Remove the bevelshaft without dismounting the crankshaft?

[LaceyDucati]

Rocla

My opinion is gear noise and I would investigate and correct. My opinion for what it's worth.

Nigel

[Rocla]

Thanks for your replies!
I will check with blue ink. In fact, I tried to use color last week before remounting the engine but it was not conclusive, because of the ink, too clear. I will check, I am not totally comfortable with this noise, even if your Mach did that, and even if a Mark on youtube has exactly the same noise. I think my setup is acceptable but maybe not optimum (for the bottom bevelgear). Anyway, before dismounting, I will go to the oldtimer Ducati specialist in order to ask him about this noise. I hope he will accept to give his opinion for free, he is usually not very cooperative

[LaceyDucati]

Rocla

This is what I mean by engineers blue, not to be confused with marking out blue etc. It is non drying and very messy if you are not careful!

http://www.ebay.co.uk/itm/Stuart-Engine ... 0405691880

A little goes a long way and you only need the very smallest amount. This is a life times supply for many engineers!

You may of course know this.

Nigel

[machten]

My opinion is gear noise and I would investigate and correct. My opinion for what it's worth.

Nigel

Yeah, I'd agree there is a gear whine there based on what I can hear. Just my opinion, too (but to be clear, my opinion is based on about 1/1,000 th of Nigel's experience )

Kev

[Rocla]

Hello everybody,

I am convinced. I've dismounted the bevelgears. It seems OK on the camshaft bevel but too tight on the bevel shaft one. It is due to the fact I had changed the circlips (the previous one were dented) without rechecking the setup. It modified the position of the bevelshaft pinion. And I confirm, there is a little resistance when I rotate the shaft. My fault was not to setup again after removing the circlips...

[Rocla]

Hi,

I find out the reason why the noise: the bottom bevelgear bearings were not tight enough (with a big play and consequently vibrations), and the bevelgear itself was too tight, with no play. Here below the new relative position of the 2 pinions:

Dsc04997.jpg

And here below the test with the ink:

Dsc05003.jpg

For me, given that there is a very little play but it rotates freely, and given that the contact areas are relatively long and wide on each teeth, this setup is probably relatively correct. What is your opinion?

[LaceyDucati]

Rocla

The set up shown indicates the crank gear is correct as the contact patch is central side to side. However the contact patch is low in the tooth, this would indicate the vertical shaft may need to move up slightly. This would increase play slightly, maybe the gear mesh is slightly too tight, only experimentation will tell. The patch should be ideally central in the tooth, much as yours is but slightly further out. However this is one of those difficult to judge things by description and photo's, and what you have there maybe the best compomise especially with matching odd gears.

Nigel

[Rocla]

Thanks Nigel.

It was a liitle bit my feeling and I've tried to put the bevelshaft a little bit higher but I don't have 0,05mm shimms, only 0,1mm and it was too much (the play became too big). It is not simple... I think it is a good compromize.

It is not criket. I saw for example that if you don't check the play without tighten all the bold and nuts between the headcylinder and the bottom shaft, the play is not the defintive one. Especially if the bottom bearings are not load! I think it was the problem on my first setup (play between circlip and bearings, and not play enough once everything was tight), and the reason why the noise...

[Rocla]

Hello everybody,

Here is the new sound of my engine, with a better setup :

http://www.youtube.com/watch?v=HfV1_c15 ... e=youtu.be

The hiss vanished, and the engine is more reactive at high speed...

Many thanks for your pieces of advise !