roborovski007

I would like to upgrade my current bike that came with 9 speed sora groupset to a 10 speed groupset, I'm wondering if the 10 speed cassette is compatible with my current wheelset ? Anyway, before this I had sent an email asking the bike manufacturer but they say it won't work and I need to change the hub in order to fit in 10 speed cassette. Trying to find more answers from you guys here

rhenning

It isn't worth the time and money to do what you are talking about unless your drive train is completely worn out. The lowest gear and the highest gear will remain the same and you just have couple of more redundant gears in between. Roger

Andrew R Stewart 

Depends on the hub. Many 9 speed free hub bodies will need the 1mm spacer to tightly fit the 10 speed cassette. As often is the case with this forum, we need more specific details before we can really help. Andy.

jimc101

All 9 speed freehubs (and 8 speed) are 10 speed compatible, from Shimano/SRAM, there was never a change in the spec of the freehub with this change in speed, going to 11 speed will require a specific freehub/hub, which with appropriate spacers is backwards compatible all the way down to 7 speed if you want.

Al1943

A 10-speed Shimano cassette will need a thin spacer at the back of the cassette to fit on a 9-speed Shimano compatible freehub. But all 10-speed Shimano cassettes sold new have the spacer included. It's my understanding that a 10-speed SRAM cassette does not need that spacer to fit a 9-speed Shimano freehub. To upgrade to 10-speed you will also need 10-speed Shimano compatible shifters and 10-speed chain.
There is a good argument that it would be better to not upgrade but instead just replace parts as they wear out.

FBinNY 

I suspect that one of the ironies of 10s vs. 9s which causes confusion. The freehub body requirements for 10s are actually narrower than those of 9s. While 10s cassettes are slightly wider (by less than 1mm) the innermost sprocket is moved inboard of the backstop on the body a bit, so the cassette is effectively narrower (re. the body) and calls for a spacer.

Drew Eckhardt 

It's worth at least $500 to get an 18 cog between the 17 and 19, although if also missing the 16 between 15 and 17 I'd spend more to get 11 in total.

OTOH, when running at least a 39 small or middle ring and 12-21, 13-23, or 14-25 without wanting a higher or lower gear 9 cogs are fine.

roborovski007

Thanks a lot for the reply guys, actually I have thinking of replace the whole groupset to 10 speed but now thinking of just replace parts that are worn out, anyway I'm looking for a new RD as the current one is bent, so now comes a new question, will a 10 speed RD works with my 9 speed sora group ?

alcjphil

There will be no problem using a "10 speed" derailleur with an otherwise 9 speed group, the actual indexing takes place in the shifter.

roborovski007

For example if let's say I would like to upgrade to Shimano 105 5700 10 speed group, I just need to replace the shifter, chain and cassette only, am I right ?

alcjphil

There are a couple of differences between the 105 5700 ten speed group and the previous 5600 group. The most obvious is the shift cables hidden under the bar tape. There is one other difference however. The 5700 group changed the pull ratio of the brake levers and callipers so that the levers pull more cable, thereby reducing mechanical advantage a bit. This means that if you change to 5700 shifters, braking will require more effort unless you change to the matching brake callipers as well. However, 10 speed 105 components are now out of production since the 5800 11 speed components were introduced last year