Upgrading from Sora Groupset

Since Sora is 8-speed and Tiagra/105/ultegra etc are 9-speed, a proper upgrade to any of the higher groups requires replacing a lot of parts.

If you are still keen though you could replace them in this order:
1. Rear derailleur - a 9-speed one will work fine with your sora shifters
2. Shifters, cassette and chain - officially you shouldn't use 9-speed stuff with an 8-speed crankset and f/der, but actually it'll work ok.
3. Crankset & front derailleur

You might find though that you can get a good price on, for example, a full 105 upgrade "kit" that includes all the bits you need to do it in one go.

Your alternative is to live with the Sora for a while until its really bothering you, then get a new bike. The difference between 8 and 9-speed isn't enough reason to upgrade, but if the performance of the Sora stuff is affecting your enjoyment of your cycling then its time to open your wallet...

Thanks so much for the concise and informative reply, nick. I'll jot all of these options down, and, after riding a while, if I find the Sora unacceptable, will discuss them with my dealer. Again, thanks so much.

dave

Quoted post said:

Originally posted by MidBunchLurker
Since Sora is 8-speed and Tiagra/105/ultegra etc are 9-speed, a proper upgrade to any of the higher groups requires replacing a lot of parts.

If you are still keen though you could replace them in this order:
1. Rear derailleur - a 9-speed one will work fine with your sora shifters
2. Shifters, cassette and chain - officially you shouldn't use 9-speed stuff with an 8-speed crankset and f/der, but actually it'll work ok.
3. Crankset & front derailleur

You might find though that you can get a good price on, for example, a full 105 upgrade "kit" that includes all the bits you need to do it in one go.

Your alternative is to live with the Sora for a while until its really bothering you, then get a new bike. The difference between 8 and 9-speed isn't enough reason to upgrade, but if the performance of the Sora stuff is affecting your enjoyment of your cycling then its time to open your wallet...

caintuck

I bought a Trek with a mostly Sora groupset a couple of years ago myself. My impressions are 50/50. I have also been toying with the idea of a 105 upgrade, but I can't justify it given the rest of the components on my soon to be retired ride. Things might be different with the SL tubing on your frame though. Personally, I would look at the fork first. You could definitely find a smoother ride than aluminum will provide.

Sora shifters are designed to be more easily shifted from the brake towers instead of the drops. This, I believe, is desireable for cyclocross style riding. The sora rear derailleur is also designed to accomodate up to a 11-28, 8 speed mtb cassette where a 105 is supposed to be limited to a 12-27 road cassette. Shifting on the rear has always been crisp for me.

I don't know about the Bontrager crankset, but I think the Sora crankset (and the CPI crankset on my bike) uses steel chainrings. >>double checked, only the inner<< Although they're heavy, they will likely outlast the alloy rings on a 105 crankset. >>My 105 rings showed signs of wear after ~1000 miles.<< Many 8 speed chains are also stronger and will outlast 9 speed chains under most circumstances. Unlike the rear, shifting on the front has left me unimpressed.

Finally, watch the bottom bracket. The cheap POS that game with my Trek was worn out after just 2000 miles. Everything else is still working like like it was new after 3500.

cachehiker

Thanks cashehiker. Yeah, everything I've read mentions that shifting from the drops is a real pain with Sora.

I hadn't thought about changing the fork. I'll give that a hard look after I've ridden the thing for a while.

Everything you wrote is going in my notebook for future reference. Thanks.

Quoted post said:

Originally posted by cachehiker
caintuck

I bought a Trek with a mostly Sora groupset a couple of years ago myself. My impressions are 50/50. I have also been toying with the idea of a 105 upgrade, but I can't justify it given the rest of the components on my soon to be retired ride. Things might be different with the SL tubing on your frame though. Personally, I would look at the fork first. You could definitely find a smoother ride than aluminum will provide.

Sora shifters are designed to be more easily shifted from the brake towers instead of the drops. This, I believe, is desireable for cyclocross style riding. The sora rear derailleur is also designed to accomodate up to a 11-28, 8 speed mtb cassette where a 105 is supposed to be limited to a 12-27 road cassette. Shifting on the rear has always been crisp for me.

I don't know about the Bontrager crankset, but I think the Sora crankset (and the CPI crankset on my bike) uses steel chainrings. >>double checked, only the inner<< Although they're heavy, they will likely outlast the alloy rings on a 105 crankset. >>My 105 rings showed signs of wear after ~1000 miles.<< Many 8 speed chains are also stronger and will outlast 9 speed chains under most circumstances. Unlike the rear, shifting on the front has left me unimpressed.

Finally, watch the bottom bracket. The cheap POS that game with my Trek was worn out after just 2000 miles. Everything else is still working like like it was new after 3500.

cachehiker