Sora to Ultegra Cranks

[Bristolian]

Hi folks, I wonder if anyone can help me out with some advice?

My 2010 Specialized Allez has a 3x9 Shimano Sora groupset which is working very well, despite its age - if only I could say the same about me

I'm a bit of a techie geek and I have been toying with the idea of adding a power meter but the prices are pretty high for something that I don't really need (but do want). Recently, I was offered a dual sided Ultegra power meter at a very "favourable" price but that comes with a 2x crank and chain rings. I know that I can adjust my Sora front derailleur to only work with the outer and middle chain rings of my current set-up but I don't know if that means they would work with the Ultegra 2x chain rings - I'm unsure if the throw between the two rings on the Ultegra is the same as between the outer and middle on the Sora - anyone?

A supplemental question; the Ultegra chainrings above are from an 11-speed bike so does that give me an issue with my 9-speed chain?

Thanks in advance

 

[fossyant]

Throw will be similar, and the chainrings will work. Front mech should be OK with some fettling. You will have an extra click in the shifter though, thats best set from the smallest chainring so you get one click up before the limit stops, not the other way as you'll get a slack cable.

 

[I like Skol]

Might get some chain rubbing on the chainrings as 9 speed chain is wider than 11spd and I think the chainring spacing will be different to accommodate this?

 

[Jameshow]

Is the Sora a ht2 BB, or square taper?
If ST then you'll need a new BB which wouldn't be a bad idea anyway.

 

[bobzmyunkle]

2010 triple sora chainset also weighs about 3 tonnes(slight exaggeration). I replaced one with a Spa triple and was amazed at the weight difference.
Weight isn't everything, of course.

 

[Cycleops]

Your Allez triple looks like it has a ST BB and the Ultegra will have Hollowtech I imagine so you'll need a HT BB which is about £20 I think and is a direct swap.

 

[Bristolian]

Throw will be similar, and the chainrings will work. Front mech should be OK with some fettling. You will have an extra click in the shifter though, thats best set from the smallest chainring so you get one click up before the limit stops, not the other way as you'll get a slack cable.

Many thanks for the reply. I hadn't considered which way round to limit the derailleur so that's good thinking 👍

 

[Bristolian]

Might get some chain rubbing on the chainrings as 9 speed chain is wider than 11spd and I think the chainring spacing will be different to accommodate this?

Yes, I was wondering about that too but I don't think the difference between 9 & 11 speed chains is too big. I also wonder whether the chain will tend to slide sideways on the chainrings?

Edit: Sorry, I forgot to say thanks for your reply ... my bad ☹️

 

[Bristolian]

Is the Sora a ht2 BB, or square taper?
If ST then you'll need a new BB which wouldn't be a bad idea anyway.

Many thanks for your reply. The bottom bracket is HT2 - I took it out on Monday to give me better access for cleaning the frame. The BB is actually in very good condition so I don't think it will need to be changed.

 

[Bristolian]

2010 triple sora chainset also weighs about 3 tonnes(slight exaggeration). I replaced one with a Spa triple and was amazed at the weight difference.
Weight isn't everything, of course.

Many thanks for your reply. Yes, it is pretty heavy but compared to me (115kg ) it's also pretty insignificant

 

[fossyant]

If picking up a second hand chainset, check the condition, as Ultegra rings aren't cheap.

 

[Bristolian]

Your Allez triple looks like it has a ST BB and the Ultegra will have Hollowtech I imagine so you'll need a HT BB which is about £20 I think and is a direct swap.

Many thanks for your reply. I'm lucky that the BB is ST2 and is in good condition so that's one less thing to worry about

 

[fossyant]

Other question, what are you hoping to gain with a power meter. One reason I like my Garmin is I ignore it when riding unless it's navigation. You just get on with enjoying the ride.

 

[Bristolian]

If picking up a second hand chainset, check the condition, as Ultegra rings aren't cheap.

The Ultegra chainset is like new - it has only done about 200 miles. The person is only selling it because he doesn't get on with the cranks, which are shorter than he is used to.

 

[Bristolian]

Other question, what are you hoping to gain with a power meter. One reason I like my Garmin is I ignore it when riding unless it's navigation. You just get on with enjoying the ride.

TBH, I'm not sure I'll gain anything. As I said in my OP I don't need it but I do want it. In photography terms we call it GAS (Gear Acquisition Syndrome) - always wanting to have something a little bit better. Buying a Garmin was the same; want rather than need, and like you I pretty much ignore it whilst out riding but it's nice to be able to look at the ride stats afterwards and see if I'm improving rather than relying just on whether I feel like I am (or not). The power readings will just be another metric but will also (hopefully) validate the "estimated" power figures that the Garmin comes up with now.