Connecting Paso Tachometer on a M900 monster engine

discussions specific to the 750 Paso

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lceriani
Posts: 163
Joined: Mon Jul 19, 2004 12:00 am
model: 750 Paso
year: 1988
Location: Saronno (Varese), Italy

Connecting Paso Tachometer on a M900 monster engine

Post by lceriani »

I would like to install the mechaninc Paso tachometer on my M900 engine and I would appreciate some help...

As you see from the picture below, Paso mounts a mechanic tachometer connected to the head timing system: the "GEAR WORM" assembly (#13 + 15/16/17/18) transmits the movement to the cable.
Image

In the first 1993/1995 M900 engines there was not a tachometer, but still Ducati keeped part of the assembly, replacing the gear worm (ex #13) with a spacer (#4) and a plug (#16):
Image
However In next years Ducati mounted electrical tachometers instead of mechanical ones and finally covered the "hole".

My idea is to recover the mechanicals parts #13/15/16/17/18 from a Paso and try to connect them to the engine. So here it comes my doubt: do I need to disassemble all the head to access those parts? Or I just need to disassemble the pulley timing assembly?

LC
Martian

Post by Martian »

Luca,

You certainly like to take your 'modifications' seriously!

I am currently taking a lunch break, (whilst at work), and browsing over the two engine diagrams that you have submitted and, from what I can see, (but not from what I know ), it appears that the main cam shaft in question, (#21), appears to enter from the rear of the cylinder and passes through the head, (towards the front), where the worm gear is attached, (is that a woodruf key that I see)?

There appears to be bearing cages at the front and the rear and this would suggest that the entire assembly could be removed, after the various gears and locking nut, (#6, #8 & #9), have also been removed), but the cam follower, (#13), would have to be pulled clear to facillitate this and this may require a strip down of the head assembly!

Would it not be less trouble to utilise an electronic tacho, (taking it's feed from one of the two sensors on the timing plate), and then trying to find a suitable electronic tacho that could, itself, be modded to fit into the existing clock assembly, (utilising the original needle)?

There will, of course, be an issue with getting the replacement tacho reading to line up with the original, (mechanical), tacho's scale!

I will know more about, both, the engine details and that of the clocks, once I have got to those respective parts during my, continued, refurb project but I have a half marathon in Kent to look forward to, (this weekend), so I will not be getting my hands dirty over the next few days I'm afraid!

Of course I may be incorrect in my initial assumptions and there may be somebody else 'out there' who has overcome a similar problem . . . . . .
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paso750
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Post by paso750 »

I`m sure you can remove 13-18 (the drive) without disassembling the head. To remove the speedo "snail drive" from the cam I don`t think the cam needs to be removed. As you see on the front side there`s a ball bearing pressed in the cyl. head. So I think it should be enough to remove the cambelt pulley to pull off parts 7-12.
I can check this at home as I have Paso and newer SS/Monster heads laying on my bench.

Gerhard
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jcslocum
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Post by jcslocum »

Looks like it can be done with out removal of the cam. I hope that the key slot is still machined into the cam shaft.

Good luck!
ducster

Look at...

Post by ducster »

... Position 13 at Paso Head and verify with position 4 at M900 Head! It's the Driver @ Paso Tachymetercable, @ Monster there's only a Distance Ring placed. You have to change it, too!

Good Luck,
Olaf
lceriani
Posts: 163
Joined: Mon Jul 19, 2004 12:00 am
model: 750 Paso
year: 1988
Location: Saronno (Varese), Italy

Post by lceriani »

Thanks Olaf, I have to replace M900 part #4 with Paso part #13, but do I need to disassemble all the head to access those parts or just the pulley timing assembly?

LC
lceriani
Posts: 163
Joined: Mon Jul 19, 2004 12:00 am
model: 750 Paso
year: 1988
Location: Saronno (Varese), Italy

Post by lceriani »

Gerhard,
I haven't applied this mod yet, but I am going to work on it.
So did you check with your head if the cam need to be removed?
Thanks,

LC
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paso750
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Post by paso750 »

Luca,

sorry, sorry, sorry. I`m checking the board very rarely lately. My Paso projects are going in a different direction :)

You don`t have to remove the cylinder heads. Remove belts, cam belt pulleys, speedo drive and then the cam. But beware that you use some clips to hold the valves in position. As every part is "insode" the cyl head there`s no reason why you have to remove it unless a valves drops in.
I don`t see any problems here.
Check also the Haynes manual download.

Gerhard
lceriani
Posts: 163
Joined: Mon Jul 19, 2004 12:00 am
model: 750 Paso
year: 1988
Location: Saronno (Varese), Italy

Post by lceriani »

Thanks, Gerhard!
Last sunday I had my last ride for this season (toooooo much cold! Today I woke up with snow...) so probably I'll start next weekend and your infos are right in time.

Finally I bought this haynes manual:

Image

Probably it is the one you are referring about... isn't it?
Bye!

LC
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