Primary gear alignment.

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andybaggies
Cucciolo - the Lil Pup
Posts: 24
Joined: Thu Nov 01, 2018 12:52 pm

Primary gear alignment.

Post by andybaggies » Sat Mar 16, 2019 1:09 pm

As per the title is there a recommended alignment of the primary gears?

By alignment I mean should the primary gear be sitting bang in the middle of the clutch basket gear, or is it allowed to be a little further back as it presently is on mine? i.e

Oh r's I can't even draw a basic diagram in a post, ahem, so give me a moment or two....

Cheers,

Andy B

wdietz186
Cagiva Alazzura
Posts: 703
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Re: Primary gear alignment.

Post by wdietz186 » Tue Mar 19, 2019 7:27 am

The gears should be pretty well lined up, the engine gear is fixed due to being mounted on a taper. There should be a thickish washer behind the clutch basket, between the case bearing and the bearings in the basket. You might have an issue with the bearings in the basket. There should be a spacer between them and I think there is a circlip retaining them. If I remember correctly there was a production change in the bearings noted in the parts book. It has been a very long time since I looked at my bike but I think mine were mis aligned by a few mm's but there was no unusual noise or wear evident.

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Craig in France
Cagiva Gran Canyon
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Joined: Tue Mar 23, 2004 3:58 pm
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Re: Primary gear alignment.

Post by Craig in France » Wed Mar 20, 2019 1:01 am

When I noticed something similar on my 450, Nigel Lacey told me to stop worrying ... ;)
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andybaggies
Cucciolo - the Lil Pup
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Joined: Thu Nov 01, 2018 12:52 pm

Re: Primary gear alignment.

Post by andybaggies » Wed Mar 20, 2019 11:40 am

It has been a very long time since I looked at my bike but I think mine were mis aligned by a few mm's but there was no unusual noise or wear evident
Just popped out and measured and the clutch gear is ~1.5mm proud of the primary gear. And from what I can remember there was no unusual noises when it was last running.

I'm putting in a sachse ignition system & as I'm in there I might as well whip the basket out just to check nothing is awry. A quick check of the gear selector spring thingumybob wouldn't be out of order either.

Which of course makes me think I should really do a proper job & check the starter sprag bearing as well.... Even though it feels ok.
Nigel Lacey told me to stop worrying ...
We can't be doing that with a Ducati can we :?

Many thanks guys :)

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81mhr900ss
Mach 3
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Re: Primary gear alignment.

Post by 81mhr900ss » Fri Mar 22, 2019 7:59 pm

I just looked at mine, and estimate the clutch gear to be the same as andybaggies' about 1.5mm proud of the primary gear.

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Craig in France
Cagiva Gran Canyon
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Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Primary gear alignment.

Post by Craig in France » Sat Mar 23, 2019 12:55 am

Andy, my advice would be to DEFINITELY change the gear return spring, regardless of what it looks like. Just make sure you get one from a reliable supplier (preferably a better supplier than the one Ducati used ... :-D :doh: )

And me, I'd change the sprag as well ;)

andybaggies
Cucciolo - the Lil Pup
Posts: 24
Joined: Thu Nov 01, 2018 12:52 pm

Re: Primary gear alignment.

Post by andybaggies » Mon Mar 25, 2019 11:32 am

I just looked at mine, and estimate the clutch gear to be the same as andybaggies' about 1.5mm proud of the primary gear.
Thanks for the confirmation. Taking the clutch drum off at the weekend showed the 4.8mm spacer was fitted but no extra shims. All looks clean so I'm happy with that :)
my advice would be to DEFINITELY change the gear return spring
I think i'll take your advice on this - I'll see if Lacey have one & if not Ducati Classics in Holland or Mdina should sort me out.
And me, I'd change the sprag as well
Well when I was assembling & farting about with a puller adaptor I had made up years ago I remembered that this was the last job I did on the old girl - replacing the sprag. But, for a variety of reasons, it was never actual used in anger. So as I don't like removing the flywheel, too much biffing and force for me :~, I'm gonna leave it as is :oops:

But even at hand speed it does catch & release as it should and there should be no more kick backs with the new all singing dancing ignition system - yeah, I know, I know.

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