[philelson74]

I have a Giant Defy with triple shifters for a FSA Tempo triple crankset. I had to recently change the FD to a Shimano Claris one as my one had failed. I now want to change the crankset from the current 52/42/30 one.

I found a Claris one on Evans Cycles at 50/39/30 and asked them the question could I swap it out, the answer I got in reply was NO. Can anyone tell me why as I don’t fully understand why this can’t be done. I intend to change the shifters to newer triple ones shortly and could also change the RD if necessary.

Thanks in advance from a newbie.

Topic

[philelson74]

Thanks Woldsman

Thanks Woldsman

You make some very good points and definitely something I had thought about. I need to give this all more thought really. 

A whole new group set is very expensive in one go which is why I was just considering upgrading my current 8 speed offering with newer versions for now to liven the bike up a bit but that way I can do it bit by bit. 

The FD was knackered anyway, no longer shifting at all so for £20 was worth replacing it for the 8 speed Claris option. A new cassette and chain should set me back another £30 and about £25-30 if I want to replace the RD. Shifters on the other hand are really hard to come by it would seem and expensive as you rightly say. 

I was also considering stripping the whole bike down, sanding it down and respraying it as a project. I know people will say why not buy a new bike but I like the bike and time to do it isn’t a problem.
 

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[Woldsman]

Hang on a minute, Phil…

Hang on a minute, Phil…

I know you’ve had the expense of the Claris front derailleur (max £25?), but if you’re thinking of replacing the shifters (why?), chainset (for a lower top gear?) and rear derailleur (bit knackered?) could I suggest you consider using this as an opportunity for upgrading a bit?  

There are 10-speed options (some years ago on my triple road bike I went from 9-speed Sora to a 10-speed 105 triple), but 10-speed triple options have narrowed these days: they are expensive if available at all.  

People generally opt for a triple to give lower gears (amongst other other desirable things), and current 9-speed Sora also offers a greater range of cassettes, again with the lower gear option of max 34T sprockets.  

You’d need a new cassette and chain, obviously, but these are consumable items and you may be close to renewal in any case (and the Shimano BB-R60 Ultegra 6800 Bottom Bracket is about the same price as your new front mech).  Of course, the more stuff you buy to stick on an old bike the nearer you get to the price of a new bike, but hey ho…

So, if you’re intent on upgrading, whatever you decide to do I would recommend sourcing the replacement components at the same time if funds allow.  Shifters and chainsets in particular are relatively expensive investments – and Sora/Claris quality may well last the remaining lifespan of your current bike.  But availabilty of some parts at the moment is volatile and you don’t want to be stranded with pricey gear that isn’t compatible with what’s out there in the near future. 

Just a thought.  Best wishes. 

[kil0ran]

You’ll need a crank extractor
You’ll need a crank extractor and square taper splined cup remover if you don’t have those already. Spray the Tempo BB liberally with release oil and go slow and easy, particularly if they’re plastic cups. Very easy to strip the splines getting them out, particularly if it’s the original factory fit BB. If it all goes well though it’s a quick job, 1 hour and you should be done. As someone else posted, get a new chain rather than shorten the old one. 8-speed chains aren’t expensive, and get a quick link whilst you’re at it.

[philelson74]

Thanks Drinfinity, much

Thanks Drinfinity, much appreciated. I can do all that, recently changed the BB onmy wife’s Specialised so I have all the tools so not too much of a big deal as you rightly say.

I guess it was more a question of the tooth change sizing and as long as I go for something very similar to my current chainset spec, I should be ok. I’m happy to change the BB whatever chainset I acquire.

 

 

[Drinfinity]

The FSA Tempo is a square

The FSA Tempo is a square taper fitting as far as I can tell.  The current Claris is Hollowtech.

This means you would need to change your bottom bracket for a matching one. Not a big deal for a bike shop, and easy enough for the home mechanic with the right tools (simple and cheap).

If you are replacing chainrings I would usually replace the chain at the same time. Old chain on new rings is a nasty combination.

Or you could find an alternative square taper triple (looks like Wiggle are ahead of me on this!)

[philelson74]

Thank you Kil0ran, very much

Thank you Kil0ran, very much appreciated.  That is also what I thought but wanted an opinion from someone far more knowledgeable than myself. Surely the worst case scenario is that I need to remove a couple of chain links. Like I say, the from derailleur is now a Claris anyway and the crankset in question is also Claris.

[kil0ran]

Assuming you’ve got triple

Assuming you’ve got triple shifters a triple crankset is a triple crankset is a triple crankset, I can’t think why Evans would think it isn’t possible.

In general front mech and crankset compatibility is pretty simple – as long as the amount of cable pulled by the shifter matches how far the front mech is moved. I’ve got Tiagra shifters, a 105 front mech, and a 105 chainset on my bike for example. Up front the fact that 105 is a 11-speed makes no difference. 

The only possible explanation is that the front mech can’t be dropped low enough to accommodate the 2-tooth drop in the chainring but that seems highly unlikely. It is something that you see on high-end race frames with beefy seat tubes but I doubt very much it’s the case on a Defy Triple.

[Author]

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