Gear Ratios

[buzzy-beans]

My word, I am embarrassed by all the time you amazing lot are giving to me!

I hate what I am about to write, but I will go and find the violin and start playing the "I am a poor hard up basic state pensioner" tune and as such my budget is exceptionally tight!!!!

As such and if I were to stop with the existing 52/42 chainrings and simply fit a new 11/28 cassette as Bigssy has suggested which would appear to be the cheapest option, what kind of % improvement would that give me?

 

[Tigerbiten]

At the moment you have a 42/19x27 = 59.6" bottom gear. With a cadence of 60 rpm you will be doing around 11 mph.
You will have a 42/28x27 = 40.5" bottom gear. With a cadence of 60 rpm you will be doing around 7 mph.
So around two thirds the effort to climb hills.

Can you find a 12/28 Shimano CS-HG50 7-Speed Cassette (£10.95 at Wiggle) as the steps between the mid gears is better, 12-14-16-18-21-24-28 vs 11-13-15-18-21-24-28. The 15-18 step is nasty and is right in the middle of what I think are your cruising gears.

If you've a long cage derailleur it's possible you may be able to fit a 12-32 cassette.
The would drop you to a 35.4" bottom gear and that would drop you another 1 mph hill climbing.

 

[Ajax Bay]

Up front there are two rings of 52/42 [and at] the back the cassette is a 7 speed 13/19

http://www.gear-calculator.com/?GR=DERS&KB=42,52&RZ=13,14,15,16,17,18,19&UF=2240&TF=90&SL=2.6&UN=KMH

if I were to . . . stop with the existing 52/42 chainrings and simply fit a new 11/28 cassette

http://www.gear-calculator.com/?GR=DERS&KB=42,52&RZ=11,13,15,17,20,24,28&UF=2240&TF=90&SL=2.6&UN=KMH
13-28t cassette
eg from SJS
I'd replace the 13-19t 'corncob' cassette with a 13-28 (link above). The 52/13 ratio will be quite enough for your fastest cycling: you definitely don't need an 11t.
Then go out and ride. If you want a lower gear than 42/28 then swapping the 42 for a 39 will give you a further 7% advantage. But do the cassette replacement first and try it out.
HTH (and in plain enough English)
Edit:

a 12/28 Shimano CS-HG50 7-Speed Cassette

http://www.wiggle.co.uk/shimano-cs-hg50-7-speed-cassette/

 

[buzzy-beans]

So many thanks to you three guys, I will do exactly as you suggest and order the 12/28 cassette as well as a new chain.

And by the way your English was at such a level that even I was able to decipher the content of your combined advice which is saying something for me!

 

[ColinJ]

So many thanks to you three guys, I will do exactly as you suggest and order the 12/28 cassette as well as a new chain.

And by the way your English was at such a level that even I was able to decipher the content of your combined advice which is saying something for me!

I think the 13-28 would be better for you; you won't get much use out of a 12!

PS And Reiver's 13-30 would be probably better still, if it works with your derailleurs.

 

[Ajax Bay]

[QUOTE 4987920, member: 9609"]Is it definitely a 'Freehub' that you have ?[/QUOTE]

I agree with @ColinJ , but all the specific to product advice/suggestions (ie Wiggle/SJS) depends on you having a freehub/cassette. If you have a freewheel the sprocket size advice still stands, though.
Sheldon

 

[SpokeyDokey]

Thanks for the replies guys. As you can see already it is a complicated subject and I appreciate your help.

Here is the situation I have at the minute.

I have a Genesis Croix de fer 20 and I expect to be going up some very big mountains next year. I want to be able to spin up the mountains and cruise on the flats.

I get the drift of your post but does anyone on here really 'spin' up mountains?

As someone who is seriously contemplating a 38 x 42 lowest gear 1x and who finds 34 x 32 up steep-ish hills, let alone mountains, an effort: that is an out of reach cycling mode for me.

 

[steveindenmark]

I almost span, spun... up Monte Grappa in the summer. I now know I need more gears.

 

[buzzy-beans]

[QUOTE 4987920, member: 9609"]Is it definitely a 'Freehub' that you have ? and do you have the tools to remove the old one ?

if you want, I have a 7 speed 13/30 that I have no use for, it has probably done about a 1000 mile so plenty of miles left in it (I changed it for a 14/32 which suits my hilly terrain better, I need all the help I can get)[/QUOTE]

I am so very sorry, but I missed your post!!

I have now ordered as suggested an HG cassette and as for knowing if it is a Freehub or not I haven't got the foggiest idea, however I can only assume it is as Bigssy from whom I bought this beautiful Shorter from suggested one of these types of cassette................ I can only hope he knows what he is talking about, which having met him, I feel very confident he does

 

[swansonj]

I get the drift of your post but does anyone on here really 'spin' up mountains?

As someone who is seriously contemplating a 38 x 42 lowest gear 1x and who finds 34 x 32 up steep-ish hills, let alone mountains, an effort: that is an out of reach cycling mode for me.

I think I do. My bottom gear is, from memory, 18-point-something inches, and my preferred mode on long and steep hills is to maintain a cadence around 80 (I sometimes time it as distraction therapy), dropping down the gears till I reach that bottom gear, when perforce, if the hill gets steeper still, my cadence has to slow. Does that count as spinning?

 

[Tigerbiten]

I get the drift of your post but does anyone on here really 'spin' up mountains?

As someone who is seriously contemplating a 38 x 42 lowest gear 1x and who finds 34 x 32 up steep-ish hills, let alone mountains, an effort: that is an out of reach cycling mode for me.

Even with a full camping load, only +20% hills are hard work, without the load then I can spin up most hills.
I use a Schlumpf HSD with twin chainrings (54/38) and a Rohloff (21t sprocket) built into a 20" wheel.
That gives me both silly ultra low (9.5") and ultra high (172") gears on my recumbent trike ......

 

[Tigerbiten]

EDIT EDIT EDIT Now having been out to look at the cassette fitted to the bike it appears that the one fitted doesn't look like the type ordered as the area closest to the hub is smooth and not castellated at the innermost point................... so hopefully it isn't too late to cancel my order, fingers crossed.

Look at Sheldon Brown's page (https://www.sheldonbrown.com/free-k7.html) to work out if you have a freewheel or a freehub cassette. 5/6 can only be a freewheel. 8+ can only be a freehub. But 7 speed can be both.
Sorry, I knew that but didn't mention it ........

If you do have a screw on freewheel cassette, then a Shimano Tourney TZ21 7-Speed Cassette 14/28 will work. Chainreaction cycles
If you have a slide on freehub cassette, then a Shimano CS-HG50 7-Speed Cassette 12/28 will work.

 

[SpokeyDokey]

I think I do. My bottom gear is, from memory, 18-point-something inches, and my preferred mode on long and steep hills is to maintain a cadence around 80 (I sometimes time it as distraction therapy), dropping down the gears till I reach that bottom gear, when perforce, if the hill gets steeper still, my cadence has to slow. Does that count as spinning?

@swansonj

Ok, ok... I'm a hill wimp. I need to get out and cycle more and build my little legs up.

 

[swansonj]

@swansonj

Ok, ok... I'm a hill wimp. I need to get out and cycle more and build my little legs up.

Ooops. My apologies because I wrote a post that appears to have allowed you to take almost the opposite meaning to the one I intended.

My point was that I do spin up hills - because I have fitted what most people regard as a ridiculously low gear to allow myself to do so.

I don't agree with the term "wimp" so let's talk in terms of fitness and leg strength. I think you are assuming that anyone who spins up hills must be pretty fit. But that only applies if you restrict yourself to current conventions of so-called "road bike" gearing. I am not terribly fit and in particular I have only a limited capacity in my legs. My solution of sub-20" gears allows me to spin up mountains at my own rather slow speed, conserving my legs, being overtaken by virtually every other cyclist on the same hill - but crucially, able to keep going all day, and even more crucially, enjoying myself.

Each to their own say I.

 

[buzzy-beans]

Look at Sheldon Brown's page (https://www.sheldonbrown.com/free-k7.html) to work out if you have a freewheel or a freehub cassette.

Thank you a zillion times over for that amazingly interesting link, it is now copied to my must read files.

Having now had time to thoroughly look at the cassette fitted to my bike and having read the pertinent section of the link you provided, I am now certain that the Shimano 12/28 freehub cassette I have ordered should be a perfect fit.

Unfortunately, due to my left hand being out of action due to surgery last week, I will have to do nothing other than look at and occasionally polish 'PB', the newly acquired and beautiful 1970's or 80's Shorter & Rochford for at least another 14 days if not a great deal longer until all the swelling has gone down and I have regained use of it.

Yet again, many, many thanks to all of you for giving this luddite your time and attention.