What cassette would you match with a 48T single crankset?

[pandorapi]

Hello, I am a complete newbie to road bikes and bicycle building. So far I have been happily riding my three speed Raleigh Caprice daily around London, and it's a great commuter bike. But I want to be able to do longer and harder rides outside the town, and with my dutch style bike it's a struggle.

I bought a second-hand Reynolds 531 with 27in tyres and thought I could fix it up to use. However currently it is a struggle pedalling on it, because I am assuming the crankset to cassette gears ratio is not good for me. The bike has a single 48 tooth 165 Sugino crankset.

My initial thought was changing the crankset to one with less teeth. But I would prefer a single crankset like it currently has because seven gears is plenty for me, as I never plan on climbing mountains with this bike. Unfortunately single cranksets are an expensive rarity. I am now considering changing the gear cassette instead.

My questions are: is a single 48T crankset too hard a crankset to keep and would a 42T like my initial thought be better? If I was to keep the 48T crankset, what gear cassette would you propose I match with it? I mainly plan on cycling around the English countryside that is hilly, but has no mountains. Also I am not very interested in high speeds, but rather in long distances. Also if it makes a difference, I am a woman and not particularly tall.

 

[tincaman]

I would go for the 42T up front and a 12-32 cassette, then you are covered for hilly areas

 

[Tim Hall]

Morning and hello! You don't say what gearing you currently have on the bike, so it's a bit hard to advise. As a side note there's a fair chance that you have a freewheel, not a cassette on there (here's an article showing the difference). Once these things are known it'll be a bit easier to identify a suitable easier to pedal replacement.

 

[I like Skol]

You need to let us know what gear range you currently have at the rear cluster. Just count the teeth on the smallest cog and the largest cog and let us know what they are so we can give you a few pointers on your options.

 

[Ajax Bay]

The bike has a single 48 tooth 165 Sugino crankset.

The 165 is the length of the crank arm in mm and since the OP is not tall, it's an excellent length. To offer sound advice it would be useful to know:
1) the number of teeth on the largest and smallest sprocket (cog) on the back
2) whether it is a freewheel or a freehub (see @Tim Hall 's link above)
3) the number of bolt holes in the chainset and the exact distance between two adjacent holes (as @Dogtrousers has asked) (?5 and 76.4mm)
4) The distance between the inner side of the chain ring and the edge of the frame's bottom bracket shell (where the pedal axle goes through).
But pending this additional info, mirroring 'first responder @tincaman I'd say change the 48t for a 42t (if 130 BCD) and get a 'MTB' 7 speed cassette (12-32) or freewheel block (14-34) on the back.

 

[jowwy]

The 165 is the length of the crank arm in mm and since the OP is not tall, it's an excellent length. To offer sound advice it would be useful to know:
1) the number of teeth on the largest and smallest sprocket (cog) on the back
2) whether it is a freewheel or a freehub (see @Tim Hall 's link above)
3) the number of bolt holes in the chainset and the exact distance between two adjacent holes (as @Dogtrousers has asked) (?5 and 76.4mm)
4) The distance between the inner side of the chain ring and the edge of the frame's bottom bracket shell (where the pedal axle goes through).
But pending this additional info, mirroring 'first responder @tincaman I'd say change the 48t for a 42t (if 130 BCD) and get a 'MTB' 7 speed cassette (12-32) or freewheel block (14-34) on the back.

why 7 speed cassette or freewheel, when your unaware of what shes already using??

 

[boydj]

A 48 tooth chainring has got to be pretty hard on any decent hill, even with a 32 cog at the back. I'd go with a 42 or a 44 depending on the locality and the hills that will be encountered.

 

[Ajax Bay]

why 7 speed cassette or freewheel, when your unaware of what shes already using??

Not quite sure what you're driving at, but if it's 'the current sprockets may be fine' then I did say "pending this additional info" and I provided the links to help the OP see what we're talking about. I agree with your implication, with a swap to a 42t chain ring. If my guess at the BCD is correct then the smallest chainring available is a 38t.
The bike's 7 speed and will be either cassette or a freewheel block. Since "currently it is a struggle pedalling on it," I'm deducing that the current largest sprocket is a 25 because a 48/27 ratio gear is starting to be reasonably easy to pedal on the flat, but individuals' 'struggle' thresholds are just that: individual.
I suspect that the limiting factor on the largest sprocket that can be fitted will be the capacity of the RD (as @Dogtrousers has intimated).
I note OP has not been back since the late night shipping forecast, shortly after posting.

 

[jowwy]

Not quite sure what you're driving at, but if it's 'the current sprockets may be fine' then I did say "pending this additional info" and I provided the links to help the OP see what we're talking about. I agree with your implication, with a swap to a 42t chain ring. If my guess at the BCD is correct then the smallest chainring available is a 38t.
The bike's 7 speed and will be either cassette or a freewheel block. Since "currently it is a struggle pedalling on it," I'm deducing that the current largest sprocket is a 25 because a 48/27 ratio gear is starting to be reasonably easy to pedal on the flat, but individuals' 'struggle' thresholds are just that: individual.
I suspect that the limiting factor on the largest sprocket that can be fitted will be the capacity of the RD (as @Dogtrousers has intimated).
I note OP has not been back since the late night shipping forecast, shortly after posting.

Where does the OP state that its 7 speed though? Or are my eyes failing me?

 

[Tim Hall]

Where does the OP state that its 7 speed though? Or are my eyes failing me?

Third paragraph.

But I would prefer a single crankset like itcurrently has because seven gears is plenty for me,

 

[jowwy]

Third paragraph.

my eyes definitely deceived me then lol

 

[T4tomo]

Its easiest to stick with current rear 7 sprockets (assuming they aren't too worn) and from likely age of bike there is unlikely to be a dinner plate 32/34 bottom gear. My 80's touring bike has a 14-28 for example, "racing" bikes of the time would have 23 or 25 as biggest sprocket. I'd be tempted to go with a 36T or 38T single front sprocket. Definitely err on the side of being lower rather than higher. Its easier to freewheel some down-hills, than push up some up-hills, maybe even a 34T depending on what is on the rear.

note you will need to shorten your chain a bit when you fit the new sprocket. I'd go with a new one.

I run a single front set up on my winter bike, that's a 38T with an 11-32 10 speed rear. That can get me up anything I need to, but I'm a reasonable strong bloke who cycles a lot.

 

[pandorapi]

Thank you for all your replies! I managed to get round to rechecking what I actually have on my bike.

1. The ring on the crankset is one complete piece, so I can not take of part of it. But it looks like it is not a single piece with the crank arm, but I do not have the right tool at the moment to try and take it apart. (I'm putting some photos below)
2. I completely miscounted the amount of sprockets I have at the back. It turns out they are only five. The biggest is 28 and the smallest 14. Due to the age of the bike I assume its a freewheel. I didn't quite understand how you can tell from looking at it.

Now that I realise I have 5 gears at the back, I am re-thinking things. Should I just get a classic double crankset for the front, even though that would mean adding a second gear shifter and getting hold of an vintage old-school style one might be very difficult? Or should I go for the 42T or 40T or 38T (so many proposals!) single crankset in front and add some more sprockets at the back. I am assuming that freewheel means you can add single sprockets as needed since they are not a joined block.

 

[KneesUp]

If you want a cheap single crankset, they are available - I bought one of these with 33t for the kid's bike and it seems fine - they also do 38t, 44t and 46t.

It won't look as nice as the one you have, but older bikes do seem to have high gearing. SJS have a range of freewheels if you wish to go down that route. They also have a range of shifters, although you might be as well getting second-hand ones if you want to keep it matching.

 

[SkipdiverJohn]

• Before doing anything, I'd look for any obvious causes of drag, such as tyres not inflated hard or stiff wheel bearings etc, due to lack of greasing. A fairly light bike with a 531 frame in decent mechanical order should not be particularly hard going to pedal, with a 14-28 rear cluster and a 48T front. It's bottom gear ratio will still be a bit lower than the low gear on your 3 speed.
• TBH, I would not attempt to convert a 5 speed bike to a 10 speed unless I happened to have all the bits I needed kicking around, so the cost was minimal. Once you start adding up the expense involved in sourcing additional gear parts you haven't got in order to convert a 5 speed to a 10 speed, you'd probably be better off buying a secondhand 10/12 speed flat bar tourer/hybrid bike, which would probably come with a 38/46 or 48 double front ring and if you are lucky, a 14-28 six speed freewheel that would give you closer ratios in the higher gears.
• For example there are loads of Ladies frame Raleigh Pioneers to be found on eBay (I assume yours came from there as I'm sure I spotted a similar bike recently) and all except the poverty-spec models will have at least 10 speeds, and the better ones can be found with Reynolds 501 frames.