Newbie Cassette Question

For discussions about bikes and equipment.
Gazelain
Posts: 15
Joined: 13 Aug 2019, 11:06pm

Newbie Cassette Question

Postby Gazelain » 13 Aug 2019, 11:16pm

Hi all,

New to the forum and new to road cycling so I apologise in advance if this question is covering old ground.

I have a boardman 8.6slr with the Shimano Claris group set with an 8 speed 11-28 cassette. A friend of mine is upgrading his wheels and asked if I wanted his old ones off his Scott Addict which has the 105 group set 11 speed 11-32 cassette on it.

First question, would I get away with switching the wheels with only replacing the rear derailleur for the 105, or is there more work involved.

Second question, could I just buy a new 8 speed 11-32 cassette and fit that to the new wheel.

Hope I've made this clear enough.

Thanks in advance.

Samuel D
Posts: 2752
Joined: 8 Mar 2015, 11:05pm
Location: Paris

Re: Newbie Cassette Question

Postby Samuel D » 14 Aug 2019, 8:34am

Gazelain wrote:First question, would I get away with switching the wheels with only replacing the rear derailleur for the 105, or is there more work involved.

There is more work involved, because you’d also need a new STI shifter/brake lever that pulls the right amount of cable per shift and has 11 gear positions. And you’d likely want two, so that left and right match. New 11-speed STI shifters are expensive. And if you replace the left one too, you’d likely need a new front derailleur as well. You’ll need new cables and housings, which means you’ll also need new bar tape. It becomes a big job.

Gazelain wrote:Second question, could I just buy a new 8 speed 11-32 cassette and fit that to the new wheel.

Yes. You could also use your existing 8-speed cassette or one like it. Or any other 8-speed cassette. In the future with another bicycle, you could use any 8-, 9-, 10-, or 11-speed cassette on the wheel.

However, since 8-speed cassettes are a little narrower than 11-speed ones, you’ll need a thin, 1.85 mm spacer to take up the slack. This spacer is normally included with 11-speed wheels or hubs. Ask your friend if he has it. If not, they can be readily purchased.

thelawnet
Posts: 2130
Joined: 27 Aug 2010, 12:56am

Re: Newbie Cassette Question

Postby thelawnet » 14 Aug 2019, 9:55am

You would have to check the specifics but it looks like the Scott has a Syncros RP2.0 wheelset with 18 spokes at the front and 24 at the back. Apparently these are rebranded DT Swiss and weigh only 1.54kg. Any 'upgrade' from these is a bit doubtful but that's a matter for your friend.

Your existing wheels are heavier, 32 spokes back and front, and hence more durable. If you have nice smooth tarmac and aren't too heavy yourself, the Scott wheels would be quite good.

I'd be tempted however to keep both sets of wheels and buy a new 8 speed cassette for the 11-speed wheel, rather than attempt to 'upgrade'. That way you can have two sets of wheels for different conditions, with different tyres.

Your bike is a fair bit heavier than the Scott, for what it's worth the differences between Claris and 105 is something like:

* brifters: all but identical, including weight ; if you go up to Ultegra (which is cross-compatible) you get carbon fibre brake levers, which can be nice in the winter. Possibly there is a jump in thye quality of the internals between one or more of the levels, but that's not entirely clear
* rear derailleur - 105 has better jockey wheels and is likely to stand up to weather a bit better. Ultegra is a bit better. Weight differences are almost irrelevant
* cassette - they weigh and work much the same
* chain - it's narrower for 11 speed and shaves a few grams off

Also your bike has an FSA crankset, which is lighter than the Claris one and a bit heavier than 105, though lighter than some bikes sold with 105, which have a non-series crankset.

Your brakes are 57mm reach Tektro ones, which are not a direct match for any Shimano part, but they should work with both 105 & Claris brifters, giving better tyre clearance than some of Shimano's offerings.

The wheels for free are a deal but I wouldn't bother upgrading the other stuff - your bike will always be a cheapo and relatively heavy (not that this is a big issue - the 8kg Scott is at best 2% faster up a steep hill (assuming you aren't a four-stone apology)), and spending lots of money on new components would save maybe 200 grams which is irrelevant unless you are an obsessive or very gullible, or both.

Gazelain
Posts: 15
Joined: 13 Aug 2019, 11:06pm

Re: Newbie Cassette Question

Postby Gazelain » 14 Aug 2019, 12:15pm

WOW - guys, thank you so much. that's really helped me.

i think i will take the wheels off my friend but keep the 8 speed cassette, perhaps go to the 11-32 as i struggle a bit on the hills at the moment so could do with that little extra gearing. therefore, I would need to get the 1.8mm spacer as mentioned by Samuel D.

the Boardman is an OK bike, but certainly for a beginner. I had a go on my mates Scott, it's a fair bit better which I could tell fairly quickly - I will look to upgrade it at some point in the future but will serve me well in the meantime.

having said that, i've signed up for the 100 Ride London 2020 - so might fancy the upgrade before that :) lol.

thank you again for your responses - they're very much appreciated.

slowster
Posts: 805
Joined: 7 Jul 2017, 10:37am

Re: Newbie Cassette Question

Postby slowster » 14 Aug 2019, 1:18pm

Gazelain wrote:could I just buy a new 8 speed 11-32 cassette and fit that to the new wheel.

Gazelain wrote:perhaps go to the 11-32 as i struggle a bit on the hills at the moment so could do with that little extra gearing

An 8 speed 11-32 cassette has bigger gaps than your current 11-28 cassette. There's a good chance that you would find the 3 tooth jumps between the 15, 18 and 21 tooth sprockets to be too big, especially when riding hard/fast.

It would probably be better to put the money you would spend on an 8 speed 11-32 cassette towards the cost of reducing your gears by changing the chainset instead. The 50 tooth outer chainring is probably too large: you would probably only use it with the 11 tooth sprocket if you were sprinting downhill in a race. Replacing the 50/34 chainset with something like 46/30 will still give a high enough top gear, some much lower gears AND avoid excessively large gaps between your gears.

You can see the differences illustrated visually in these links:

Comparison of 11-28 vs 11-32 8 speed cassettes with 50/34 chainset

Comparison of 50/34 vs 46/30 chainsets with 11-28 cassette

In fact, a chainset even smaller than 46/30 might be better still: even 46 x 11 is probably a higher top gear than you need. The only problem is that there is not a lot of choice of 46/30 chainsets, and even less of smaller double chainsets. The obvious one is the Spa Super Compact, which would give you the choice of 46/30, 44/28, 42/26 or even 40/24. To fit one of those you might also need to replace the bottom bracket (depends what size the FSA cartridge fitted to the Boardman is) and you might need to replace the front derailleur (possibly not - it's only likely if you choose a very small chainset like 40/24 and cannot then lower the current front mech enough without it fouling on the chainstay in the small ring).

Comparison of 50/34 vs 42/26 chainsets with 11-28 cassette

Gazelain
Posts: 15
Joined: 13 Aug 2019, 11:06pm

Re: Newbie Cassette Question

Postby Gazelain » 14 Aug 2019, 2:44pm

fantastic,

thank you for taking the time to respond. i'll have a look into the chain set too.

i guess my only concern is how much money I fold into a bike that I am likely to replace over the course of the next year or so (potentially). as the wheels that I am being donated are free - my main objective is getting them on the boardman, therefore i'm thinking the previous advice of the 8 speed 11-32 cassette would be a great option considering the cost, which is minimal - around £20 - plus the chain tool to remove it.

however, I will look into the chain set as an optoin also.

many thanks

Jamesh
Posts: 500
Joined: 2 Jan 2017, 5:56pm

Re: Newbie Cassette Question

Postby Jamesh » 14 Aug 2019, 3:21pm

If you pop into a bike library they will more than likely sell you one at cost less than £10 also might have a spacer and possibly fit it for you too.

My local one has them for such a cheap price.

Cheers James

thelawnet
Posts: 2130
Joined: 27 Aug 2010, 12:56am

Re: Newbie Cassette Question

Postby thelawnet » 14 Aug 2019, 4:52pm

Gazelain wrote:the Boardman is an OK bike, but certainly for a beginner. I had a go on my mates Scott, it's a fair bit better which I could tell fairly quickly - I will look to upgrade it at some point in the future but will serve me well in the meantime.

having said that, i've signed up for the 100 Ride London 2020 - so might fancy the upgrade before that :) lol.


you'll get far more from riding up grades, so to speak, than buying upgrades.

main upgrade is tyres, most other things are a bit of a waste.

Gazelain
Posts: 15
Joined: 13 Aug 2019, 11:06pm

Re: Newbie Cassette Question

Postby Gazelain » 14 Aug 2019, 7:42pm

Thanks again all! What a welcome to the forum, amazing knowledge from you all - and some quality and helpful advice.

@thelawnet - what tyres do most people run (apologies for going off topic slightly).

The boardman has Vittoria Virtuosos. Seem cheap but I've covered around 450 miles so far and not had a puncture, which I hear is quite impressive.

Keen to know what I could go to though.

Cheers

Gazelain
Posts: 15
Joined: 13 Aug 2019, 11:06pm

Re: Newbie Cassette Question

Postby Gazelain » 14 Aug 2019, 7:44pm

Jamesh wrote:If you pop into a bike library they will more than likely sell you one at cost less than £10 also might have a spacer and possibly fit it for you too.

My local one has them for such a cheap price.

Cheers James


Thank you James, new to the terminologies. Library I assume is a local bike store?

Thanks

thelawnet
Posts: 2130
Joined: 27 Aug 2010, 12:56am

Re: Newbie Cassette Question

Postby thelawnet » 15 Aug 2019, 9:21am

Gazelain wrote:
Jamesh wrote:If you pop into a bike library they will more than likely sell you one at cost less than £10 also might have a spacer and possibly fit it for you too.

My local one has them for such a cheap price.

Cheers James


Thank you James, new to the terminologies. Library I assume is a local bike store?

Thanks


no

https://bikelibraries.yorkshire.com/

thelawnet
Posts: 2130
Joined: 27 Aug 2010, 12:56am

Re: Newbie Cassette Question

Postby thelawnet » 15 Aug 2019, 9:40am

Gazelain wrote:Thanks again all! What a welcome to the forum, amazing knowledge from you all - and some quality and helpful advice.

@thelawnet - what tyres do most people run (apologies for going off topic slightly).

The boardman has Vittoria Virtuosos. Seem cheap but I've covered around 450 miles so far and not had a puncture, which I hear is quite impressive.

Keen to know what I could go to though.

Cheers


they are a bit draggy

https://www.bicyclerollingresistance.co ... slick-2015

(I think this is what you have, rather than virtuoso? or maybe they are Carrera virtuouso)

most popular here is Vittoria Hyper but they are discontinued. there are lots of good tyres if you want to spend £40 each

Gazelain
Posts: 15
Joined: 13 Aug 2019, 11:06pm

Re: Newbie Cassette Question

Postby Gazelain » 15 Aug 2019, 9:47am