Rear linkage bearing removal

[Marinus]

I have a small amount of play in the back end. When the bike is on the centre stand and I apply weight to the seat so that the back wheel is just touching the ground, there is about 2mm of play before the suspension engages.

I don't notice it in the handling but the guy at the testing station wants it all tight before he will give me a warrant of fitness.

I have taken the back wheel off and removed the linkage from the bottom of the shock and the rear part of the linkage from the swing-arm. There seemed to be no slack in any of these or in the main swingarm bearing. I can feel some play in the front bearing where the linkage connects to the steel frame of the bike.

My questions are:

Could this small amount of play be my problem or should there be some play there?

Can this bolt be removed without removing the rear cylinder header pipe? As the bolt has to come out in that direction.

The bearing of the linkage (arm) where it mounts to the frame has the following bearing:

HK 2030 INA VWX

I don't really want to go there If I can avoid it.

Cheers Marinus

[Desmo_Demon]

2mm doesn't seem like a lot of slack to me, especially if you consider the distance between the wheel and suspension components. Without having the distance and doing the math, I'd guess that 2mm of play is less than 0.5mm of play at the suspension. Consider the factory tolerances of the bearings and add them all up, and you'll probably still be within factory specifications of the bearings.....but, as I said, I'm guessing with this.

For removal of the suspension bolt, I'm not sure. When I did all the suspesion work/inspection of my Paso, I had to remove the header pipe to remove the swingarm. I'm not too sure that you can remove the bolt without removing that pipe. I did notice a difference between my '87 and '88 frames, though. One has an access hole for a socket on each side, and the other frame only has ONE access hole for the bolt. Instead of having an option of installing the bolt from either side, the one frame was so that It could only be installed one way. Without being in front of the frames, though, I can't tell you which one was which from memory (I actually have three frames).

I wish you luck with it......


Edit - I just remembered that when I was going through my suspension, I noticed that some of the suspension bolts were missing washers. With them missing, there was more side-to-side play in the linkage. Having a less-than-competent previous owner list working on this bike may have been part of that problem, but you may want to check your bike with the parts list to make sure that nothing is "missing"...unless you know the history of the bike since new.

[Marinus]

Thanks for that. I was looking through your own site and saw that you mentioned that you had to take the header off as well to remove that bolt.
My bike wasn't registered until 1990 so I guess it was one of the later 750s made and sat in a dealership in Italy before it was bought by the first owner. How it got to NZ from there I don't know.

I look at your photos and think my bike looks brand new compared to your projects.

Cheers M

[Desmo_Demon]

I was looking through your own site and saw that you mentioned that you had to take the header off as well to remove that bolt.

I ended up removing the rear header pipe and the slip-ons, but I was removing the complete swingarm assembly, so I don't know if it is necessary to remove the rear header for just the one bolt that you are trying to remove, but.....it wouldn't surprise me if it was necessary. Wish you luck with it.

I look at your photos and think my bike looks brand new compared to your projects.

Actually....I don't find that funny at all. :laugh:

[Marinus]

Like you say the paso is a project bike. They are supposed to be imperfect.

If it puts a smile on your face, I don't have a Ducati 748 monoposto sitting in my garage for if I get frustrated working on the PASO.

[Finnpaso]

My bike wasn't registered until 1990 so I guess it was one of the later 750s made and sat in a dealership in Italy before it was bought by the first owner. How it got to NZ from there I don't know.

Marinus, If that Your avatar is from Your bike and U HAVENT polished that triple clamp, then Your bike is one "of the first 750 Pasos built". ONLY first "patches of 750 Pasos" came with that silver coloured upper triple clamp. Surely it can be, that its put to street very late... Anyway, its build very early.

[Gwenadu]

Could this small amount of play be my problem or should there be some play there?

Can this bolt be removed without removing the rear cylinder header pipe? As the bolt has to come out in that direction.

I had the same problem... and I had to remove the rear exhaust pipe to tighten the bolt.No loose now.

[Marinus]

Antti You may well be right. It may be one of the older ones.
Desmo - Demon mentioned that some of his frames had a hole on only one side behind the centre stand to get that shit bolt out and he thought the later frames had one on each side. Mine only has the one so is likely an earlier bike. I will look up the numbers. I just assumed it was one of the last ones because it was registered so late and was in such good condition. Never mind. The polished aluminium is one of the things I really like about the bike.

Back to the suspension:

I did go though dismantling half the bike to get that one bottom bolt out only to find that like the rest of the bearings it looked almost like new in there with all the bearings nicely packed with clean red grease and no movement. The little bit of slack that there is is where the bearing sleeve fits over the bolt. I'm sure the hardened sleeve has not worn on the mild steel bolt and all the bolts are good with very little marking on their ribbing. So like Skins said to me find someone less fussy to pass the WOF.

I took the main swing arm bolt out because I had done everything else I thought why not that as well. But I could not get the swingarm out! I have pulled and leaved and still no joy.

I take my hat to you who have done this. In the manual it said just pull it out. It doesnt mention that that back header is stuck in there and won't extract up or down.

So I've given up on that job and will reassemble. There is only 1mm of play left to right at the very end of the swingarm and once again from what I could see the bearings looked well greased in there.

So after dismantling half of my bike again I think the only thing I have achieved is a little peace of mind and in the moments of frustration while I was looking for something to polish while I though out my next move I found that the bolts on the rear sprocket were half undone and only finger tight. That sprocket has been loose for a while I just never thought it was the bolts and thought there was some play designed into it.

I guess my frustration has a good outcome.

[Gwenadu]

[Marinus, If that Your avatar is from Your bike and U HAVENT polished that triple clamp, then Your bike is one "of the first 750 Pasos built". ONLY first "patches of 750 Pasos" came with that silver coloured upper triple clamp. Surely it can be, that its put to street very late... Anyway, its build very early.
_________________quote].

...And the last 750s had Digiplex ignition system (like mine -Nb 754 377-).

Alain.

[Finnpaso]

Just right Alain! Pitty, that just that last version with Digiplex wasnt so good, as "Kokusan" version... Many of those Digiplex have failed(also in 906s)down and it didnt have any "advantage" compared to "Kokusan version"... Propably best version was with Öhlins rear chock, Kokusan and with 40mm diameter headers and open exhaust... Anyway its good to know VIN number.... Maybe we have to make someking of "vote about VIN numbers and whatkind of ORIGINAL STUFF everybody have in they bike" to have better data compared to Ducati factory... Someone make such topic???? :laugh:

[Gwenadu]

Digiplex wasnt so good, as "Kokusan" version...

Italian stuff vs Jap :umm:

[Marinus]

Just had a look at the number on the steering head and it's :
DGM 52055 OM
and it has the Digiplex ignition system.

[gail]

Yeah agree with Skins, Find less fussy test police, Play can be theoretical, Takeups in the suspension unit could be the cause of the problem if it is not sideways movement, If you have ever had the displeasure of participating in the jap suspension technology "advancements" of the seventies and eighties where the general consensus was that the more complexity was built in the better it was, till it hit the dirt , crud, water and lax owners maintenance regimes , I'll hand you a beer to cry in. I won't waste a full one on this though.
Unitrack , Prolink, Monoshock etc., etc. Almost one use items, the only shock they couldn't control was the huge expense of replacing all the dozens of component parts, besides trying to prise apart the whole sordid box of tricks once she was cactus!. Give me the days of the twin shock, uncompomising , cheap, stiff, difficult but fun? they almost made people ride within their capability, if excessive speed was not a factor. I must be a luddite with a visa card on my 907,always remember "A thing of beauty is not a joy forever". Check out my wife!
Hope you have a bit of joy soon ,Cheers

[Desmo_Demon]

I don't have a Ducati 748 monoposto sitting in my garage for if I get frustrated working on the PASO.

Sometimes it isn't a good thing. In the last 3-4 months, I have not only worked on the Paso, but I've also been working on a valve adjustment, fuel filter change, sprockets and chain, fiberglass work, timing belt adjustment, rocker inspection, clutch slave clean and inspection, clutch plate inspection, oil and filter change, and installation of a quick change sprocket carrier on the 748......but I've also had to do a timing belt adjustment and oil/filter change on the ST2......I seem to never have any free time when owning multiple Ducatis! :laugh: