Fitting 105

[nylontoestraps]

Hi there,

I'm currently riding an older Viking San Marino, it was a hand me down and the bike that got me into cycling. I'm in the process of purchasing a new bike but as this bike holds sentimental value (belonged to my Father, first big rides etc) I'd like to keep it going and spruce it up a little. Is fitting a 105 group-set to this feasible ? Currently 18 speed Sora and still have plans to partake so century rides on this bike so the better shifting would be great.

Thanks in advance, NTS

 

[cyberknight]

Assuming it has Well set up gears the difference will be so minimal as to make it not worth doing unless you really want to for sentimental reasons also of you mean 11 speed 105 check if you're wheels are 9/10 or 11 speed as that could add to the cost

 

[slow scot]

You might find that the brakes have too short a drop to fit the Viking. And also that the Viking will only take older style nut and bolt brakes. The 105s will be Allen key fitting. I’ve had similar problems with older frames.

 

[wafter]

If it's a really old bike the axle spacing should be less than required to fit a modern groupset (5sp is 120mm, 6-7sp is typically 126mm and modern stuff from 8sp up is 130mm) however if it's already got Sora fitted then it seems this isn't an issue. Probably worth checking what the score is in this area though (has the frame been "cold set" - and if so is it all aligned correctly?).

If you have 130mm rear axle spacing the current 105 should go into the frame, however as cyberknight says the hub on the wheel might not be suitable for the 11sp 105 cassette (IIRC the spined section got a few mm deeper moving from 10-11sp; I have this "problem" on my Boardman if I ever want to go to 11sp) - so you might need a new rear hub / wheel too.

As slow scot says it's also worth checking the brakes - mountings on older bikes have a longer stud that's secured with a standard nut, while more modern stuff has a one larger hole on the non-caliper side of the fork / brake bridge to accommodate the modern recessed nuts that are now the standard. IIRC this standard started coming in during the early-mid '80s.

Other than that you'll probably be alright - as has been mentioned it's probably not a "financially sound" choice but those that are sentimentally driven rarely are; plus the R7000 groupset is very nice

 

[Ajax Bay]

Sora is the groupset which matches the bike (less than ten years old: when you say older, half the people on here think pre-Thatcher era). OP could fit a current expensive groupset eg 105 (with minimal shifting quality benefit) except:
1) 11sp cassette will not fit on current freehub (but could be changed - rear hub will be 130mm OLD).
2) 'Modern' 105 chainset will not fit on current ST cartridge BB so that'd need to be changed too.
3) Care to get the correct FD (band-on) to fit the seat tube OD.
3) Brakes (rim) = fine. STIs fine.
My recommendation for sprucing up would be a new set of good tyres and replace the brake blocks with Koolstop Salmon or similar.

 

[Cycleops]

Bit like putting a six speed gearbox into a Morris Minor but if you want to try why not? Main problem will be rear spacing as said.

 

[wafter]

Sora is the groupset which matches the bike (less than ten years old: when you say older, half the people on here think pre-Thatcher era). OP could fit a current expensive groupset eg 105 (with minimal shifting quality benefit) except:
1) 11sp cassette will not fit on current freehub (but could be changed - rear hub will be 130mm OLD).
2) 'Modern' 105 chainset will not fit on current ST cartridge BB so that'd need to be changed too.
3) Care to get the correct FD (band-on) to fit the seat tube OD.
3) Brakes (rim) = fine. STIs fine.
My recommendation for sprucing up would be a new set of good tyres and replace the brake blocks with Koolstop Salmon or similar.

Yeah, I was thinking '80s steel from the description.. in that case it sounds a lot more straightforward, but it also sounds like an ally bike which I'd be less inclined to throw a lot of money at. That said there's the sentimental factor and of course groupsets can always be transferred at a later date.

While I'd agree that fitting 105 doesn't make a lot of financial sense, I would suggest that it'll give a noticeable improvement in shifting quality (and probably braking) as my R7000 105 is noticeably better in this regard than my 4700 Tiagra; as objectively nice as the latter is. I'd imagine in turn that the Tiagra is nicer than Sora fitted to the OP's bike, so he should see a reasonable improvement if going to 105.

 

[Teamfixed]

In all honesty, being blunt maybe but what you have will work 99% as well as a groupset that is more expensive than 105. 105 is probably the sweet spot for working/price but the gains will be very small indeed and as mentioned there will be compatibility issues to be certain of first. The bike you describe will take you anywhere and as far as you wish to ride.
I would keep it as it is and enjoy it, it is of its time, 100% usable and reliable. If you are wanting to upgrade to a different bike then you would still have a very very serviceable, familiar 2nd bike/commuter/winter bike etc.

 

[jowwy]

Does he need to change the brake calipers....no mention of a braking issue in the OP.

When i hear groupset for me its normally crankset, derrauillers and shifters.......brakes are an after issue, cause there so many other braking options available outside of the range available

 

[si_c]

Fitting 105 is perfectly doable, but you will likely need to replace the wheels as mentioned above as an 11 speed cassette won't easily fit on a 9 speed wheel.

You'd get much better braking as well as slightly better shifting, the biggest thing you'll notice is that shifting has a lot lighter of an action on modern groupsets.

That being said, I think a better course of action might be to upgrade from the current Sora 3100 to R3000, it's also 9 speed, but it is a much more modern groupset and has the integrated cables at the front end that make the bike look much more modern as well as much improved shifting performance, it's almost as good as 105 in many respects.

 

[Ajax Bay]

an 11 speed cassette won't easily fit on a 9 speed wheel.
You'd get much better braking

An 11 speed cassette won't easily fit on a [8/9/10] speed [freehub].
Why do you think braking would be "much better"?

 

[si_c]

An 11 speed cassette won't easily fit on a [8/9/10] speed [freehub].
Why do you think braking would be "much better"?

You can use the R7000 11-34 cassette which does fit some 8/9/10 speed freehubs as it overhangs the freehub body at the back a bit, but it's very limiting.

The 105 calipers are much better than the Sora calipers, the feel of them is better, much more precise and there is more power through the brakes. I only know this as I moved from Sora to 105 on the same bike, so a direct comparison was possible. I think it's probably more down to how the lever pulls the cable than necessarily the calipers, but there is definitely a difference.

 

[nylontoestraps]

Really appreciate all the responses, many thanks. Aware that the 105 won't make a radical improvement to performance but having rented an Emonda with 105 the quality in shifting was noticeable. Also meant I was able to get down on the bars while still having access to shifters (Sora has a brake lever and a thumb button/clicker). It's going to be my occasional adventure bike, riding with slower friends and taking me with me when working away so looking to upgrade those bits that will make it a little smoother. Also not ready to take a punt on AliExpress !

 

[justinmg]

I presume you will change the chain rings also so BB also matches? A thinner 11 speed chain might stick on an older thicker chain ring

 

[bikingdad90]

You might find that the brakes have too short a drop to fit the Viking. And also that the Viking will only take older style nut and bolt brakes. The 105s will be Allen key fitting. I’ve had similar problems with older frames.

Can be solved with Tektro deep drop brakes. Currently on sale at Planet X for about £25.

It might be worth a punt on the Sensah empire Groupset, it’s reasonably priced and not as much to lose if it doesn’t work out?