Campag Chorus 10spd - Compact Chainset

[Paul Walters]

I'm thinking of changing the 2006 10spd Campag Chorus chainrings on my Orbea Onix Giro from their original 53/39 set up to a 50/34 ish compact. I'm having a hell of a job finding such an animal, as the current Chorus groupset is 11spd, and from what I can gather, that crankset can only be used with the specific 11 spd bottom bracket.

Help.

 

[youngoldbloke]

Any good? Chain Reaction

 

[Paul Walters]

Hi YOB, I did see that in my googling, but further investigation seems to suggest that the U torque crank can only be used with the U torque BB, and I am not sure what BB is actually fitted. I bought the bike in 2006/7 and tbh, it's been in storage for probably the last 3 years. There's nothing wrong with the current groupset, it's just my knees are taking a pounding on the Devon hills :-(.

I think I might be able to get Veloce 10spd chain rings in 50/34, but I didn't want to down-spec the bike. And, I was hoping for a cheaper solution than changing the entire groupset.

 

[StuAff]

Any 10 speed crankset will work (assuming BB compatibility with your frame). You certainly won't need to change the whole group. You will almost certainly need a new crankset to go compact- AFAIK 135mm BCD compact rings do not exist.

 

[Paul Walters]

Thanks Stu.... any idea how I find out which BB would fit the frame ? When I bought the bike, I had little knowledge of such things...... I suppose I could just take it to my LBS and ask them to sort it though? When I asked them the other day (in passing really), they suggested that the 11spd one referred to by YOB in Chain Reaction would be suitable, though I have my reservations about the compatibility of 11spd chain rings with a 10spd chain and cassette.

 

[ColinJ]

How about an alternative approach ...?

I have similarly hilly terrain to deal with so for that reason, I have just converted my Cannondale from a 53/39 double Chorus 10 speed groupset to a 48/38/28 triple. I love it on the hills now.

I bought a Stronglight triple chainset from Spa Cycles for about £75 and a Shimano UN55 bottom bracket for about £10. I was able to use the original left shifter (it has plenty of ratchet stops to cope with the extra ring) and the front derailleur also worked once I lowered it to fit the smaller big ring. I think my Chorus was from about 2004 and am not sure if yours would be the same, but I suspect it would be.

I haven't sold my old chainset and BB yet, but I bet I can get £40+ for them to offset the cost of the new parts.

 

[derrick]

Whats the tooth count on the rear block?

 

[accountantpete]

You will have either a square taper (less common) or Carbon Ultra Torque chainset presumably. The former is the traditional BB whereas the UT has a big hole on either side and the words Campagnolo Ultra Torque written on the outer edge of this hole.

Replacement wise - all you need are compact UT cranks and possibly new BB cups.

I would have thought that 11 speed cranksets will work but they are very costly - I think that they will run on the old 10 speed Cups if you already have UT otherwise a new set will cost you £18 plus £8 for the installation tool.

Have a look on ebay for lightly used sets.

Personally I have used Record, Chorus and Centaur carbon chainsets - the main difference is the bearings which doesn't make that much noticeable improvement so I would go for the Centaur if you can find them in the arm length that you want.

http://www.ebay.co.uk/itm/Campagnol...sure_cycling_bikeparts_SR&hash=item2ed1f07876

Avoid a later Campagnolo variant called Power Torque!!!

 

[Paul Walters]

Derrick. the cassette is a 12-25. There is a replacement 12-29 available, and I wonder how much difference that would make.

Pete, the chainring has "Campagnolo Power Torque EPS" on the side, and I can't see if it's a square taper. The fixing is Allen bolt in the centre. There are no "big holes", so I suppose it's a square taper. Given my usual experience with all things mechanical, this crankset will be a limited edition only ever fitted to 6 bikes between August and September 2006, and discontinued immediately afterward.

The BB cups are visible, but are smaller diameter than the shell, which appears to have an annulus of 5mm of metal showing around the BB.

 

[ColinJ]

Derrick. the cassette is a 12-25. There is a replacement 12-29 available, and I wonder how much difference that would make.

You can actually get a 12-30 now, which would give you a bottom gear 25/30 of what you have now, or nearly 17% lower. That's quite a big step, but may not be quite enough to save your knees and it costs twice what the 29 tooth one does! (The 29 bottom gear would be 25/29 of what you have now, or 14% lower.)

Pete, the chainring has "Campagnolo Power Torque EPS" on the side, and I can't see if it's a square taper.

It isn't!

 

[Crankarm]

Try Geoffrey Butler Cycles in Croydon which is where I got several new OE 10spd UT Campag Chrous chain sets, oh God, must have been 5-6, maybe 8 years ago as they were selling them off mega cheap. They might still have some or recommend something. HighOnBikes might be able to help although I think he sold all his old Campag stock. I got several Record UT double and chain sets from him at very good prices, Chorus UT bottom brackets, double and triple, plus Chorus cassettes (8spd) again at good prices. Although I now use Shimano Ultegra 6500/6600 9spd as I bought quite a bit of old stock of this when it was being sold off cheap at CRC to last me many years.

Have you thought of getting some TA chain rings 50/34 instead?

 

[accountantpete]

Derrick. the cassette is a 12-25. There is a replacement 12-29 available, and I wonder how much difference that would make.

Pete, the chainring has "Campagnolo Power Torque EPS" on the side, and I can't see if it's a square taper. The fixing is Allen bolt in the centre. There are no "big holes", so I suppose it's a square taper. Given my usual experience with all things mechanical, this crankset will be a limited edition only ever fitted to 6 bikes between August and September 2006, and discontinued immediately afterward.

The BB cups are visible, but are smaller diameter than the shell, which appears to have an annulus of 5mm of metal showing around the BB.

The next step is to find out what BB you require. Bikes come with either a threaded BB or a push fit BB (BB30 etc)

See the variations in this ad and see if there is any lettering on the side of the BB Cups
http://www.wiggle.co.uk/campagnolo-...360392924&ci_src=18615224&ci_sku=5360392924uk

Otherwise you will need to look up the bike spec.

 

[Paul Walters]

It's probably this one, though whether Italian or English ??

http://www.wiggle.co.uk/campagnolo-chorus-double-tapered-bottom-bracket/

Oh dear......

 

[Paul Walters]

OK, here's another option that has been suggested...... how feasible is it to change the crankset to Shimano 105 and replace the BB with a Shimano unit..... run campag on the back end, with a campag chain, and use the ratchet campag front shifter with the 105 chainrings/cranks? A friend of mine has just changed one of his racing bikes from 105 to Ultegra DI2 and has 105 bits available at silly money..... Anyone done this or know if it's even possible ? I'd always thought there was no cross compatibility between Shimano and Campag?

 

[accountantpete]

It's probably this one, though whether Italian or English ??

http://www.wiggle.co.uk/campagnolo-chorus-double-tapered-bottom-bracket/

Oh dear......

You have a Power torque set of cranks haven't you? So it won't be that one.

You can certainly use Shimano cranks but I would pop down to the LBS and find out what BB shell you have as that is the vital bit.