Harsh Cer Forks.

I had my brother hold a 2 1/2 pound lump hammer behind the link and had at it with a good size pin punch so I expect its ok. We will see.
 
Yeh, really doesn't need much to keep the side plate on the straight and narrow. Even seen a few bikes that have had the clip link missing (for who knows how long) and plates haven't ejected themselves off, so can't be much sideways pressure........................
 
I have done them with a lump hammer and something heavy behind at first, then not having any money I made myself up a thing like a small very strong g-clamp with a cup to press the sideplate and a point that splayed out the rivets, which worked quite well.  Somewhat later I got a proper tool and discovered how easy the system is with the right gear.  The side plate is a press fit, and there's a set distance it should go on to get the right compression on the o/x-rings.  Doing it manually that distance can be done wrong, whereas the tool sets it correctly in one go and you can't over-press it.
The DID tool has 3 setups, first to push out a pin to shorten or split the chain, a second to press the side plate on to the correct width, and a third to peen out the hollow rivet.  I never had a chain failure with any of the methods but the correct tool makes it a lot easier and sets things just-so.
The forces can be pretty high, I would advise against buying a chinese crap tool, their steels never seem to be good enough for such things.  The DID is not cheap (~$200) but will last your whole life.  There are probably decent ones out of Taiwan if it's sold by someone reputable (brand Bikeservice makes some nice stuff, COO Taiwan mostly).  But by then you're pretty much at the price of the DID anyhow.
Vince - you hijacked your own thread!  If you want my home made rivetter let me know.  It does not shorten the chain, I used to angle grind the heads off and punch the pins out which is a PITA.
 
I have an old Renals tool, it pushes but nothing else. I googled rivoting a link and watch a couple of vids, done correctly as Steve said its a lot more technical than you would think. I made sure the link could still pivot reasonably smoothly, it still pisses me off a simple clip link seems so hard to get for THAT chain that I bought.
 
Obviously the right tool is the best way to go , once you buy one you wonder why the fuck you. Bothherd with lump hammers etc, but if your that way inclined to get the plate seated square all you need is two 8 mm ring spanners and clamp to wind it on, then bash away with your hammers and punch
 
Hellooooo Helloooooo  (announce)

The Tigers won............ and nobody gives a fuck about ya chain any more Vince because, you no listen. (dunno)

I will spell it out for ya......... "Get a tool for the chain link" and you will be able to spend more time faffin around with ya front forks  (bolt)
 
Peter Stevens sell a DID lookalike for $99. Same as what I use and works well. Always grind the tops off the rivets before pushing them out to save the pin but. https://www.peterstevens.com.au/heavy-duty-chain-breaker-riveter.html
 
Last ride I was at it again on the Cer forked 3C.I wanted a softer ride on square edged  bumps as on a long day I would hit at least 3 or 4 bumps that would give a huge kick to the forks.My really old emulators came with 1 high speed compression hole. The later ones come with 2 holes and they are more compliant, in the attempted fixes on my Maz forked Pantah the US based Race Tech vintage expert Matt suggested I go the whole hog and try 4 holes.And I did, but I had gone to soft with the emulator spring preload ,at 2 turns and with the Pantahs catastrophic engine failure its been sidelined for a while.So before the last Laverda ride I pulled the emulators and drilled a 3rd hole in the high speed compression plate. One problem is the bike now runs a different front tyre is that's a variable in the mix. It had a T31 Bridgestone sports touring tyre and now its got a BT016 full blown sports tyre, both are Radials and both had the same pressures at 37psi.So we did thew full Putty Rd loop and to me its helped a lot. The bike has a much more planted feel, especially in those long fast rough as guts sweepers out near Jerries cafe. The bike was a bit loose before,nervous and kicking about.It feels much more planted.Where its the tyre or the extra hole I am not sure. I was 100% going to go to 4 holes after this but not till after the Snowy Run.What got me back to doing this was doing a day on Doug Homes old bike now owned by Marty. It had the best fork action I have tried yet. Compliant and firm, mine hopefully will be similar soon.
 
Good idea,no wait he is too big to do this too.Just to clarify,I could grit my teeth,hold the tank tight with my knees,and power through all this without much effort but it's fun to see what happens when I change something relatively easy to do. I have a mate who is elbow deep in shim changes in Cartridge forks on a KTM big twin, that's way beyond my comfort zone. So is most other high tech changes some do here, Quinton's and Tippies stuff for interest.I was surprised how little info there is out there on the stuff you can adjust on Emulators and its fun to see what effects it has.And the horrible fork issues I was having with the same fork on my Pantah and used on lots of Laverdas,now that fork is 100% better
 
A while back I rebuilt a pair of 38mm Ceriani forks and sold them to Maurice. He now has them on a bike and says they work really well. He reckons they're much better than an identical pair of forks on one of his other bikes. They had nothing fancy like emulators in them, just the basic old Ceriani damper rods. The only "custom" thing I did was to polish the insides of the fork stanchions and machine up new pistons for them with only a couple of thou clearance. I only did that because the old cast alloy pistons had expanded and were tight. I could have just turned them down to size but one of them I had to drive out with a hammer and drift, and it was fucked by the time it came out.  I figured if I was making one piston, I may as well make two. There was a slight difference in bore diameter of each fork leg. It was only a few thou, but I made the piston clearances so close that larger piston wouldn't fit in the smaller bore.

Anyway, perhaps the secret to getting Cerianis to work well is to set them up with polished piston bores and nice billet pistons with minimal clearance. 

BTW, the internal polishing was done by spinning the stanchion in the lathe chuck while shoving a broom handle in and out about a million times with various types of polishing contraptions on the end of it. Starting with emery paper, then steel wool, kitchen scouring pad and finally a soft mop with polishing soap.  Kept it up until the insides were nice and shiny (they were a bit dull and rough looking to start with). Seems it may have been worth the effort. 
 
I keep getting told by an unnamed individual that his bike forks are fine std.My Laverda forks were ok but what really got me going was the Horrible Maz forks in the Pantah,std they were virtually rigid, and after doing the usual upgrades for considerable cash they were just as shit.The cer tripals are not as offset as the Maz and what I think is with this laid out setup causing plenty of friction, add way to stiff a set of fork springs and you get a really stiff fork action.Any info on improvements is helpful,especially cheap ones.
 
I remember my standard Ceriani forks as being just fine and am sorry that I ever read the section on "improvement" on Laverdamania. The only reason I started was because a) I read that section (by Doug Home) & b) same as Cam I had a seized piston that needed to be belted out so the forks were apart anyway.

Now, after converting to Racetech emulators and ending up with forks that were worse than before I find that Racetech have decided that there needs to be an adaptor to force all oil through the emulator and this demands the use of Racetech springs as the Ceriani springs are now way too long and the preload is through the roof.

I say, leave well enough alone and stick with standard. Or if you are that pernickety about suspension do a conversion and put in complete new forks and triple clamps.
 
Dellortoman said:
A while back I rebuilt a pair of 38mm Ceriani forks and sold them to Maurice. He now has them on a bike and says they work really well. He reckons they're much better than an identical pair of forks on one of his other bikes. They had nothing fancy like emulators in them, just the basic old Ceriani damper rods. The only "custom" thing I did was to polish the insides of the fork stanchions and machine up new pistons for them with only a couple of thou clearance. I only did that because the old cast alloy pistons had expanded and were tight. I could have just turned them down to size but one of them I had to drive out with a hammer and drift, and it was fucked by the time it came out.  I figured if I was making one piston, I may as well make two. There was a slight difference in bore diameter of each fork leg. It was only a few thou, but I made the piston clearances so close that larger piston wouldn't fit in the smaller bore.

Anyway, perhaps the secret to getting Cerianis to work well is to set them up with polished piston bores and nice billet pistons with minimal clearance. 

BTW, the internal polishing was done by spinning the stanchion in the lathe chuck while shoving a broom handle in and out about a million times with various types of polishing contraptions on the end of it. Starting with emery paper, then steel wool, kitchen scouring pad and finally a soft mop with polishing soap.  Kept it up until the insides were nice and shiny (they were a bit dull and rough looking to start with). Seems it may have been worth the effort.
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And quite right is Cam these forks are fantastic they are progressive and compliant and perfect for what they are I would never try and transform a pair of 1970s forks into a modern equivalent.
You would be better off buying a monster like Terry has done Vince.
 
The first set of Emulators I fitted must be 20 years ago. I needed a better brake on my Husky 420cc 2 stroke Automatic enduro bike,that's with syntrivacaly operated  4 speed gearbox that changes by itself and its as fast as it sounds even now. Close the throttle on it going down a big hill and they have ZERO engine braking.It disengages the centrifugal clutches and freewheels. So I fitted a KX 125 43mm disc brake fork,great at big jumps completely crap on braking bumps. After fitting the $140 Emulators it was 100% better all round zero adjustments.Smooth as butter. So we have $170,cost now, for Emulators against 6 or 7 thousand Dollars and more for a Monster.Gee not sure that makes any sense at all but thanks for the unhelpful tip.
 
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