Author Topic: Campagnolo 8sp shifters (Ergo?)  (Read 4014 times)

Re: Campagnolo 8sp shifters (Ergo?)
« Reply #25 on: 08 December, 2019, 09:16:06 am »

….On bb spindles, I don't know the official size norms but it is not true to say they are all the same as BSC. Been there, done that in most combinations, had the cup that was too wide and didn't clear the crank, or was too narrow to get the lockring on more than two threads, or had a bit of radial play when all was tightened up.....

what you describe is 'normal' if you start randomly mixing and matching parts between makes/models of BB. My point was that in any one model of BB the spindles are usually the same between French and BSC versions, i.e. the spindles have the same shoulder width.   This arises because French and BSC threaded BB shells are almost exactly the same width as one another.

FWIW if you use a short-arm simplex (eg 'prestige') rear mech it will handle a ~28T sprocket but it won't have enough total capacity to (safely) run a wide-range triple at the front. For that you will need a long arm mech.  IIRC these will usually also handle a slightly larger sprocket too.

cheers

Re: Campagnolo 8sp shifters (Ergo?)
« Reply #26 on: 08 December, 2019, 09:05:52 pm »
26t was a Spécialité TA Cyclotouriste thing in this vintage. I will leave someone else the problem of sourcing that!
Velo Orange and (I think) Sun Race make repro Cyclotouriste chainsets, so it shouldn't be hard. Google for 50.4 bcd.

They are a pretty good match, with the only real difference being increased clearance between crank arm and large chainging to allow for wider modern front mech cages.

Re: Campagnolo 8sp shifters (Ergo?)
« Reply #27 on: 08 December, 2019, 10:18:16 pm »
FWIW I've always been more than a bit leery about that era of simplex long-arm mech; I've seen plenty go into the rear wheel or just break for no good reason (*).  However for many years there wasn't a good alternative, not off the peg anyway; eventually campag started to make a long arm 'Rally' mech but until then folk were a bit stuck if they wanted a robust RD that mounted to a 'modern' gear hanger.   So for a long time  a common modification was to take a RD with a good parallelogram design (i.e. not made from worryingly  floppy plastic) and to extend the arm somehow.  The campag Nuovo Record mech was pick of the bunch  for this, and (just like the later production Rally models) the guide pulley was usually moved downwards/backwards to allow a larger sprocket to be used.

I have seen a few mechs like this and some are beautifully made and others pretty much look cobbled together.  The one below (picture found on the interweb)  is a bit of both and (allegedly) came fitted to a Rene Herse.



It uses some simplex parts and some DIY parts  in the cage, nailed onto a campag parallelogram.

(*)  It is quite telling that in the UK especially, machines which used the widest range gears, such as touring tandems, were still  commonly fitted with the somewhat archaic  chainstay-mounted 'cyclo standard' RD (or similar) right until the late 1960s or early 1970s; these were one of the few mech designs that had enough capacity and were likely to last more than five minutes.

Anyway if you want a 'period correct' bike with wide range gears then both conversions of mechs and chainstay mounted RDs are fair game.

cheers


Re: Campagnolo 8sp shifters (Ergo?)
« Reply #28 on: 08 December, 2019, 11:51:41 pm »
here's another one



and if you fancy making your own Rally type mech you can buy cage plates to convert a NR mech e.g.

https://www.veloduo.co.uk/collections/gears/products/soma-nuovo-retro-derailleur-cage-plates

cheers

Paul

  • L'enfer, c'est les autos.
Re: Campagnolo 8sp shifters (Ergo?)
« Reply #29 on: 09 December, 2019, 08:26:34 am »
I always thought that ‘mech’ was short for mechanism but it looks from your photos that it might also be short for meccano.
What's so funny about peace, love and understanding?

Re: Campagnolo 8sp shifters (Ergo?)
« Reply #30 on: 09 December, 2019, 09:59:47 am »

….On bb spindles, I don't know the official size norms but it is not true to say they are all the same as BSC. Been there, done that in most combinations, had the cup that was too wide and didn't clear the crank, or was too narrow to get the lockring on more than two threads, or had a bit of radial play when all was tightened up.....

what you describe is 'normal' if you start randomly mixing and matching parts between makes/models of BB. My point was that in any one model of BB the spindles are usually the same between French and BSC versions, i.e. the spindles have the same shoulder width.   This arises because French and BSC threaded BB shells are almost exactly the same width as one another.

FWIW if you use a short-arm simplex (eg 'prestige') rear mech it will handle a ~28T sprocket but it won't have enough total capacity to (safely) run a wide-range triple at the front. For that you will need a long arm mech.  IIRC these will usually also handle a slightly larger sprocket too.

cheers

yes "mix'n match", after a couple of decades passing through several garages, boxes and the like the chances of a sultry 40yr old bb axle in my posession still being anywhere near it's cups (which may or may not have come from the donor clubmate) are pretty slim. The one thing you can't mix is french and BSC cottered sets. They are quite definitely different because the axle diameters are different and the cranks don't swop (at least if they are old enough!).

I should have remembered that a Prestige changer will take a 28t sprocket, the number of times I have done it. The mech swing and the cable pull have always restricted me to 6sp with these mechs though.
here's another one



and if you fancy making your own Rally type mech you can buy cage plates to convert a NR mech e.g.

https://www.veloduo.co.uk/collections/gears/products/soma-nuovo-retro-derailleur-cage-plates

cheers

Now that has given me ideas! For me, not for anyone else! Although I still think that my preference for older touring mechs is the Duopar. I had an Eco which had what appeared to br a bronze secondary paralellogram. Having heard disparaging remarks about this mech I have recently seen one offered on e-bay which had a rivetted steel secondary paralellogram and looked a bit crap but mine was lovely (don't ever let me meet the tea leaf wot pinched that bike from my ex!)
26t was a Spécialité TA Cyclotouriste thing in this vintage. I will leave someone else the problem of sourcing that!
Velo Orange and (I think) Sun Race make repro Cyclotouriste chainsets, so it shouldn't be hard. Google for 50.4 bcd.

They are a pretty good match, with the only real difference being increased clearance between crank arm and large chainging to allow for wider modern front mech cages.

That is very useful. Thanks.
FWIW I've always been more than a bit leery about that era of simplex long-arm mech; I've seen plenty go into the rear wheel or just break for no good reason (*).  However for many years there wasn't a good alternative, not off the peg anyway; eventually campag started to make a long arm 'Rally' mech but until then folk were a bit stuck if they wanted a robust RD that mounted to a 'modern' gear hanger.   So for a long time  a common modification was to take a RD with a good parallelogram design (i.e. not made from worryingly  floppy plastic) and to extend the arm somehow.  The campag Nuovo Record mech was pick of the bunch  for this, and (just like the later production Rally models) the guide pulley was usually moved downwards/backwards to allow a larger sprocket to be used.

I have seen a few mechs like this and some are beautifully made and others pretty much look cobbled together.  The one below (picture found on the interweb)  is a bit of both and (allegedly) came fitted to a Rene Herse.



It uses some simplex parts and some DIY parts  in the cage, nailed onto a campag parallelogram.

(*)  It is quite telling that in the UK especially, machines which used the widest range gears, such as touring tandems, were still  commonly fitted with the somewhat archaic  chainstay-mounted 'cyclo standard' RD (or similar) right until the late 1960s or early 1970s; these were one of the few mech designs that had enough capacity and were likely to last more than five minutes.

Anyway if you want a 'period correct' bike with wide range gears then both conversions of mechs and chainstay mounted RDs are fair game.

cheers



I have had the honour of using one of those Cyclo mechs in good condition on a tandem which was a sheer joy, really smooth and reliable. I have also had the misery of using one with worn out pulleys which shipped the chain at every gear change. Simplex piston mechs on 50's bicyclettes suffer the same problem and the pulley is a smaller diameter so you can't get round it by fitting a modern one (it fouls on the cage)

Re: Campagnolo 8sp shifters (Ergo?)
« Reply #31 on: 09 December, 2019, 10:00:43 am »
I always thought that ‘mech’ was short for mechanism but it looks from your photos that it might also be short for meccano.

You're not that far from reality when talking about 1970-s mechs. Back then you could still disassemble them and interchange/machine parts for them.

Re: Campagnolo 8sp shifters (Ergo?)
« Reply #32 on: 09 December, 2019, 11:37:19 am »
re. small pulleys in RDs; I don't know what size is required for the older simplex mechs but it might be possible to use a pulley from a shimano crane mech. One (the third?) version of the crane RD came with unusual 9T  pulleys, made in solid steel. They last a very long time indeed and (provided 9T is the right size and you are prepared to make a centre bushing if required) they might be just the job for an oddball mech like the simplex?

BTW if you buy an old crane mech just for the pulleys note that

a) not every one had the small steel pulleys and
b) the ones that did are just as happy with 10T pulleys

so provided you are prepared to fit new 10T pulleys you still have a 'correct' Crane mech to use or sell on.

BTW the difference in British and French cottered BB spindles arises because one is 5/8" and the other is 16mm. Only 0.1-something mm difference, but this is quite enough to cause problems!

cheers

guidon

  • formerly known as cyclone
Re: Campagnolo 8sp shifters (Ergo?)
« Reply #33 on: 13 December, 2019, 03:52:53 pm »
Joe, had 13-30 6sp back in the day with a super lj simplex rd on my first peugeot - worked great! but then I ran 42-52 on the chainset, not a triple...

Re: Campagnolo 8sp shifters (Ergo?)
« Reply #34 on: 13 December, 2019, 07:21:17 pm »
I should have remembered that a Prestige changer will take a 28t sprocket, the number of times I have done it. The mech swing and the cable pull have always restricted me to 6sp with these mechs though....

Normally if it works with 6s then 7s is also possible.  The RD stroke required for 'standard' 6s is 5 x 5.5mm = 27.5mm and the stroke required for 7s is 6 x 5mm = 30mm.  Which is 2.5mm more, obviously.  However with 7s you are definitely using a narrow chain and it is usually (*)   possible to run the chain closer to the inside face of the RH dropout than with 6s. The net effect of this is that the low gear sprocket is often only ~1mm further leftwards with 7s  than with 6s, i.e. well within reach of a mech that will handle 6s.  8s is a different matter though.

(*) -but not always admittedly, depending on how the frame is laid out, and if the simplex RD mounting sticks out much; I have fitted modified screws here sometimes-

cheers


Re: Campagnolo 8sp shifters (Ergo?)
« Reply #35 on: 13 December, 2019, 08:17:11 pm »
I should have remembered that a Prestige changer will take a 28t sprocket, the number of times I have done it. The mech swing and the cable pull have always restricted me to 6sp with these mechs though....

Normally if it works with 6s then 7s is also possible.  The RD stroke required for 'standard' 6s is 5 x 5.5mm = 27.5mm and the stroke required for 7s is 6 x 5mm = 30mm.  Which is 2.5mm more, obviously.  However with 7s you are definitely using a narrow chain and it is usually (*)   possible to run the chain closer to the inside face of the RH dropout than with 6s. The net effect of this is that the low gear sprocket is often only ~1mm further leftwards with 7s  than with 6s, i.e. well within reach of a mech that will handle 6s.  8s is a different matter though.

(*) -but not always admittedly, depending on how the frame is laid out, and if the simplex RD mounting sticks out much; I have fitted modified screws here sometimes-

cheers

I must admit to not having tried it with 7sp, that being something that came into my life after the Prestige. My problems have been related to friction shifters without enough cable pull (the worst being trying to use stem mounted shifters that hit the top tube on 7sp; must have been a super LJ mech - although the Sachs ones are not very different and they are made for 7 indexed and handle 8 no trouble in friction mode).