Replacing front and rear mechs after crash

[scotthunter]

After crashing my bike at the weekend and damaging the front and rear derailleurs, I've decided to replace like for like. I need to order the parts so I can get my bike shop to repair my bike.

Can you advise what I need to get as there are different types of Ultegra R8000 front and rear mech.

Do I need a short cage or medium cage rear mech, and for the front mech do I need braze-on, 28.6mm/31.8mm or 34.9mm?

It's an 11 speed semi-compact Giant TCR Advanced Pro 1 (2018).

Thank you!

 

[Joffey]

From a look at the photos online it looks like you need a med cage rear and a braze on front.

I would compare your parts with pics online before spending money or even taking it to the LBS who may price match the online parts - then you know you are getting the right bits. They will probably fit them for £25ish too.

 

[raleighnut]

^^^^^^^ Wot e sed.

 

[gbb]

Id probably get a rear hanger as well.
If you've damaged the derailleur, you've quite likely done the hanger too.

 

[Ajax Bay]

Do I need a short cage or medium cage rear mech, and for the front mech do I need braze-on, 28.6mm/31.8mm or 34.9mm?
It's an 11 speed semi-compact Giant TCR Advanced Pro 1 (2018).

If you don't "know" this stuff (eg difference between braze-on and band-on FD), I second/third the advice to get clear advice from your LBS. Any premium will be well spent on the assurance that you're getting the correct parts first time (and can get back riding your nice bike without delay. They can also give you a considered opinion on the hanger and get one for you.

 

[I like Skol]

If you don't "know" this stuff (eg difference between braze-on and band-on FD), I second/third the advice to get clear advice from your LBS to source the parts and fix it.

THIS^^^^^

If you can fix it yourself, get your own bits. If you can't even identify the correct parts with certainty and then need someone else to fit them then at least have the decency to give them the full job. They have the right to make a living from their knowledge, skills, experience and training without someone that hasn't a clue trying to skim part of their wages out of the job!

 

[Milkfloat]

Are you sure they are both damaged? IMO it takes quite a lot to damage both components and if you really have, perhaps you have bigger issues with the bike.

 

[scotthunter]

THIS^^^^^

If you can fix it yourself, get your own bits. If you can't even identify the correct parts with certainty and then need someone else to fit them then at least have the decency to give them the full job. They have the right to make a living from their knowledge, skills, experience and training without someone that hasn't a clue trying to skim part of their wages out of the job!

Brought the bike from them 4 weeks ago so they have had good custom from me, and was due a free first service anyway. It's not like I'm walking into a new bike store with a bunch of components saying fit this. Obviously people in my unfortunate situation are going to be hard up on cash having just shelled out on a new bike.

 

[scotthunter]

Are you sure they are both damaged? IMO it takes quite a lot to damage both components and if you really have, perhaps you have bigger issues with the bike.

Well the bike landed on the road on its side when I came off so scratched the rear mech, right pedal and right corner of the handlebar. The chain came off and I noticed both the front and rear mech were a bit bent. Otherwise the frame and wheels look fine.

 

[si_c]

Well the bike landed on the road on its side when I came off so scratched the rear mech, right pedal and right corner of the handlebar. The chain came off and I noticed both the front and rear mech were a bit bent. Otherwise the frame and wheels look fine.

I'd suggest posting photos, the front mech is rarely damaged, sometimes it can be twisted out of position, but that is fixable. The rear derailleur if the impact is pretty hard can sometimes damage the cage, but depending on how bad it is, this can often be fixed by bending it back into place. Also you'll need to check the hanger as mentioned above.

If you take a photo side on and from the rear of both derailleurs then someone here is likely to be able to offer advice.

 

[I like Skol]

Brought the bike from them 4 weeks ago so they have had good custom from me, and was due a free first service anyway. It's not like I'm walking into a new bike store with a bunch of components saying fit this. Obviously people in my unfortunate situation are going to be hard up on cash having just shelled out on a new bike.

I would still be asking them to quote for parts too. If you need to keep a good relationship with them (and it sounds like you do) then keep them on board by giving them the business. It works both ways, they will treat you as a good customer and maybe give preferential pricing if you ask nicely, and you need to be able to trust them not to rip you off on parts and servicing. How much are you really hoping to save by supplying your own parts?

 

[Will Spin]

As above, it's quite hard to damage the mechs. It's most likely that the rear derailleur hanger has bent (often happens in a crash or even if you just drop the bike). In a lot of cases it can be bent back into line but it's best to get the bikeshop to do this if you don't have an alignment tool. Even if you need a replacement hanger it's still cheaper than a whole new mech. Similarly to front mech may have just moved on its mount, so it's worth a check to see if it can be realigned.

 

[Ajax Bay]

If you do replace the derailleurs, don't throw away the 'damaged' ones (or ask your LBS to return them to you after they've fitted the new ones).

 

[vickster]

Carbon frame? Get the LBS to give it the once over

My LBS will happily fit parts sourced elsewhere but charge a surcharge on top of the fitting fee which is fair enough (think it’s an extra fiver) especially as parts can be rather cheaper online (they charge RRP normally)