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I'm trying to figure out if I'm doing anything wrong with timing this 450. See picture below I have aligned the dot on the crank with the idler that drives the oil pump (which you can't see in the picture) but I have a couple of questions:

1. Although the way I have aligned the bevels will result in their corresponding dots meshing correctly, the piston is at TDC when this picture was taken and they are not completely meshed - is that correct?

2. The book that I'm using says that on 450 models, the scribed line on the timing idler gear should be used - I can't see any such scribed line???? What am I missing?

Thanks in advance.

Ian

Hi Ian

there are more then 1 type small bevel gears . the dot should be at the 11 o clock position

some gears have the dot at the keyway so the 12 o clock position

Eldert

On my 200 there are two timing dots on the lower gear. I don't know if the 450 is that way.

Hi Ian,

What position is the lower bevel vertical shaft in? It has to match up with the corresponding half-shaft of the upper bevels, and that position is set by the camshaft position - ie the cam lobes must be at 4 and 8 o'clock and the slot in the end of the cam must be vertical when the piston is at TDC; if you have to rotate the cam to get the shafts to match up then something is wrong.


Cheers,

Colin

Thanks Eldert. So I THINK what you are saying is that what have looks right - with the piston at TDC the dots on the small bevel gears will be at 11 o’clock?

Ian

Eldert wrote:Hi Ian

there are more then 1 type small bevel gears . the dot should be at the 11 o clock position

some gears have the dot at the keyway so the 12 o clock position

Eldertbottom bevelgears.jpg

The head is off at the moment Colin but yes, I am setting the cam lobes at 4 and 8 for reassembly.

Ian

Duccout wrote:Hi Ian,

What position is the lower bevel vertical shaft in? It has to match up with the corresponding half-shaft of the upper bevels, and that position is set by the camshaft position - ie the cam lobes must be at 4 and 8 o'clock and the slot in the end of the cam must be vertical when the piston is at TDC; if you have to rotate the cam to get the shafts to match up then something is wrong.


Cheers,

Colin

Hi Ian,

this is what I've found in my 450 motor - the scribed line is clearly visible in the picture.

Cheers

Wolf

Thanks Wolf. Strangely my timing idler definitely doesn’t have that scribed one but it’s entirely possible it was swapped out at some point over the years. In many ways it doesn’t matter too much - I have an Electrex ignition system from Lacey Ducati on this machine and I can set the timing at 28 degrees BTDC with the idler in either position.

Ian