Changing to a compact double - Decathlon sport 7.1

Mikey1280

Hello,
I want to change to a compact double on my decathlon (the cheap one on offer a few years back). I'm a bit confused about removing the crankset and installing a new one. What tools do I need to remove the crankset (it looks like it has a large allen head bolt)? Are cranksets compatible with all bottom brackets? How do I find out what type of bottom bracket I have?

Thanks

Mike

topdude

No offence but i suggest you take the bike to your LBS and get their advice. Several special tools and a bit of bike knowlege will be required

Wappygixer

These were fitted with a square taper bottom bracket so it you want to keep the same set up then stick with square taper, there is nothing wrong with it and it works well.
You will need an 8mm allen key to remove the crank bolts.You will also need a crank puller or extractor to pull off the cranks.
As the 7.1 was fitted with a 39/52 (if my memory serves me right) you will also need a new front mech as the ones came fitted to these wont cope with the 16 tooth difference in the chain rings.
Campag can still be found knocking around in square taper compacts and a Camapg front mech is cheap enough these days, just make sure its suitable for a compact.

Mikey1280

topdude wrote:

No offence but i suggest you take the bike to your LBS and get their advice. Several special tools and a bit of bike knowlege will be required

None taken. I admit I came across pretty clueless in my original post. I have lots of free time and would rather not pay other people to do jobs on my bike.
After a bit of reading on the park tools site I realise that I'll need a crank extractor suitable for square taper cranks and another tool to remove the bottom bracket.

I was thinking of getting this FSA chainset on offer from planet x here. It says it has an english threaded bottom bracket 68mm width, is this standard for road bikes?

Wappygixer; how do I know if a front mech is suitable for compacts?

Wappygixer

Most road bikes have a 68mm bottom bracket and the 7.1's do too, its also english thread.
You will also need another tool to fit the new bottom bracket too.
As for a front mech I'd probably go for a SRAM Rival as they seem to work a bit better than Shimano compacts ime.
Most front mechs are now compatible with doubles and compacts especially the Campag and SRAM ones.
I have a SRAM Rival fitted to mt Cyclocross and it runs a compact set up and it shifts fine, the rest of the drive chain is Shimano 105.

Mikey1280

Ok thanks for that Wg, I see that the FSA chainset has a megaexo bottom bracket which according to wikipedia means I should be able to use a hollowtech II bottom bracket tool, have you any experience with these integrated drivearm bottom brackets?

Wappygixer

I have a howwlow tech II bottom bracket on my mtb.
Some are a bit rubbish to be honest, I n kow early Shimano ones didm't last the distance too well.You now have the likes of Chris king and Hope making them now which are superb and last ages.
I use a Hope botton bracket and its still silky smooth.It would cost more than your complete chainset though but them so will most replacements.

Mikey1280

Having seen the cost of replacement mega exo bottom brackets I have had a rethink and perhaps I would be better off getting a campag chainset such as this one? Does traditional bottom bracket mean a square taper one?

One more question, there are no issues with it being '10speed' and me having 8spd right?

Wappygixer

Traditional does mean square taper but should really be mounted to a Campag square taper bottom bracket as the taper is slightly different to a Shimano standard but in reality it should work ok,
10 speed will work ok with an 8 speed set up, its the other way around that can cause issues.