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Just a quickie, does anyone know if it is possible to buy a compact chainset to fit a mid 80's steel race bike? I have a Chas Roberts with Campagnolo Super Record chainset 53/42. Years ago, i could get up hills with this but now I'm struggling and a lot heavier than I was 28 years ago. I have already increased the freewheel lowest gear from 21 to 28 teeth but my lowest gear would be too tall to get me up the toughest hills locally. The bb is square taper and freewheel is 6 speed. Thanks.

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Neil753 [447 posts] 3 years ago
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Take a look at the "On One Touring crankset" from Planet X.
Looks similar in style to your existing Campag design, but rings are 34/48
Requires a 113mm BB (on a standard 68mm shell frame)
110mm BCD.

Alternatively, consider selling your old bike piece by piece and buy something modern with the proceeds. Some old stuff can sell for surprisingly big money on Ebay.

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Grubbythumb [61 posts] 3 years ago
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Before you do anything, take a look at the BCD (bolt centres) of your existing cranks, as it may be possible just to chance the chain rings.

I have a 1999 Raleigh with Shimano Tricolor 600 cranks, and just changed the rings to something more manageable. Spa Cycles are good for chain rings, but a quick google search will soon find the best prices.

If you do change the cranks, watch the tapers on your BB, as Campagnolo use a slightly different taper to Shimano and the rest. A quick look on Sheldon Browns web site will explain all.

Last, don't get rid of that Chas Roberts frame, whatever it is, it will be a peach. Old steel frames with modern running gear are the best of both worlds.

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Jack Osbourne snr [570 posts] 3 years ago
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+1 to trying smaller chainrings, although you'll be limited as to how low you can go.

1980's Campagnolo should have the 135 bcd standard, so you should be able to get down to 50t/39 easily enough, but remember your front mech will require to be readjusted.

Spa do a great selection but I would suggest you get a cheap one initially to test compatability both with the rest of the drivetrain and your legs.

If that's still too big a gear, you're into compact or triple chainset territory which may also require replacement of bottom bracket and front mech. You can still do that fairly cheaply, but it won't be super record.

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millhouse [30 posts] 3 years ago
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Thanks Neil 753, the On-One crankset looks like a good option. I have emailed Planet X to confirm that it will fit my Campag taper rather than a Japanese standard taper (as read on Sheldon Brown).
I bought a new carbon bike recently but to be honest I prefer the ride of my old Roberts. Only downside is not being able to fit later parts and there is a limited amount of parts available or very expensive old stock Campagnolo. When I stopped cycling in 1986, things like 7 speed freewheels were just coming in. So coming back to cycling in 2013 has left me with a lot of catching up to do (technology and fitness).

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Neil753 [447 posts] 3 years ago
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millhouse wrote:

Thanks Neil 753, the On-One crankset looks like a good option. I have emailed Planet X to confirm that it will fit my Campag taper rather than a Japanese standard taper (as read on Sheldon Brown).
I bought a new carbon bike recently but to be honest I prefer the ride of my old Roberts. Only downside is not being able to fit later parts and there is a limited amount of parts available or very expensive old stock Campagnolo. When I stopped cycling in 1986, things like 7 speed freewheels were just coming in. So coming back to cycling in 2013 has left me with a lot of catching up to do (technology and fitness).

No probs.
My suggestion is to convert to 7 speed indexed. You can easily find 7 speed downtube levers 2nd hand, go for a 7 speed 105 rear mech (cheap and reliable), and just fit a new HG 14-28 freewheel (still plenty around NOS on Ebay - don't go to a shop as they charge double) and an HG40 chain (normally a fiver). If you've got a 126mm rear hub (which is likely) then add a 2-4mm spacer so that the chain won't rub on your seat stay (with that 14 sprocket). You'll end up with a nice range of gears from 90 to 32 inches (on a 700x25).
Super Record BBs are worth money, so why not sell the whole BB assembly and fit a new axle as well.

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millhouse [30 posts] 3 years ago
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Now you have really got me thinking  39
I already have a 7 speed freewheel 14 - 28 on the bike, but the rear mech does not shift past 6th; You are right, my hubs are 126mm, but when I place the HG70 chain onto 7th it drags on the seat stay, so where would I place the spacer to clear it? Indexed gears would be great, I recently fitted some Simplex retro friction levers in place of the Campag ones which are a slight improvement but still need alot of micro adjustments which is a pain while riding. I have noticed a knocking sound while on the 3rd sprocket (21). On inspection it looks like the chain is too close to the next (24) sprocket.
If I can get the set up that you are suggesting, this bike will be a great ride. I'm happy to go the route of ON-One crankset, 105 rear mech, shimano 7 speed d/t levers. When you say a 7 speed 105 rear mech, can I go for a new 10 speed or will it need to be an old 7 speed, are they interchangeable? Most new drivetrain parts now are listed as 9/10 or 11 speed, I'm never sure if any of these can be used on my 6/7 speed set-up?
Many thanks.....

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Neil753 [447 posts] 3 years ago
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Your chain is rubbing your seat stay because your hub was only designed for a five speed (or an "ultra six", which was a narrow Shimano freewheel that was the same width as a standard five speed). What compounds the problem is the slightly greater diameter of a 14 cog, as opposed to the likely 13 cog on your six speed freewheel.

You need to add the spacer between the existing spacer (on a Campag Record hub it will be silver) and the lock nut that touches the inner side of the dropout. 2mm may be enough, but it depends on the angle of the seat stay (which will be a function of your frame size). You may need to strip the hub and move the cones and spacers along a bit, so that you still have enough axle sticking out on the gear side. Try 2mm and, if that's enough, then slide everything along by half that figure, ie 1mm.

One word of caution, when using old Campag Record hubs, is that heavier riders can bend the axle far more easily than with "cassette" hubs, where the gear side bearing is much closer to the rear dropout. But, if you're getting back into cycling then you will no doubt be losing weight, so it things may be fine.

The "spacing" for indexed gears is determined by the gear change lever. But, inevitably, there are thousands of 7 speed indexed rear mechs out there, sitting in people's garages, so I would say Ebay may be your cheapest route to indexed gear nirvana. There's 194 of them listed on Ebay as I write this. Just ensure that the gear "capacity" of a rear mech is sufficient for your choice of gears (see Sheldon Brown's site). Those Simplex retroshifters make good money too, so potentially helping to offset your conversion costs.

Obviously things have move on a bit since you were last riding around, but you'll find indexed levers on the downtube a major improvement from friction based downtube levers. Indexed levers can normally be switched to friction mode too, if you have an adjustment problem when out on a ride and you don't want to stop.

If you have a vintage machine, this is the way to make a very useable bike.

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Jack Osbourne snr [570 posts] 3 years ago
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There is also the drastic alternative... the complete refurb and update.

I took my old training bike (and first racing bike) and converted it from 7 speed to 9 speed compact with ergo shifters, which although it ended up costing several hundred pounds (new drivetrain, wheels etc etc) has resulted in a beautiful machine which rides every bit as well as it looks... and affords my ageing knees a much easier time on hills.

If you strip off the existing Super Record stuff and Ebay it, you'll probably get most of the cash required to do this.

One word of caution though - you would need your rear dropouts spread.. it can be done, but does occasionally result in the need for a weld or two .

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Welsh boy [316 posts] 3 years ago
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Matt eaton [742 posts] 3 years ago
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If you're changing rear mech don't worry too much about how many 'speeds' it was designed for.

Most modern(ish) rear mechs will work with almost any number of gears. I'm currently running an old '7 speed' rear mech on a 9 of 10 set up on a seven speed cassette hub. It's all Shimano (I know campag compatibility is not always so simple). I've just bought a more up-to-date set of hubs from ebay and will be running a true 10 speed soon and don't anticipate having to change from my '7 speed' derailier.

If you really want to improve gear range you might be able to use a 7 speed cassette hub with an '8 of 9' or '9 of 10' set up, it's worked a treat for me. If you use a long-cage derailier and an MTB cassette you might even be able to avoid changing chainrings/cranks at all. This is bound to be more pricey than changing a single chainring but might be another option which would really update your bike.

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nostromo [55 posts] 3 years ago
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Send the Roberts back to the framebuilder in Croydon or somewhere like Argos in Bristol and have the rear dropouts resized for a modern wheelset. I did this on an old 80s Peugeot and have fitted a new wheelset (105/Mavic) with a 28t cassette and a Stronglight Compact crankset (50:34). It works a treat.

You can get the crankset for about £70 new from most bike retailers and even Tesco!!!

Alternatively, please sell me your Roberts and buy a Boardman from Halfords.

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Matt eaton [742 posts] 3 years ago
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Just an added update, I'm now running a 10 speed cassette on a '7' speed derailier - no problem.

TBH, converting a 126mm steel frame to 130mm doesn't require much 'conversion' at all, just squeeze a 130mm hub in there. We're talking about flexing the stays by 2mm each and steel can handle this. I believe that some of the first production 130mm hubs actually had bevelled cone nuts to make them slide into 126mm frames more easily.

I should probably say that this advice comes without any warranty. I'm a tinkerer by nature and do these sort of things without hesitation (tonight I re-drilled a 36 hole rim to work with a 32 hole hub for instance - seems fine so far in case you wondered but not riden properly yet). If you don't feel confident in making decisions about whether it's safe to do this sort of thing you should probably hold back, or get on to Sheldon Brown for inspiration.

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nostromo [55 posts] 3 years ago
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But can I still buy your Roberts?

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pcaley [39 posts] 3 years ago
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Try a Stronglight Impact compact chainset with 48/34 rings. It is 10 speed compatible but works fine with the 8 speed set up on my old Dawes road bike.

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millhouse [30 posts] 3 years ago
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Thanks for all the good advice, especially Neil753. I have now bought an FSA Vero chainset 34/50 that came with a sealed type bottom bracket. I ordered a pair of 7 speed indexed downtube levers shimano 105 from Poland, and a 10 speed 105 rear mech and a Sunrace 7 speed freewheel. I have spaced the rear hub by 2mm and this has allowed the fit of a 7 speed freewheel.
I built this bike in 1985, still got most of the receipts, won some road races on it so it has alot of sentimental value.
I'm not sure if my Campag Super Record will change the compact chainset. I had my old hubs built into Ambrosio clincher rims to replace the old Mavic GP4's (no more sewing and gluing).

looking back, I could have bought a Felt from Wiggle for £430 and used it through the winter!!!