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My bearings have play, My manual shows 2 bearings same type, are they anything special? any tricks to get them out without the factory tool?Any tricks to seperate the cases that dont involve screwdrivers between cases or hammers to the crank ends!!

Just two bearings and a spacer inside a housing - nothing special, just replace the bearings facing the same direction as they came out. If you're just replacing the lower bevel bearings you don't have to split the cases.

To remove the lower bevel housing without the special tool remove the aluminum cover that holds the housing in the case. Tap the underside of the lower bevel gear to drive the housing (with gear installed) upward until the gear touches the case. Then, using two blocks of wood to protect the case, use two screw drivers to carefully pry the housing out without damaging it. Depending on how tight a fit it is, you may need a little heat. You may need to reshim the bevel gears after replacing the bearings.

When I split my cases I tapped on the mainshaft and they came apart nicely.

Thanks KMEV, the crank is comming out to be re-_aligned, nice of you to take your motor appart just to show me the way!!

By: 'Bevel bob'...
" My manual shows 2 bearings same type, are they anything special? "

____ They both have normal/cheap (single-row) ball-bearing sets, within 15x35x11mm L-races.
I was once advised (back in the '70s), that it's better to replace them, (at least the lower of the two), with the costlier/superior dual-row 'self-aligning' bearing, that's same as used stock on the upper tower-shaft (just under it's bevel-gear head). _ So I tried that, but without any notable effect.


" Any tricks to seperate the cases that dont involve screwdrivers between cases or hammers to the crank ends!! "

_____ RIGHT! - As I really hate to learn of anybody doing such hasty case-splitting work !
I've come-up with two different ways to split the cases without the factory-tools for that job!
However, nobody ever really wants to bother to make the items needed to do the job my way, in order to only split just their one & only case-set.
___ I first came-up with a good method for the job, from the right-side (with both right-side case-covers and sprocket & crankshaft bevel-gear removed). ...
I cut a block of 2-by-10 wood to be slightly longer than the motor-case. _ Then drilled 3/8" holes to line-up with the four 8mm motor-mount holes. _ Then after setting-up four (near foot long) 5/16" threaded-rods through the motor-mount holes & those of the wood-board, (for helping to keep the board aligned with the right-side of the crankcase), marked locations (for several holes to be made) which line-up with at least three of the 6mm threaded-holes in the motor-case, (preferring to choose those which don't have alignment-dowels, if ya don't have any long 6mm bolts), and also for the two holes to line-up with the crankshaft & lay-shaft.
Then drilled all the holes... five, 5/16" holes (for easy fitting of the 6mm bolts), and two additional 3/8" holes, one directly aligned with the tip-end of the crankshaft, and the other directly aligned with the sprocket/lay-shaft.
__ Next, with the wood-board bolted in place to the side of the motor-case, (use at least three 6mm bolts, if not 5), I then use two -(1 short & 1 long) 7/16th" lag-bolts -(with their pointed-tips ground-down, leaving one with 3-inches of thread-travel & the other with 6-inches), for the crankshaft & lay-shaft (respectively), screwing them through the wood-piece until up against their respective shafts. _ Ya ought to help protect the shaft-ends with a thick spacer-washer (or a nut), and then with the flattened tips of both bolts turned equally snugged up-against their respective shaft-ends (through the added spacer pieces), slowly tighten both bolts at once, (or each one separately, no more than a quarter-turn at a time), until the cases split & pull the right-side main-case (hopefully along with it's main-bearing), off & away from it's normal-fit on the crankshaft.
__ If you prefer to use 2-by-4 wood, I can tell you how to make-do with 3 pieces of that size. And if you wish advice on how to properly locate the exact positions to drill your holes through your piece of wood, then please ask for further advice.
___ For splitting from the left-side, I made my own splitting-tool using a crankshaft/primary-cover plug... I drilled through the plug's 14mm hex-depression with a 5/16" drill-bit, and then tapped it with a course 3/8" tap.
__ After the clutch and alt.rotor, etc., has been removed, ya reinstall the primary-cover (with at least 3 of it's screws!), then with it's plug-cap removed and the modified plug-cap installed in place,, ya then screw a 3/8th" course-thread bolt into & through it until turned up-against the tip-end of the crankshaft, then continue turning it slowly until the crankcases split. _ Whacking the back-end of the cases with a rubber-mallet (at the same time), can help break a stubborn seal.
__ This modified-plug/cap-tool can also be used to pull the primary-cover (just itself), by having all of it's screws removed, while the crankcases are still fastened together !
___ With either of these two methods, of course be sure that you've first removed all the screws & bolts which hold the main/crankcase-halves together !
__ Let me know which of these two ideas of mine you choose to go with, as I'll then give some added details for that chosen method.
___ However if ya don't really care about doing it using either of my two different methods, (since ya only have your one single case splitting-job to accomplish), then I hope you'll be extra careful with using the far more common 'hammer_&_screwdriver method' ! _ And if so, may good-luck then be with ya!


Hopeful-Cheers,
DCT-Bob

Thanks Bob, The wife suggested I use two small shaped charges of C3 placed either side of the crank, I think she's a bit jealous .

Bearing bush is out, bearing balls now distributed throughout engine and garage corners.Now looking for method to remove outer bearing tracks from bush!! The replacements are polymide caged,replacing metal caged, about 25 quids each,not sure that polymide good at aircool motor temps.

The lower bevel bearings are angular contact type. Ducati used these to handle the axial loads. The Ducati (Clymer) manual has a good photo of the bearings and spacer showing the angular type races. It's strange they deemed it necessary to use angular bearings here because the mains on singles are just standard bearings. the helical primary gear surely imposes axial loads on the crank mains. The twins do use angular for both applications. Any end play with angular bearings can be a very bad thing. For these lower bevel bearings, a shim is placed under the circlip, and it should fit snugly to put a little preload on the bearing pair. Make sure you get the bearings in the right direction! If you are replacing the bearings in the cases, and heating them in an oven, you will find the lower bearing assembly will slip right out at about 250F. The case bearings are fit tighter, and will require a little more heat to drop out.

Scott

I can see why the top bevel bearing needs to be angular type, but there seems no logic in the bottom pair to be angular,I'll fit what Mr Lacey sends me.I can also see why crank float needs to be nil,although the manual says 20 thou!! Clymer is full of daft stuff.

" I can see why the top bevel bearing needs to be angular type, but there seems no logic in the bottom pair to be angular, "

____ I'm not an expert on bearings in general but, I can grasp the concept that there's likely some vertical pressure (sourced from the meshing helical-type teeth of the bevel-gears), which standard ball-bearing type bearings are not specifically made to cope with very well. _ Cuz while such standard bearings have race-slots with plenty of load-bearing surface-area to properly deal with rotating/radial-loads, they unfortunately don't also provide much surface-area to handle any vertical/axial-loads. _ So for this case, Ducati rightfully used a bearing-type which has a L-shaped (as opposed to C-shaped) race-slot, to provide not only a wall but also a floor (or, a ceiling), so that the race-slot provides more useful load-bearing surface-area where it's more apt to be needed !
So now ya should see that at least one of that type of "angular" bearing is needed to properly cope with any possible vertical-loading !
__ It's my opinion that Ducati's chosen bearing-type can handle far more vertical-pressure than it's likely to be subjected to however. _ So I wouldn't be too afraid to try other suitable types of bearings (which aren't so difficult to work with).
So if it were my own project,, I'd use the same dual-row ball-bearing that's stock on the upper-bevelshaft, in place of the lower stock-bearing (for the lower-bevelshaft), and a standard-type ball-bearing in place of the upper stock-bearing (for the lower-bevelshaft). _ As the vertical-load handling of those two types of bearings should still exceed any vertical-pressures that they must normally handle (at the positions given for each), so as to hold-up for similar life-spans.
__ I do agree that the TYPE of bearing that's used as the UPPER bearing (for the lower-bevelshaft), is not really required and that it SEEMS as if there's no logic for that type of bearing to be installed in that particular location. _ So it appears that the only likely reason for that stock-type of bearing to also be installed at the upper-position as well, is merely for the purpose of just keeping the whole-assembly as one complete/workable-unit. _ Thus if the lower stock-bearing was not the type of bearing which it is, then there would be no useful-reason for that exact-same type of bearing to be (flipped-over upside-down) at the upper/opposite-end (of the lower-bevelshaft) ! _ Also, it was likely cheaper to just double the number of same-type bearings ordered, (for cheaper mass-production).


" I can also see why crank float needs to be nil, although the manual says 20 thou!! "

____ That's a half of a mm ! _ So are you sure that the Clymer-manual didn't actually mean '.20mm' ?


DUKE-Cheers,
-Bob

I lost confidence in Clymer when I read tighten the clutch nut to 700-850 foot -Ibs,thats 100Ibs using a 7foot bar!!,somehow I don't think so.Also tappet clearances for Mach 1 inlet 9.8 thou ex 16 thou?. I'm also having to question everything I find in this motor, certainly can't put bearings "back the same way they came out"! I need to really understand.The bottom bevel was shimmed far to tight which is likely why the bearings were worn out and nut loose.