New bike or upgrade

Leave the current bike as is, buy yourself a different bike - go disc brake, cyclocross or maybe steel/titanium “adventure” bike. I do not see any point in upgrade of already very good wheels or groupset on Canyon bike, it is just not worth the investment. 

With a different bike you could go to roads/places you have not seen before, and that is the whole point :]

3 grand doesn't cut it.   Give the current one a makeover  and  save for a really special 42nd birthday present!

The problem is you won't get something a lot better for £3 grand. Anything that is a massive improvement will cost £8-£10 grand.

Give your bike a makeover: Strip back to the frame, replace all consumables, reassemble, ride it more. Or have the luxury of getting your LBS to do it for you.

Still sorry I sold my 'scruffy' Canyon...

Tricky!  Your Canyon has a good frame and if it looks tatty like you say you won't get much for it if you sell it.  Which suggests upgrade to me.  I think Canyon do their frames as either mechanical or electric so you might not be able to go electronic?  Unless you go for etap, which is great but is not a happy mix with Shimano cranks I have been told.  You really can't go wrong with either Ultegra or Dura-ace as a mechanical groupset and wheels around the £1k mark are good enough for anyone who isn't paid to ride, Reynolds perhaps?

Personally I think £3k is a real performance sweetspot for road bikes. So I can see it's tempting to go for a new bike however with a few exceptions the wheels won't be that great so you might need to budget for those as well.

So my suggestion would be Dura ace mechanical and new wheels and maybe renew contact points too, which would make it feel like a new bike and also go like stink!

With a budget of £3k and a 40th birthday coming up...would have to be a titanium something or other.  If you upgrade, what are you going to do with the savings?  I don't think an upgrade will give you much of a buzz, but a new bike?!  Oh boy...

Look for 'rider issued' on eBay too - someone was selling a nice Team Wiggins Pinarello for £3.5k a couple of weeks back...

If its comfy, upgrade components. Maybe go for electronic shifting plus new wheels? You say its looking tatty - custom paintjob would fix that. http://www.enigmabikes.com/paintworks/

A mate just upgraded to canyon disc bike, absolutely loves the new found confidence of braking.

I'd probably upgrade.

A new aero carbon wheelset and the new Ultegra groupset would make a massive difference.

I bought a Canyon Ultimate CF SLX Disc 8.0, I took the weight penalty with the discs and I certainly appreciate the more controlled braking - I also don't have to worry about wearing down carbon rims.

Despite this, if you buy some very good carbon specific rim brake pads, you shouldn't have an issue (providing you don't ride in the rain).

Lots of very valid points here, I'm currently in a similar situation.. I've made a list of things I want from a new bike (I can't have it all) and have then put pro's and con's against a shortlist. However as much as I look at my list, the pro's and the con's, my heart is seemingly still ruling... the desicion I'm currently leaning towards, is a very expensive winter bike which ticks less boxes than other cheaper models would. The decision is driving me a bit mad at the moment.

The canyon is a very good bike by all accounts, my mate has one and does very well with it, however he does complain every now and then about not being able to get low enough on it (quite a long headtube). 

Bear in mind that you 'could' by a raced team bike for half the cash they cost new.. bit of a risk I guess, but I took that risk and managed to get a top of the range bike for literally half price after seven months of racing, admittedly it needed a new bottom backet, cassette and rear hub wheel bearings.. but all told that cost me about a ton, I'm still saving nearer 3 grand.

My feeling would be upgrade.   That Canyon's a pretty good frame as far as I know and if you think it's brilliant then it obviously suits you.  If you're planning on spending that kind of money, or even something remotely near it, then with a good choice of wheels etc you could build a stonking bike around it.  The only thing that might change that is if you really want to go electronic since as mentioned above you might get a better deal for the complete bike.  Depends how strongly you feel about electronic.  I appreciate opinions vary on this but for 3k if it was me I'd stick with mechanical and upgrade wheels, chainset and as many other things as the budget will allow.

Change the brake and shifter cables. I bet it'll feel like a whole new bike.

What have you been doing to your bike that leaves it rough round the edges after only two years?  Are you riding 8 hours every day in atrocious conditions?!

I think the key question you need to ask yourself is what you are trying to improve:

• Aerodynamics (wheel upgrade can go a long way if you ride fast enough)
• Weight (again, wheels and various other bits and bobs can make a difference)
• Not comfortable on your bike or never quite gelled with it (could try a bike fit to see if that helps, otherwise, probably will be new bike time)
• Want to move from mechanical to electronic groupset (depending on the deal, you might find it more cost effective to buy a new bike, especially if you can sell the old one for a good price)
• Fancy something new (probably want to get new bike)

Whichever way you go, make sure your heart is fully behind that decision so that you don't always look back wishing you'd done something else.  There is a real joy in riding a bike that is really what your heart desired (within the boundaries of what you could afford).

"Will I notice a significant improvement in a replacement?"

Unlikely, IMVHO.

In my world £3k is a LOT of money. You could have some great bike trips/holidays with that. Which would be much more fun than blowing it all on another bike very much like your current (already excellent) one. It's not like you're looking to upgrade from a cheapie.

I'd buy some nice wheels, have it serviced then ride, ride, ride.

If your bike is really comfy for the type of riding you do, upgrade.

If you 'want' and 'need' a new bike, get one.