Yet Another Cycling Forum
General Category => The Knowledge => Topic started by: mzjo on 04 December, 2019, 09:51:10 pm
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This is probably a subject that has already come up.
A clubmate has acquired an old randonneuse frame and last night was asking about how to organise the transmission. My mate Christian, who is a proper mechanic has asked for my help as a renowned bodger and mixer of improbable bits. The frame is a Meral, all french threads and standards. Our friend would like to fit a triple (thinking of a TA Cyclotourist, I think, although where he's going to find one in good condition I don't know)and he likes his Campag transmissions. The frame would have been made probably for 5sp (although 6 can usually be made to work). For the time being the state of the bb axle and bearings is unknown. The remit would therefore be triple chainset with a 26t granny ring, some form of Campag mechs and shifters and, probably a 6sp freewheel (also probably french threaded; I think he has a set of wheels).
I know from experience that Shimano 8sp and Sachs 7sp mechs and shifters will work reliably with 6sp freewheels (even unindexed) from most makers.
1 Do Campag front (lh) shifters for triples have indexed positions or are they more like friction shifters?
2 Has anyone tried using an indexed Campag shifter and rear mech with a 6sp freewheel?
3 Do Campag 8sp shifters have the same pull ratios as Shimano?
4 What would be the correct Campag gears for this sort of thing? Mirage is the name that comes into my head but I really don't know much about Campag since 1950's vintage Gran Sport.
I really think that the chainset solution is Spa but that would mean much shorter axles than we are likely to find in french bbs. (I also think that the real way forward is retapping to italian but there is no-one in Limoges capable and willing to do such a thing.)
A lot of the questions are because I have a vague memory that up to and including 8sp Shimano and Campage were more or less interchangeable. I am not sure that with a 6sp freewheel any spacing incompatibility is going to cause much of a problem (although it would be nice to know that a Shimano indexed freewheel would work)
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1. All 8s ergo shifters (and many others subsequently) are 'ultrashift' and have a micro-ratchet for the LH shifter which has enough cable pull for all 'road' triple FDs (be they campag or shimano).
2. May be possible by using a shimano mech with a campag 8s shifter
3. No
4. Correct? meaning what? Period correct? Need to know date of frame/parts really.
Easiest thing to do would be to use conventional DT friction shifters; Ergos have to be indexed with the RD and the whole setup would need to be changed if the pitch in the freewheel were to vary. FWIW you can obtain/build cassette hubs down to 126mm (or even less) and fit a shortened cassette (retaining the pitch of the sprockets) if you like. So 8,9.10s etc parts can be used, with a little cunning, to give 7,8,9s setups (if one sprocket is deleted in the shortened cassette).
cheers
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BTW I just checked and if you use an 'old' (pre '99 more or less) campag 9s ergo with a 7/8/9s shimano RD, you get almost exactly 5.5mm RD movement per click, which is a pretty good match for most (standard spaced) 6s freewheels.
cheers
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This is probably a subject that has already come up.
A clubmate has acquired an old randonneuse frame and last night was asking about how to organise the transmission. My mate Christian, who is a proper mechanic has asked for my help as a renowned bodger and mixer of improbable bits. The frame is a Meral, all french threads and standards. Our friend would like to fit a triple (thinking of a TA Cyclotourist, I think, although where he's going to find one in good condition I don't know)and he likes his Campag transmissions. The frame would have been made probably for 5sp (although 6 can usually be made to work). For the time being the state of the bb axle and bearings is unknown. The remit would therefore be triple chainset with a 26t granny ring, some form of Campag mechs and shifters and, probably a 6sp freewheel (also probably french threaded; I think he has a set of wheels).
I know from experience that Shimano 8sp and Sachs 7sp mechs and shifters will work reliably with 6sp freewheels (even unindexed) from most makers.
1 Do Campag front (lh) shifters for triples have indexed positions or are they more like friction shifters?
2 Has anyone tried using an indexed Campag shifter and rear mech with a 6sp freewheel?
3 Do Campag 8sp shifters have the same pull ratios as Shimano?
4 What would be the correct Campag gears for this sort of thing? Mirage is the name that comes into my head but I really don't know much about Campag since 1950's vintage Gran Sport.
I really think that the chainset solution is Spa but that would mean much shorter axles than we are likely to find in french bbs. (I also think that the real way forward is retapping to italian but there is no-one in Limoges capable and willing to do such a thing.)
A lot of the questions are because I have a vague memory that up to and including 8sp Shimano and Campage were more or less interchangeable. I am not sure that with a 6sp freewheel any spacing incompatibility is going to cause much of a problem (although it would be nice to know that a Shimano indexed freewheel would work)
My Dawes Galaxy (circa 1989 vintage) is currently (and has been for decades) running around with a Shimergo system **exactly** as you describe.
Campagnolo Mirage 8-speed shifters with a Shimano 6-speed freewheel.
To answer your specific questions:
1: The front shifter is more like a friction shifter, there are definite clicks but close enough to micro adjust the front mech. (Added to that, I am running a TA Cyclotouriste triple with a Sachs-Huret **double** front mech - never missed a shift in 25 years)
2: I have a Shimano Deore LX rear mech (6/7/8 speed vintage from memory) running from the Mirage lever. It occasionally overshifts around the 2nd and 5th cogs, but nothing that can't be fixed by shifting across 2 and back 1! Apparently early 9-speed Campag Ergo shifters are pretty much a perfect fit for Shimano 6-speed, but cost twice as much on Fleabay!
3: No, but that doesn't stop bodging a reliable system!
4: Mirage is the levers I have, beware that Mirage comes in 8- and 9-speed versions.
Hope this helps. If you need any more info, or photos give me a shout.
Edit: X-post with Brucey
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1. All 8s ergo shifters (and many others subsequently) are 'ultrashift' and have a micro-ratchet for the LH shifter which has enough cable pull for all 'road' triple FDs (be they campag or shimano).
2. May be possible by using a shimano mech with a campag 8s shifter
3. No
4. Correct? meaning what? Period correct? Need to know date of frame/parts really.
Easiest thing to do would be to use conventional DT friction shifters; Ergos have to be indexed with the RD and the whole setup would need to be changed if the pitch in the freewheel were to vary. FWIW you can obtain/build cassette hubs down to 126mm (or even less) and fit a shortened cassette (retaining the pitch of the sprockets) if you like. So 8,9.10s etc parts can be used, with a little cunning, to give 7,8,9s setups (if one sprocket is deleted in the shortened cassette).
cheers
Re 2 I have done this with Shimano mech and shifter, ditto Sachs indexed dt lever and Sachs mech and Sachs lever with Shimano mech. I can't remember having the occasion to try Shimano shifters with the Sachs mech but I don't foresee a problem. Thus if it is possible with Ergo and a Shimano mech why not Ergo with a Campag mech - or are we into the magic of Shimergo?
re 4 As in which generations or models of Campag kit would be the best suited to this type of operation? Period correct is not possible I think, the frame must predate indexing and Ergos.
Yes my personal preferred option would be dt levers, indexed or friction to taste (there are some very good and cheap 8sp indexed levers out there, one isn't limited to the cheapest Shimano 6sp). I am less convinced by building a shorter cassette - surely one would need a shorter freehub or else the dish of the wheel would be increased with reduction in width. A common problem with these older frames is a sprocket restriction imposed by the design of the drop-outs. Even my Moser, which is relatively modern (1985-1987) suffers from this. I also can easily find appropriate hubs if needed from my stock of bits. However it's not for me so the options that Christian or I would use are not necessarily appropriate. FWIW this is for gentle touring, not period rallies!
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you can build any shimano 7s freehub down to 126mm and the wheel will have about the same dish as normal (where 'normal' is the amount of dish on a 8s/130mm wheel). Further improvements in dish are possible provided you are prepared to do a little machining/modification. Campag did (briefly) make 7s cassette hubs too.
7s shimano cassettes are spaced 5.0mm pitch which is a perfect match for campag 8s shifter/RD. IME the worst you will have to do is to add a washer on the RHS of a 7s cassette hub to get it into an awkward frame with clearance on the smallest sprocket. However I suppose if the clearance is truly abominable you could simply delete the smallest sprocket and use a spacer of some kind instead; still six gears this way.
cheers
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Thanks everyone, I think that that's given the answers for saturday's post-walk restaurant - where this is on the discussion menu.
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If your clubmate decides he wants a pair of 8 speed campag ergos, I have some that I bought second hand and never got around to using (I stuck with the dt shifters).
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You might like to have a look at the sprocket pitch information (https://www.cyclinguk.org/cyclists-library/components/transmission-gears/derailleur-gears/shimergo) here. Your vague memory relates to the way that Shimano up to 7-speed and Campag to 8-speed cassettes stuck with earlier freewheel sprocket spacings. If you could get the frame re-spaced to take a 130 OLN =7-speed wheel (instead of 126 OLN = 6-speed), you could just use a 7-speed freewheel and 8-speed Campag kit. I've a bike on which I was doing that (till the rear hub flange broke). I think Shimano is a distraction here, given your friend's preference, and you should use pure Campag (except the freewheel, where anything you can get hold of, Shimano included, is fine - although getting good ones is harder now).
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Mirage 8 speed Ergopowers have a distinctive shorter life as the better ones. The difference is that Mirage ergopowers have a plastic inner shifter while the higher level ones have a metal one. The plastic one is prone to breaking.
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7s road was originally 126mm, and has about the same dish as 8s 130mm. Most hubs that accept a standard-spaced 6s cluster will also accept a 7s cluster with little or no modification.
7s 130mm came later and was originally for mountain bikes.
Shimano hubs are hardly a distraction; as I mentioned before if you want to use the bike a 7s shimano cassette hub is arguably the most practical choice.
cheers
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Mirage 8 speed Ergopowers have a distinctive shorter life as the better ones. The difference is that Mirage ergopowers have a plastic inner shifter while the higher level ones have a metal one. The plastic one is prone to breaking.
My Mirage 8s levers have a shift paddle that has a plastic end (where your fingers bear against it) but is made of steel where it attaches the rest of the mechanism. Are they all like this, I wonder? I have seen the same construction used on 'Chorus' 8s ergos too.
FWIW the internal parts of most Mirage 8s ergos appear to be identical to those fitted in record and chorus models.
cheers
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Mirage 8 speed Ergopowers have a distinctive shorter life as the better ones. The difference is that Mirage ergopowers have a plastic inner shifter while the higher level ones have a metal one. The plastic one is prone to breaking.
My Mirage 8s levers have a shift paddle that has a plastic end (where your fingers bear against it) but is made of steel where it attaches the rest of the mechanism. Are they all like this, I wonder? I have seen the same construction used on 'Chorus' 8s ergos too.
FWIW the internal parts of most Mirage 8s ergos appear to be identical to those fitted in record and chorus models.
cheers
Yes, exactly this one. I've had 2 break when I was still using 8 speed Ergopowers, of that one issue was on the return leg of LEL 1997, just before the ascent of Yad Moss.
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Shimano hubs are hardly a distraction; as I mentioned before if you want to use the bike a 7s shimano cassette hub is arguably the most practical choice.
Yes, apologies. I was thinking of Shimergo derailleurs from the OP's question, where there didn't seem to be much advantage, given that Campag used the "standard" spacing anyway. Since Shimano 7-speed cassettes do too, then using their hubs (which are probably easier to get than Campag 8-speed, which in any case I believe had issues with splines not being strong enough) would be an option.
I may have muddled my spacings in my previous post. I was thinking of spreading from 5- to 6-speed, and got the spacings wrong. I had forgotten that 8/9/10 use wider hubs (https://www.sheldonbrown.com/frame-spacing.html). Need to check on that for the bike I mentioned, where I'm planning to replace my broken 6-speed screw-on Campag hub with a 9-speed cassette one.
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Yes, exactly this one. I've had 2 break when I was still using 8 speed Ergopowers, of that one issue was on the return leg of LEL 1997, just before the ascent of Yad Moss.
did the plastic part crack/come away from the steel bit? I have had something similar happen with early shimano STIs (ultegra 8s) too; those had paddles which were also made in a similar way. IIRC cracks appeared in the plastic part well before they actually failed, and of course they saw lower loads because in those shifters the paddle is just a release trigger (to pay cable out) rather than something which pulls cable. I wonder if there is something (QA problem, detail design change, or usage) that provokes/inhibits this kind of failure? The reason I wonder this is that my mirage ergos look to be in danger of wearing out everywhere else before the paddles fail.
If there is a systematic difference in parts that might fail or not maybe it can be identified; I may go over mine with a strong magnet, to see how far the steel part extends into the plastic overmoulding.
cheers
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Indeed, it came away. As far as I remember the metal base is very thin but long and the plastic paddle just seperates from it.
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that tallies with what I found when I offered a strong magnet up to my paddles earlier; not only does the steel piece extend nearly the full length of the paddle spine, it also extends backwards into the broadest part of the paddle too. Presumably should the plastic come away from the steel, you still have something you can use temporarily?
cheers
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that tallies with what I found when I offered a strong magnet up to my paddles earlier; not only does the steel piece extend nearly the full length of the paddle spine, it also extends backwards into the broadest part of the paddle too. Presumably should the plastic come away from the steel, you still have something you can use temporarily?
cheers
No, the still part is too thin to exert serious pressure.
The root cause wasn't the paddle though. That particular frame was made when Ergopower/STI was just out. Cables run through a small tube below the bottom bracket, directly on the powder coating. After a while the shifter cable digs it's trench into the powder coating, creating greater friction. So you need to exert more force at the paddle, resulting in too much pressure on the paddle. (And in my case at the end an old shoulder injury playing up again).
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IIRC such cable guides were specifically forbidden by most manufacturers for indexed gear installations of any kind. They can usually be fitted with a length of plastic liner of some kind, but I have found that unless the liner itself is fitted with drain holes, it tends to fill up with crud and if there is enough road salt, even stainless steel cables can start to corrode.
BTW when fitting a new cable to any potentially worn underbracket cable guide, a new cable can be fractionally wider than the old one, and can almost immediately be much draggier than it should be, because it (literally) jams in the groove worn by the old cable. In any case more tension begats more friction, so if the shift is baulky for any reason, a disproportionate increase in cable tension may be required because of the increased friction.
Currently Campag recommend that you measure the force required at the shifter end of the cable during installation, e.g. in order that
a) the RD can overcome the cable friction on upshifts
b) the RD spring tension is correct for the shifters (not every campag RD is compatible with every shifter, even if the cable pulls are the same)
c) that the cable friction isn't so high that downshifts routinely overload the mechanism.
Anyway my Mirage levers have had worn hoods (worn smooth twice over), worn internals, worn brake lever bushings, you name it, but the steel/plastic paddles are showing no signs of distress. But then they probably haven't been used with super-draggy cables either.
cheers
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I have gained a bit more information and insight into the machine that raised my initial post. It is actually fitted with Simplex changers and retrofriction dt levers. Our friend wants to keep it "dans son jus", which means as original, except that he was talking about putting Ergos on it and wanting a triple chainset with a 26t granny ring. All french threaded of course! We have already told him that Simplex mechs and Ergo shifters aren't going to mix. Our problems will revolve around simply finding bb axles of the right length and trying to get probably 6 sprockets et the back (on Campa NR hubs, I think). The capacity of the mech is another problem entirely.
Neither Christian nor I know the rear width OLN. I think probably 122, he thinks possibly 120 (which I find improbable, although it could be even smaller if the frame is old enough and made for 4 sprockets!). Some very careful measuring is going to be needed!
On another subject our walk and resto was postponed until next saturday. Christian was too slow off the mark and the restaurant didn't have the space available!
edit: just to say thank you all all the same for posting. The information is all filed under "useful, do not lose"!
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edit: just to say thank you all all the same for posting. The information is all filed under "useful, do not lose"!
And in that spirit:
If your clubmate decides he wants a pair of 8 speed campag ergos, I have some that I bought second hand and never got around to using (I stuck with the dt shifters).
I've dug them out. They are Athena CARBON* (Campag's caps, not mine). Nice condition. The brake and mech levers are all alloy, no marks/scratches, and the ratchet wheels are metal. I've never fitted them, but in the hand all the clicks are there. The hoods show some wear but no tear.
(*no idea what, if anything, is CARBON in there? I suppose it might refer to some other component of the groupset but, in the 8s era, I've no idea what that might have been)
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5s hubs were 120mm OLN and some (quality) frames were still being made until about 1980 with 5s 120mm spacing. Cheap frames carried on being 120mm for a while after that. For a while folk had frames built to all kinds of intermediate spacings including 122mm and 124mm on the basis that you could use a service spare wheel in a race whether it was 120mm, 126mm or something else.
BITD I ran 'compact/ultra 6s' freewheels (which used 5.0mm pitch vs 5.5mm for 'standard 6s') which needed hubs of at least 120-122mm, but would go into frames built for 120mm 5s. However the closest you will get to this in new parts (rather than NOS) today is buying a 7s freewheel and deleting the last sprocket; some (not many these days) have the 7th sprocket screwed onto the 6th and are easily modified this way. You need to use 7/8s chain with this sprocket spacing of course.
Most folk would automatically reset the frame to 126mm or wider but some folk leave it be and keep with 5s freewheels; it is getting less easy to do this but it is possible.
Keeping the originality and having lower gears is of course a pair of largely incompatible objectives. I think the closest you will come to it is if you fit a long-arm simplex mech and convert the original chainset to a triple. Often this is easier than it might sound because there are (were) such things as tripleiser chainrings. I've even made my own eg by using stronglight 99 chainrings and drilling a 42T chainring so that it can be used as a 'middle ring' on a larger BCD with a smaller chainring bolted to it. The good news is that the BB spindles used in French threaded BBs were the same as BSC ones, so as long as you have good French threaded cups, you are 'only' looking for a longer spindle.
cheers
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5s hubs were 120mm OLN and some (quality) frames were still being made until about 1980 with 5s 120mm spacing. Cheap frames carried on being 120mm for a while after that. For a while folk had frames built to all kinds of intermediate spacings including 122mm and 124mm on the basis that you could use a service spare wheel in a race whether it was 120mm, 126mm or something else.
BITD I ran 'compact/ultra 6s' freewheels (which used 5.0mm pitch vs 5.5mm for 'standard 6s') which needed hubs of at least 120-122mm, but would go into frames built for 120mm 5s. However the closest you will get to this in new parts (rather than NOS) today is buying a 7s freewheel and deleting the last sprocket; some (not many these days) have the 7th sprocket screwed onto the 6th and are easily modified this way. You need to use 7/8s chain with this sprocket spacing of course.
Most folk would automatically reset the frame to 126mm or wider but some folk leave it be and keep with 5s freewheels; it is getting less easy to do this but it is possible.
Keeping the originality and having lower gears is of course a pair of largely incompatible objectives. I think the closest you will come to it is if you fit a long-arm simplex mech and convert the original chainset to a triple. Often this is easier than it might sound because there are (were) such things as tripleiser chainrings. I've even made my own eg by using stronglight 99 chainrings and drilling a 42T chainring so that it can be used as a 'middle ring' on a larger BCD with a smaller chainring bolted to it. The good news is that the BB spindles used in French threaded BBs were the same as BSC ones, so as long as you have good French threaded cups, you are 'only' looking for a longer spindle.
cheers
I have a 13-30 6sp Normandy freewheel in french threading sitting here somewhere that is in good condition so if the mech will accept it that should be ok (or it will be 28t bottom on a 5sp Maillard Course). I don't know the state of Christian's stock but he gave most of it to me a couple of years ago; anyway I think we can do a freewheel, one way or another. A period chainset with a decent granny gear is more problematic. 30t is relatively easy, 26 may be a bit harder to find.
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. Not really a problem however since we are in France and there are more french cup and cone bb sets than english kicking around. I have at least a couple of spindles in double and triple lengths.
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28 should be very easy as Stronglight had it for it's 99 triple and similar models.
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28 should be very easy as Stronglight had it for it's 99 triple and similar models.
Yes indeed (I have a 30t and a 32 for mine) but I think that the 26t was a Spécialité TA Cyclotouriste thing in this vintage. I will leave someone else the problem of sourcing that!
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….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
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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.
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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.
(http://www.angelfire.com/oz/z27/as03.jpg)
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
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here's another one
(http://2.bp.blogspot.com/-V6_dlvE7JAg/UJmC5FQVNgI/AAAAAAAAAlA/yPWqqknGgqA/s400/DSC02679.jpg)
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 (https://www.veloduo.co.uk/collections/gears/products/soma-nuovo-retro-derailleur-cage-plates)
cheers
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I always thought that ‘mech’ was short for mechanism but it looks from your photos that it might also be short for meccano.
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….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
(http://2.bp.blogspot.com/-V6_dlvE7JAg/UJmC5FQVNgI/AAAAAAAAAlA/yPWqqknGgqA/s400/DSC02679.jpg)
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 (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.
(http://www.angelfire.com/oz/z27/as03.jpg)
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)
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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.
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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
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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...
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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
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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).