Groupset Upgrade

[Ducky]

I have a Cannondale CAAD 8 Tiagra 2011 9 speed and I would like to upgrade the groupset. Probably to a 105.

First question: the bottom bracket is an FSA Mega Exo BB-4000 - does this mean I can use the standard Shimano Bottom Bracket that comes with the 105 groupset? I think newer CAAD8 have a BB30 bottom bracket so I would need to get FSA chain rings too - I would rather just stick with the standard Shimano kit if possible.

Second question: given that it is currently a 9 speed, will there be any issues fitting an 10 (Tiagra) or 11 (105) speed cassette on it?

I'm a bit of a novice at this so just want to be sure it will all work!

Ta!

[hamster]

11 speed requires a different hub, so you have the choice of up to 10.

Personally I would upgrade the wheels first rather than the groupset. The difference between 105 and Tiagra is a few grams - and I bet you wouldn't be able to tell the difference in the dark. If the shifting is a bit off, give it all a good clean and fit new cables and (especially) outers.

[Ducky]

Thanks for the advice. I'll make sure I don't go for anything over 10 speed. I guess that makes my decision on Tiagra vs 105!

I upgraded the wheels when I got it so no need there. I need to replace chain (stretched) and cassette, and the front derailleur is slightly bent - hence why I thought I might as well upgrade the whole groupset.

[TrevA]

You can still get 10 speed 105, but by restricting yourself to 10 speed you've got built in obsolescence. Nearly all new wheels, even cheap ones, come with 11 speed hubs nowadays.

I've got 10 speed Tiagra and it's not brilliant to be honest. The gears are very hard to keep well adjusted and rather clunky.

[tim_f]

re "I upgraded the wheels when I got it so no need there"

If you have a spacer behind your 9 speed cassette on your existing wheel, then is likely that you can fit a 11 speed cassette, if you do not have a spacer it is likely that you can not fit a 11 speed cassette to the hub.

This thread https://forum.cyclinguk.org/viewtopic.php?t=78016 indicates that the BB on a 2008 CAAD 11 has a threaded bottom bracket.

Have a look at your bike and see if the bearings crew in to either side of the frame externally - if they do then a standard Shimano BB should fit.

The 'new' 4700 Series Tiagra 10 speed (with gear cables hidden) is different to the superseded 4600 series Tiaggra.

It is repudiated to be similar to 11 similar to 11 speed 105, but with one less cog - but I do not have personal experience. I recall reading they have changed the cable pull.

[Brucey]

...I've got 10 speed Tiagra and it's not brilliant to be honest. The gears are very hard to keep well adjusted and rather clunky.

Tiagra 10s can be either 4600 series or 4700 series. They are not at all similar to one another (as noted in another post).In fact it would be fairer to say that they are completely different groupsets that happen to share a name and nothing else.

Re the OP's bike: If it were my bike I'd get a new chain and cassette, straighten out the front mech if it really needs it, or replace it, and carry on with the bike as it is. A new groupset is an expensive solution to a problem that you probably don't really have, and whilst anything is possible, it might create more problems than it 'solves'....

BTW 'upgrade' wheels in 2011 could still have been 8/9/10s compatible only. And if you have worn out your chain and cassette with 9s, it may be worth contemplating how long 10s or 11s stuff is going to last by comparison; 'less long than 9s' might be the conclusion...

cheers

[TrevA]

Point taken. Mine is 4600, which having been superseded, is probably no longer available. Hopefully 4700 is better.

I've got 9 speed Tiagra on my tourer and my old winter bike, and they've both been faultless, as is the 9 speed Tiagra on my wife's Dolce.

I've not noticed 10 speed chains and cassettes lasting any less long than 9 speed, but it's probably not a fair comparison as they are on my summer and winter bikes respectively. Generally, stuff doesn't last as long in winter.

[tim_f]

I think Brucey , as ever is very wise.

Replacing just the worn out components with 9 speed Sora 3000 components will get your bike back to 'as new' at very little expense.

I think 9 speed Sora 3000 is very similar to the previous 9 speed Tiagra so should not be regarded as a downgrade.

[Ducky]

Thanks for the input guys.

I have looked and I do have a spacer and I think the BB is fine to be compatible.

However......you're both probably right and I would be better just to replace the chain and cassette. I have bent the derailleur back and it seems to be OK. I'll keep a close eye on it and get a Sora front derailleur if needed. Other than the bent derailleur, I'm pretty happy with performance.

[cycleruk]

My latest gripe with the new current Shimano Tiagra and 105 (+ Ultegra etc) is the chainrings. They are all specially shaped that a standard replacement is not viable. Besides I think they are ugly
I have just ordered a 105 5703 chainset and will stick with that as I can get replacement rings easily.

[Des49]

I recently put a 105 11sp groupset on a 2nd hand Specialized Allez, it is quite remarkable. Beautiful gear changes and the brakes have great power and feel. (But I am generally more used to riding components from 2 to 3 decades ago). The price of these groupsets seems to have dropped a lot if you shop around or wait for a deal to come up.

The chainrings on the new 5800 chainset do seem hard to come by, but I have a 39 inner which is swapped around with a 34 depending on who is using the bike. Outer rings seems rather pricey, but inners pretty reasonable. It is brilliant that these newer chainset designs allow such a wide gear range to be easily fitted.

I noticed that TA appear to now produce chainrings for these Shimano designs, but availabilty seems minimal.

[Ducky]

Thanks everyone for your input - much appreciated!

I've decided to go for the simple option and just replace the chain & cassette and keep an eye on the front mech for now.