CX 36/46 MEGAEXO to Compact 34/50

by joebee9870   November 9, 2013  

Ive just got a Colnago World Cup and it comes with a FSA 36/46 Megaexo and I would like to change it to a Compact 34/50 but I could live with a 36/50 set up if that is possible. Do I just change the big ring to the 50 or the whole Chainset. Also Could the Megaexo BB be changed to a BB30 set up? Any advice would be great.

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I think you should be just able to change the rings as long as you get one with the same bolt centres. Don't for get to raise your front mech.

Not sure on the BB as I have never had the pleasure of taking a Colnago to bits, but suspect you can't as BB30 is a larger diameter to Megaexo and BB30's are press fit as opposed to screw in. (It all depends on the bottom bracket shell).

have fun,

Paul

Velotastic !

Too many hills, but too little time.

badback's picture

posted by badback [266 posts]
9th November 2013 - 20:48

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Should be a 110 bcd chainset, so changing chainings is eminently possible. FSA rings usually have the bcd clearly marked on them, so simply check that before buying replacements. As Paul says, you'll need to reseat the front mech upwards.

Forget about bb30 on that frame though. It is possible, but pointless.

HOWEVER... Whilst you've got the chainset off, take the Megaexo bottom bracket off and bin it. They truly are shockingly bad. Putting them on a CX bike is laughable as the seals seem to be made of bog roll.

Take your pick of Hollowtech 2 bottom brackets as a replacement as almost any over a tenner will be miles better than the FSA.

My eyes prefer Celeste, my bum prefers titanium.

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posted by Jack Osbourne snr [304 posts]
9th November 2013 - 21:11

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Thank you Paul. I think that is what I will do.

posted by joebee9870 [57 posts]
9th November 2013 - 21:13

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I'm just using the bike for commuting Jack but that sounds like good advice and not to expensive. Many thanks to you both.

posted by joebee9870 [57 posts]
9th November 2013 - 21:16

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It was commuting that taught me how bad the Megaexo bearings are. Don't plan on a lifespan of any more than a couple of months unless they never, ever see rain.

By the way, check prices on complete chainsets before you buy rings for the current one. Frequently, the big Internet sellers knock out chainsets for less than a set of replacement rings.

My eyes prefer Celeste, my bum prefers titanium.

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posted by Jack Osbourne snr [304 posts]
10th November 2013 - 1:22

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