Sora/Tiagra ugrade to 105 what's involved?

L'Enfer du Nord

I have a Giant SCR 3 2008-
http://www.giant-bicycles.com/en-GB/bikes/road/1399/29641/

With

SHIFTERS Shimano Sora 24 speed STI
FRONT MECH Shimano Sora
REAR MECH Shimano Tiagra
BRAKES Dual pivot long reach
BRAKE LEVER Shimano Sora STI

I have an other bike -a hybrid with shimano 105 derailers, for some strange reason I'm using the road bike less and less. So I've decided to upgrade the road bike to 105 (or possibly Ultegra),

Whats involved? Is it possible to simply upgrade the front and rear de-railers or do I have to upgrade the shifters/breaklever too? Are there any other issue with the upgrade? How much is the upgrade likely to cost?

Thanks

rflynnr

You don't mention the cranks, or the rear cassette or the chain. Are you planning on sticking with the existing drivetrain?

blorg

rflynnr wrote: »

You don't mention the cranks, or the rear cassette or the chain. Are you planning on sticking with the existing drivetrain?

You would have to change at least the chain and cassette out of those as the speeds are different. Cranks might still work OK, not sure.

L'Enfer du Nord

rflynnr wrote: »

You don't mention the cranks, or the rear cassette or the chain. Are you planning on sticking with the existing drivetrain?

CASSETTE SRAM PG850 12-26
CRANKS TruVativ Touro 3.2 30/39/50
CHAIN Shimano HG73

Cost is a major consideration, would consider switching to compact front group set.

DirkVoodoo

L'Enfer du Nord wrote: »

I have an other bike -a hybrid with shimano 105 derailers, for some strange reason I'm using the road bike less and less.

Just be sure that the reason you prefer the hybrid is because of the derailleurs and shifting performance and not due to anything else like comfort, geometry, etc.

I have to say that beside the clunky sora shifters, a well maintained sora geartrain performs just as well as ultegra for casual use.

blorg

As Dirk says, swapping the derailleurs over is unlikely to make a huge difference to anything.

L'Enfer du Nord

Thanks for the feed-back,

Indeed I think the fact that the hybrid has mud-guards could be part of the attraction this time of year.

I suppose I really have no issues with the Tiagra rear de-railer. I've had more issues with the front sora one. Would it be worth my while upgrading that to tiagra? i assume there is a tiagra front de-railer?

lescol

I have bikes with DA, tiagra and sora front shifters, no problems with any of them, I'm pretty sure I could change them around and not notice the difference. Check your derailleur set up, there's no reason you can't get a smooth gear change.