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Re: 750 Sport restoration project

Posted: Sat Jan 13, 2018 11:26 am
by Andrew2
One step closer to finally getting her on the road. My vintage club examiner passed her for registration so she should be on the road in the next couple of weeks. Can't wait.

Cheers
Andrew

Re: 750 Sport restoration project

Posted: Sun Jan 14, 2018 11:06 am
by paso750
That's good to hear! :thumbup:
Pity about the tank tho. If that was caused by underpressure I wonder if one could go the opposite way to fix it. Pressurize it and warm up the dents. Maybe they would pop out. Getting pressure inside the tank would be the difficult part.
If you changed the belts back in 2013 they are due again ;)

G.

Re: 750 Sport restoration project

Posted: Mon Jan 15, 2018 10:43 am
by Andrew2
I tried pressurizing the tank with compressed air but wasn't sure how far to go and ended up chickening out LOL. I'm going to see a dent removal fella that's in my vintage club and see what he says. I'm amazed at how thin the metal is on the tank to be honest.

Re: 750 Sport restoration project

Posted: Sat Feb 03, 2018 5:53 am
by Andrew2
She's registered at last. New Historic plates and a new rear tyre. Unfortunately the front is on back order.
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I still have a couple of things to do before I get to ride her like putting on a new chain and sorting out the clutch.
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Is this the bolt that holds the front sprocket on?.
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Next job to is to figure out why there's no pressure at the clutch lever. I'll pull the master off first and check for wear. If that looks ok then I'll have to take the clutch cover off and check out the slave. I think there's something in the FAQ about replacement slave rubbers etc. Maybe off a Monster?.
There's other little things like connecting up the indicators etc but they're only minor....I hope lol. Oh,and a new battery.

Cheers
Andrew

Re: 750 Sport restoration project

Posted: Tue Feb 06, 2018 10:15 am
by paso750
Congrats to the successful registration!.
Yes, that is the sprocket bolt. The 750S came with two different setups depending on the output shaft used (as is shown in the parts catalogue).
Why pull the master cylinder off first? Usually one starts with the simpler things ;) Is there enough fluid in the system and is the inner side of the clutch cover still dry? If that is all ok and if the system is bled again and there's still no pressure I'd check the master cylinder.

Re: 750 Sport restoration project

Posted: Tue Feb 06, 2018 10:33 am
by Andrew2
Thanks,
No worries I'll check the inside of the clutch cover first. There still seems to be plenty of fluid in the master cylinder. In my experience in the past the master cylinder has usually been the culprit though.

Re: 750 Sport restoration project

Posted: Mon Feb 12, 2018 4:49 pm
by paso750
here's one way to remove a dent :mrgreen:
https://www.youtube.com/watch?v=PaXsJiOfYJo

Re: 750 Sport restoration project

Posted: Mon Feb 12, 2018 5:32 pm
by Mirinn
:D :D :D

Re: 750 Sport restoration project

Posted: Tue Feb 13, 2018 3:30 am
by Andrew2
Now that's what I call a dent removal TOOL. :lol: :lol: :lol:

Re: 750 Sport restoration project

Posted: Tue Feb 13, 2018 7:22 am
by higgy
wonder how she managed to figure that one out

Re: 750 Sport restoration project

Posted: Tue Feb 13, 2018 3:50 pm
by Tamburinifan
:lol:

Re: 750 Sport restoration project

Posted: Tue Feb 13, 2018 4:37 pm
by randtcastell
I keep thinking if only she'd done the job "hands free" and hiked up that skirt...

Re: 750 Sport restoration project

Posted: Sat Aug 28, 2021 10:58 am
by Andrew2
G'day all.

Well I still have the 750 and I still haven't ridden it. What with other things going on and now the world going a bit crazy.. Anyhow seeing as I live in sunny New South Wales the penal colony where we're all locked down while the rest of the world gets on with life I thought now would be a good time to get the girl up and running ready for our release from this prison in 2025.
I only need to put on the chain, steering damper and seeing it's been so long I'll chain the timing belts.

Now here's the problem which has been there from the start. The clutch won't disengage. After removing the clutch cover I'm confronted with what appears to be a seized piston. I've got some penetrating oil on it at the moment and have tried a bit of heat but nothings happening. I've also got the clutch strapped to the bars. I'm hoping it might be freer in the morning.

So if it does free up I'm guessing the bore might be pitted. So what are my options. I have read the FAQ's etc but am a bit confused as to what parts I need. I've measured the piston and it seems to be the 26mm one. Any help would be greatly appreciated.

Cheers
Andrew

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Re: 750 Sport restoration project

Posted: Sat Aug 28, 2021 11:55 am
by paso750
It's been 3,5 years. :)
As can be seen from the seal, that is the piston that's often found on the 906 Paso. I'm certain you will not have to replace it.
After a longer while the piston can start to rust and it will seize in the cover. I bought two or three covers in the past that were that way. Penetrating oil is good. I'm guessing you sprayed that also inside the cover? If the cover was removed from the bike you'll need to reconnect it to the clutch line as the only chance to push the piston out is by using the hydraulic force of the clutch pump. Compressed air won't be strong enough unless you have a really big compressor but that could become dangerous. If the piston doesn't move try to push it in. Apply pressure via the pump then push the piston back in again. Don't try to get it out at once. It's better to move it in and out step by step and after a while it'll move more and more until finally you'll get it out. It'll also be less messy when the piston pops out than when attempting to doing it with a huge amount of pressure.
Once the piston is out you can clean it and sand it with very fine grit sandpaper. Don't use that for the bore in the cover tho! Use aluminium polish for that and do it by hand. That'll have to be washed off completely afterwards. As precaution I'd replace the o-ring with a new one or better the newer v-type seal, too. I'd apply a special grease on the cylinder wall before assembly but you don't have to. This is not (!) the typical brake caliper grease used for noisy brake pads or slide pistons on car caliper rebuilds (hence not i.e. Plastilube) but a special lube that's used for brake cylinder rebuilds or brake pistons. It does not react to brake fluid.

Re: 750 Sport restoration project

Posted: Sat Aug 28, 2021 12:16 pm
by Andrew2
Yeah, I've been a bit slack with the Sport what with other bikes and stuff. It's actually been sitting on the bike lift all this time waiting for the last little bit to be finished.

The liquid around the piston in the photo is penetrating oil. I also heated the cover in the hope it would expand a bit and let the oil work better. I did try pushing it in with a G clamp and socket but it didn't budge.I haven't removed the cover from the clutch line yet. I'm leaving it overnight to penetrate and if it's still seized tomorrow I'll take the clutch line off and pour some penetrating oil in from there.

Is it the same piston as in your article here.
http://forums.ducatipaso.org/viewtopic. ... 530#p56530

I was going to replace it with the new V seal but now I can't find the article on here that I saw the part number for it.