Crankset question

Hi guys
Im new to these forums so ill post as much info as i can.
I have a Tiagra crankset on my CAAD4 that i want to upgrade and I am after some advice on what would be a good upgrade for this crankset ?
The guy who had the bike before me said he put at 27/12 cassette on it. The front derailluer is a FD-4400 and rear derailleur is a 105.
Ideally id like to upgrade to a 105 or better ?
I'm happy to provide more information and model numbers if required. Just might little a little nudge to find where they are.
Thanks for your help
Im new to these forums so ill post as much info as i can.
I have a Tiagra crankset on my CAAD4 that i want to upgrade and I am after some advice on what would be a good upgrade for this crankset ?
The guy who had the bike before me said he put at 27/12 cassette on it. The front derailluer is a FD-4400 and rear derailleur is a 105.
Ideally id like to upgrade to a 105 or better ?
I'm happy to provide more information and model numbers if required. Just might little a little nudge to find where they are.

Thanks for your help
0
Posts
Crankset is Tiagra 170 FC-4400/4403 - Looking for a good replacement for this ?
Chainrings are 9 speed 39/52 - Does a new crank set come with chain rings ?
Rear mech is a RD-5500 and front mech is a FD-4400
Any recommendations on upgrades for this crank set ?
Is it possible to keep to a good 9 speed or is everything 10 speed these days ?
You can get 39/52, that is a standard double.
You can also get 34/50, which is a compact, but this would need the FD moving. It makes it easier up hills (if you struggle with that).
Very difficult to get 9 speed but 10 speed cranksets will work fine.
In summary - if it works wait till it wears out, then get a new one.
Bottom bracket bearings wear out, as do the chainrings, but either can be replaced without buying a new crankset. The other bits that wear out are the chain and the cassette, and periodically the cables will need replacing.
As mentioned above, if it's all working, it's an expensive and unneccessary job to replace the whole lot. If however you have the cash and want new, shiny matched parts, go for it!
As for the transmission as a whole, this is often a waste of money as well. Derailleurs, cranks and cogs are very simple things and will only vary so much. As they get more expensive you should get slightly smoother performance (though that will depend on how well the bike is maintained!) and a little lighter. It will cost you a lot of money in relative terms but it won't make you any faster (though this is generally the case with equipment upgrades), and - though this is not the case all the time by any means - the frame and wheels may only be as good as the parts that are on it. Putting expensive bits on a cheap frame with cheap wheels is a bit pointless.
Fixed TT 2015-2016
The only exception would be to more to asymmetrical which I did as an upgrade which was cheaper to change the whole crankset as the old one went on the winter bike in my case.