FAQ: clutch pushrod order info

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bobnorton
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Re: FAQ: clutch pushrod order info

Post by bobnorton » Fri Mar 22, 2013 3:38 am

There must be a knack to replacing the outer spring box and keeping the bits from falling out, either that or i need longer bits or something is wrong.Tried heavy grease, and clutch center adjuster all the way in or falling out.

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Re: FAQ: clutch pushrod order info

Post by BevHevSteve » Fri Mar 22, 2013 6:20 am

Put everything in place inSide the engine. The thickest piece that sits in the clutch actuator lever, that is greased up and stuck into the lever. Now bring the cover up and carefully put in place. Easy.
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Craig in France
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Re: FAQ: clutch pushrod order info

Post by Craig in France » Fri Mar 22, 2013 7:32 am

Hi Bob,

Check your components against this - the 860 rods are NOT exactly the same as the Darmah.

Also - and I don't know your engine number, so this may not apply: but I note that the long rods, 0759.16.240, were shorter before engine number 851194.

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HTH.

Craig

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Re: FAQ: clutch pushrod order info

Post by BevHevSteve » Fri Mar 22, 2013 7:48 am

Oh yeah Craig - you know that last rod is shorter on the earliest of 860, and, the clutch is different as well. I forgot about that....
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bobnorton
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Re: FAQ: clutch pushrod order info

Post by bobnorton » Fri Mar 22, 2013 10:39 am

I seem to have the later engine and the earlier shorter rods !, mine are 110mm when they should be 113.5 mm. But i don't see why i should not just use the earlier set up with the extra roller. I have a suspicion that a roller may have fell into the clutch center,and as the clutch is firmly stuck its comming to bits . Trying to work out how to unwire the starter ,looks like i may have to remove the rear light and mudguard first to get at the solenoid , Who designed this??.Shurly shum mistake.

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Re: FAQ: clutch pushrod order info

Post by wdietz186 » Fri Mar 22, 2013 6:43 pm

Bob, I'd keep the balls and rollers as they are and get a new,or make a longer''bullet". The 3-4mm you need is probably from wear in the actuating lever. If run dry the bullet drills itself into the lever as the other end wears away.With a longer actuating lever you will probably need the extra length anyway because it will require longer travel to disengage the clutch[once you get it working of course].
Bill

bobnorton
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Re: FAQ: clutch pushrod order info

Post by bobnorton » Fri Mar 22, 2013 8:33 pm

Hi Bill, yes using Brancato Lever, and yes appear to be 3-4 mm shy. But suspect all not right at the clutch end ,soon be in there. --Later, found 2 rollers loose in the center,one is likely from my efforts, and a unlocked nut ,not very tight.No washers under the springs.

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Re: FAQ: clutch pushrod order info

Post by Spagjet » Mon Jan 13, 2014 7:41 pm

I have endlessly played with my clutch over the years and thought I would share a bit of the resultant madness (conclusions)

The 'pushrod' has to be made up of a heap of short bits at the actuator arm end as when you think about it the cup on the actuator arm would travel in an arc, not a straight line so the short bits and peices for all intents and purposes just make the pushrod 'flexible' and minimises the chance of jamming.

To make the last bit (between actuator arm and sprocket) stay put while re-installing sprocket cover nothing works better than sticking it there with a big thumb-full of black grease in the cup on the arm. It should be greased anyway.

The ball bearing and short cylinders can be any ball bearing (they are all hardened steel) and any short roller bearing (again, all hardened steel) that has a good clearance fit in the bore. It's really not a mystical thing. it's a pushrod in sections.

The last bit of pushrod with the flat end and round end wears out (gets pushrodded to death) eventually, mine did. I saw it as an opportunity to more finely adjust the position of the actuator arm in the sprocket cover slot. You don't want it actually touching the sprocket cover of course but the closer the better. A couple of reasons for that, the clutch action at the lever will be at it's easiest when the actuator arm is at 90 degrees to the clutch basket, again, not rocket science to see why that would be the case. All cable clutches have got a bit of "settle/stretch" between first moving the lever and any movement at the actual clutch basket. I have found through a million hours of #ucking around over many years that if the actuator arm is very close to the case (most aren't with 'factory' pushrods) when the lever starts to be pulled on , by the time the clutch plate actually starts to move the arm is at 90 degrees.

You adjust this by chucking your original bit of pushrod that goes into the actuator arm in the rusty fruit juice tin with all the other Ducati debris and replacing it with the end of a car engine pushrod. You have to cut the end off a car pushrod with a cutoff wheel which attests to it's hardness (they are harder than the original bit), and then carefully clean the flat end off nice and smooth and square on a grinder and a knife stone (and then wash it out with kero). If you want to move the actuator arm out in the case by 6mm (for example) you only need the last bit of pushrod to be 2mm longer (or so, it's a bit a fitting job to get it just the way you want it).

It doesn't matter if you bugger it up on the first couple of tries, buy a few old pushrods from the car wrecker while you're at it, you get two ends on each one.

The other good thing about doing this is that they are hollow so you get to pack them with black grease which can help keep the cup on the actuator arm lubricated as there is a little hole in the end of the ball set into the end of pushrods.

I have done this on a few squarecases, it works awesome, especially when you have also lengthened the actuator arm itself. The best way to do that is to just cut it about an inch under where it protrudes from the engine and weld a three inch section of allen key to each side and just leave an inch or so gap between the ends of the actuator arm. As long as the allen key sections don't touch the inside of the engine case. Allen keys are both hard and tough, and welding them to the sides of the arm means the arm won't foul either the sprocket or the case as it doesn't make the arm any thicker than it already was. It's a hell of a lot stronger than trying to butt weld the two bits of arm, I have known people who have tried this and come to grief.

Another good trick for making your clutch easier to use is to gently bend your clutch lever a bit straighter (very gently bit by bit or you'll snap it off) so you don't have to reach out so far with your fingers to get to it. You might lose a bit of travel this way but you can make it up by not having any clearance when you adjust your clutch. You're supposed to have a few millimetres of slack in the cable when the clutch is engaged but you really don't need it.

Another way to get over the lessening of lever travel by finessing the lever a bit straighter is to check the pivot hole in the lever, they are almost always worn into an egg shape. Take the lever off the bike and wash it, measure the biggest part of the worn hole with dial calipers, get the closest drill size to it you can, put the drill bit in a tap holder, gently twist the drill through the worn hole to round it back up and then make a little steel bush on a lathe to take up the clearance, you only need a few thou clearance on the pivot bolt. The tap holder idea works great, because the hole is like an egg, if you try and do it in a bench drill, the bit digs into the lever and turns it into a fuckleknucker.

All these adjustments together makes the clutch a million times better that it was believe me.

Oh yeah, oil your clutch cable, or none of it means a thing....

bobnorton
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Re: FAQ: clutch pushrod order info

Post by bobnorton » Wed Jan 15, 2014 12:55 am

Hi Spagjet, Thanks for your comprehensive reply, I have fitted a long arm and its set at the end of the slot (extra ball or roller in there somewhere),this also means that the arm retains the short rod if the cable breaks.My main problem was the retaining in position of the end fittings while fiddling with it all. Would not like to have to do it on the road . I don't think that well greased rods are a significant factor in clutch drag.I think the non adjustable clutch springs are a problem and I have achieved a better action after a bit of packing to even up the lift.Next time its apart I will dump the extra roller and lengthen the short fat rod as you suggest. Norton clutches can be fitted with a radial bearing in the pressure plate ,sounds good? fancy some more fiddling?. :(~

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Re: FAQ: clutch pushrod order info

Post by Spagjet » Wed Jan 15, 2014 5:46 pm

hey Bob,
my clutch used to be a real bastard when I first got the bike which is why I have mucked around with it so much. I think you're on exactly the right track with the idea that it's so hard to actually install the sprocket cover because there is too many bits in there (like you say someone has probably put an extra ball in there to get the arm further out in the slot) which would make it really hard to know if the last bit (short rod that sits in the cup on the actuator arm) is lining up with the hole in the middle of the sprocket at you try and ease the sprocket cover back in place (especially considering the other two things you are trying to line up at the same time with GTS selector boxes). If you make a new longer rod and dice one of the balls it might solve the whole problem for good.
I like making my bikes better not only yo use but also easier to pull apart and put back together, there's nothing worse than parts that are hard to get off and back on when it doesn't have to be that way. I want to enjoy working on my bikes.

There's a couple of other things I have figured out over the years about Ducati wet clutches I might as well add while I'm at it.

Getting the rods, rollers, and balls out without having to pull the clutch cover off: You get a bit of thick fencing wire, stick it in a vice with just a few millimetres sticking out and mushroom the end down so it looks like a big nail head, then dress it up dead flat on the end with the grinder, then arc it over the car battery terminals a half a dozen times to magnetise it. You then make sure it's nice and straight along it's length and use it to draw the bits out of the hole in the middle of the sprocket one by one. You have to do the thing with the wire as all the "magnet on a stick" tools you buy are too big to get in the hole.

Clutch basket springs: sometimes the clutch doesn't seem like it's disengaging because the end clutch plate rises off the rest crooked. It has to be dead level or you need another few millimeteres of travel to get it to disengage enough (I've known people who thought they had a problem with their gearbox or selector box that fixed it with this idea). It's because the little springs are starting to collapse, you have to pull them out and make sure the are all exactly the right length. If they aren't the obvious way is to buy a new set but if there's only one (or two) that are more sagged than the rest you can try putting a packing washer under just those two and see if it improves the clutch. If there's three saggy ones and three (relatively) good ones you can arrange them good, bad, good, bad, etc right around and try and even it up that way. All you have to acheive is a dead level top clutch plate when it moves.

Slipping clutch. If the clutch slips too much (all Ducati wet clutches will slip if you give them enough pills) you can try and pack all six springs with washers or even get a hold of some stiffer clutch springs (they are available) and either try them or if that makes the lever action too heavy try three light, three heavy springs. trouble is with heavier springs is that they soak up more of the lever travel before the clutch starts to move, apart from the fact that a heavy clutch lever is a pain in the arse. I have known several cases where people have had slipping clutches and done all that and still had slip, there's a couple of great tricks to try before you start looking for new clutch plates (that's if you have measured the whole clutch pack and it's still within the seviceable limit). You can get the steel plates and give them a light scruff with a bit of rough sandpaper and/or get the fibre plates and give them a blast with Brakekleen and a scruff (just enough to take the glaze off, you don't want to sand them down under the service limit). Before you put them back together give all the plates a coating of 10 weight machine oil. I have seen this work more than once. When the clutch is engaged the plates are all tight together, it's only when you pull the lever in that they are apart so the heavy engine oil can't really get in all that easy because of centrifigal force. Bikes with roller bottom ends need heavy oil which is exactly what a wet clutch doesn't need.
bobnorton wrote: Norton clutches can be fitted with a radial bearing in the pressure plate ,sounds good? fancy some more fiddling?


I really like the thrust bearing idea in an engineering sense but I don't really think it's needed. I have replaced the "bit of pushrod" once in over 20 years (I run my clutch with zero cable clearance to maximise lever travel) and I always like to keep everything as absolutely simple as I can so there is as few a parts as possible to fail. Especially when low flying......

Oh yeah, I re-read what I wrote about lengthing the actuator arm. I said you need to cut it an inch under where it sticks out of the engine. That's not right, you need to cut it two inches down as you need an inch or so to weld the allen key section to and you want and extra inch sticking out of the case which is the whole point. There's just enough room in there to have an inch gap between eack end of the cut arm and an inch of weld on either side. Also forgot to mention that both the actuator arm and the allen key material are a lot harder than mild steel so it's a good idea to use low hydrogen welding rods, and don't quench it, just throw it out in the paddock in the sun and go get it later.

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ColinS
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Re: FAQ: clutch pushrod order info

Post by ColinS » Fri Feb 14, 2014 6:52 am

Hi Guys,
I'm just fitting an extended clutch actuating arm to my SSD and took the opportunity to check out / clean / lube the pushrod assembly. Interestingly, with engine number 904143, I found the exact same arrangement of rollers, balls and rods as shown in the 860 diagram (see an earlier post). It works just fine so will go back in just as I found it. It was all very clean and well-lubed, so didn't really need touching but at least I now know that it's OK.

Cheers

Colin
Steve, thanks for making this a sticky, it saved a good deal of time looking for the info.
admin edit: No problem Colin, that's the whole point of this forum.... To have an easy to search resource for us to find the info we need on our bevel drives...
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Re: FAQ: clutch pushrod order info

Post by herbg » Sun Sep 13, 2015 1:49 pm

I slackened my clutch cable adjustment knob to measure about 1-2 mm of free play at the actuator arm. Then, I tightened the knob just so there's tension on the cable but the arm can still wiggle manually. There's lots of "floppiness" in the clutch lever using this adjustment. Is that normal?

Conversely, when the clutch lever adjustment knob is fully turned out so that there is full tension on the cable and the lever is taught, the clutch engages very late. I have to let the lever out almost to the end before it engages with the engine ... making it very difficult to ride and causing engine stalling.

I suspect the clutch is pooched as it was not replaced during the rebuild.

Any thoughts on this?
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2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

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Re: FAQ: clutch pushrod order info

Post by herbg » Sat Sep 17, 2016 3:50 pm

Since I've got the clutch & shifter assembly apart on the 900SS, I ordered the Clutch Rod & Ball (small) Kit (among other items) from BevelHeaven.

Finally getting around to removing the existing rods and balls from the bike (with the excellent tips from this post in hand). My 1978 900SS is a bit of an odd ball - unlike any other Canadian 1978 model as this bike was purchased in Europe. It's effectively a leftover 1977 blue/silver build with engine 087599 but many 1978 features.

Anyway, to my surprise, it appears that rod no. 47 is missing from the end of the assembly. See the photo below:
IMG_20160917_1745013___.jpg
Then, I measured this rod & ball assembly for future reference. Here's the measurements, using the numbers highlighted in the Parts Manual:
Clutch Diagram from Ducati_1975-76 750-900SS Spare Parts Catalogue.jpg
No. 45: 26.35mm X 7.85mm (Length x Width)
No. 44: 7.91mm x 7.93mm
No. 46: 7.91mm
No. 44: 7.91mm x 7.93mm
No. 43: 113.45mm x 5.97mm
No. 47: 6.50mm x 6.14mm
No. 43: 113.45mm x 5.97mm
No. 47: Missing

There is a minor discrepancy with rod No. 47. from BevelHeaven's kit as it measures 5.99mm x 6.00mm. While I'm sure the 0.50mm isn't a big deal, I wonder which is correct. I'll be installing BOTH No. 47 rods from Steve's kit which should get things back to normal.

I'm also wondering about the measurements for Rod. No. 45.

Anyway, I'm interested in your comments on what I measured.

Cheers,
Herb...
_________________________________
2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

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