engine removal

[Fossilrider]

Well, a little more progress. I had such a time trying to re-install the valves/collets after removing them to replace the seals that I finally made a tool similar to the factory valve spring compressor. Also, as so often happens when one is dumb enough to have multiple projects going in the same area, I find myself with a few left-over parts. Does anyone know where these washers/shims might go? The one on the left is the size for a swing arm shim but I don't recall it coming from there. I have searched through the parts list book and found nothing with these dimensions. Thanks again for any help. FYI I didn't have the case apart so they don't go inside.

[George]

The one on the left 29.1 ID looks like a swingarm shim. No idea about the other two. Someone with more knowledge will be along.

[George]

The other two might fit on front wheel bearings

[Eldert]

the shim on the left is a shim for the lower bevel gear housing . it goes in between the housing and the beveltunnel
bottom piece .

Eldert

[Fossilrider]

Thanks guys. Now that it has been mentioned, seems like I do remember the one on the left coming from somewhere around the bevel shaft.? I will check that out since I have all that apart right now trying to double check the cam timing. I am having an interference problem between the piston and valves. Thought I had everything timed correctly but obviously not. After installing the head, I gently turned the engine over and the piston hit a valve, but not hard enough to damage anything.

[Bob_Matthews]

My valves interfered with the piston and my piston interfered with the head so I had to make a compression plate to get the correct squish and relieve the inlet cutaway in the piston.

[Fossilrider]

OK, not what I hoped to hear, that this might be a common problem. The dome on the Omega piston I am using is quite a bit higher than the stock, which I didn't really notice until I started to install it. So I contacted Lacey Ducati in UK and they said it should be a direct replacement for the stock piston, though it will probably raise the compression ratio maybe a half point, from 8.5 to about 9.0, which should be no issue. I assume the plate you made went between the case and the cylinder not between the cylinder and head? How thick did you end up making it? I'm not sure any NOS pistons are available, but if I could find one I might just get that and abandon this Omega item. I guess I need to do more research. Thanks for the reply.

[Bob_Matthews]

I believe the reason I needed a compression plate is that a previous owner had fitted a longer throw crankshaft from a 250 and then bored out the cylinder. The engine is a 200cc Elite, but with these mods it's now a 250cc and when I first stripped it the alarm bells rang as there were 3 base gaskets under the barrel.

I ended up making a 1.25mm thick aluminium compression plate (no gaskets) that goes under the barrel to get the squish within spec, I used soft solder in a clock arrangement on the piston to test the squish. The inlet valve cutaway in the piston was my doing as I fitted larger valves to the head than original.

How do you know it's the valves that are hitting the piston, rather than the piston hitting the head?

[ranton_rambler]

Do the test again but with the valves closed? You can remove the camshaft if the motor is at TDC and the valves will stay closed.

[blethermaskite]

your engine has I assume adjustable valve clearance rockers? if so the easy way to get a guide on piston to valve clearance is to back off the rocker adjusters to reduce the valve lift ........if its still hitting something (and your valve timing is correct?) the piston to head clearance is off.
Cheers,
George