the oven as its a more even heat… but I can’t for two reasons.. the first is the cases are too big… and secondly she gets upset, particularly as its a new oven! So over the halogen heater it is… keeping an eye on the temperature… I also like to mark EVERYTHING, so it can go back where it came from, and in the same position. I am not keen on centre pops, instead I use a little diamond burr in the dremel… this will even mark bearings and means you can number stuff as well, and it does not cause stress raisers…



Of course parting the cases means the primary gear has to come off… and they are VERY tight… you can forget anything but a really robust puller. here is one I mad a few years ago. with this it came off easily.



The frame and wheels have gone to the powder coaters...

Last edited by buzzer; 18-11-2020 at 04:34 PM..
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Old 18-11-2020, 04:55 PM   #37
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Talking

If you keep going at this rate, the project is never going to last the winter!
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Old 18-11-2020, 04:59 PM   #38
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If you keep going at this rate, the project is never going to last the winter!



I said that to myself today i need to slow down... but thats hard
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Old 18-11-2020, 05:03 PM   #39
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I said that to myself today i need to slow down... but thats hard
I've yet to start anything to do with projects. Lockdown from Friday here, so may get ordering some belts and a service kit for the Monster. Then I've got a 1977 CZ Trail to start on. Need to completely strip that and do some frame alterations before it goes off to paint etc.
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Old 21-11-2020, 10:57 AM   #40
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Has anyone ever run an early monster without the vacuum fuel pump? Do you lose much tank capacity?
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Old 21-11-2020, 06:32 PM   #41
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here are the carbs, they are in remarkably good condition! I had some genuine new floats and needles so I used those in the build. I did bead blast the outsides, taking care to use silicone bungs in all the holes… they came out a treat!

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Old 24-11-2020, 05:23 PM   #42
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while the engine and frame are away I have turned my attention to overhauling the front forks… they were not leaking but I thought I would treat them to some new seals and dust covers…. looks like someone has recently changed just one side by the state of the oil...

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Old 24-11-2020, 06:02 PM   #43
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Has anyone ever run an early monster without the vacuum fuel pump? Do you lose much tank capacity?
Guess that’s a no then? I haven’t.
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Old 25-11-2020, 06:08 PM   #44
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the engine cases are back from the vapour blasters… what a superb job! attention to detail is what its all about and they came back prefect… I will definitly use this guy again… the finish is as good as I have ever seen… https://spvapourblasting.co.uk/ I know these cases are painted from original but the pain always flakes off, so I have decided to leave them bear, and use ACF 50 on them to keep them looking nice… this will probably be a low miles, fair weather bike for me…

the engine build begins… I got the cases nice and hot and pressed the bearings in, and then checked the crank and gearbox shafts end float as I wont be using a gasket as Ducati have now discontinued them and use Threebond in place … I had already ordered a few shims by measuring the old gasket (14 thou) and taking that off the shims that are in there… when the shims come in a few days I will build it properly…





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Old 28-11-2020, 05:43 PM   #45
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todays job has been cleaning out the oilways in the barrels after being vapour blasted... To do this properly and get every last bead of media out I removed and replaced the core plugs... they are cheap to buy. There was a surprising amount of crud behind them... Made a couple of stepped punches so I could drift them in nice and square.

Checked the bores for wear, there simply isn't any! Ground the valves in with some fine paste (how old is that tin of grinding paste ��) and checked I had a continuous seal with a sharpie pen. Gave the guides a quick clean with the burnishing hone which just removes carbon,

Finally, a good wash in petrol the tray and a check in the bottom for any blasting media. My mate who builds automatic gearboxes gave me the tip on the stainless steel trays... you really can see any debris in the bottom!

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