I recall being educated on decent single speed ratios on last years BB200 by Jase... But I forgot. I think he said it should be a third on the back, of what you have on the front. So (I'd translate that as) a 42 front chainwheel would want a 14 rear sprocket??

Reason why I ask is that I'm (not going SS) going 1x on the roadie commuter. It has 1400ft of climbing over 40 miles there.... Another 1400ft up on the way back but this time it feels alot harder. Maybe cos its post-work or maybe cos the hills back are longer ups and all come in the last 25 miles. I dunno, but it is what it is...

Question to the lock and unlocked community being, whats an optimum SS ratio for such a commute (80 miles return with the steepest sections only being 10 to 13%)...

Currently in the thinking of a 42 front cog (its the cheapest and biggest available, so I don't get bored nor slowed down trying to get there) with an 11 to 28 cluster at the rear. That gives me an effective SS ratio of 42-14 if I so wished but a few extra cogs to go faster on the downs/flats but plenty on the way up...

11 - 25 rear cluster would be lovely*, but I'm only building/buying this once. So wanna get it right... So would appreciate your educated judgement(s)...

Ta in advance

*Obviously I'd save another 25 or so grams, but whocares about that... whats a bit of weight

Hi, I think it depends a lot on the watts you have in your legs. I weight under 60kg with no much strength in my legs and have to go easy with the ratios.
I wouldn't say it's a hilly route but being a commute ride is better to play safe. I crossed Europe on 38x18 including some mountain passes in the Alps and the climb to Pico Veleta.
You could try 42x18 or 42x17.
Check out gear calc website to compare ratios?

You’ve confused me Shaf- are you talking about a single front chainring and rear cassette or single cog on the back as well?

And when Javi says he’s not strong, he’s a mountain goat - climbs everything and anything on a single gear

Javi... Yes, I know about his Steven even climbs tress to get across broken banks of rivers. Didnt realise he was only 60kg though

I'm gonna be 1 ring upfront... An 11 speed cluster at the back. The reason for the question was so that I dont end up undergeared. Really want yo have an 11 to 25t rear cassette. But then the lowest gear would be 42 x 25. Doing this on a nice hilly commute after a 12 hour shift for 40 miles. Am I gonna end up crying to myself about it

It's a Dura Ace cassette I'm buying you see, so can't be spending that kinda money again (for a good while) and need to get it right first time. Single speed was a past dream that never materialised after speaking to Jase on that ride through Wales of 2019...

Wheel size is also a factor to consider Shaf.

With 26" a ratio of 2:1 was always a good starting point for off road, so something like 32:16.
With 29" (700c) 32:18 would feel roughly similar.

I'd not much experience of riding lots on-road SS, but i say definitely go for a bigger ratio.

Don't ask me why, but riding a bike with gears, even in the same ratio, does not feel 'the same' as riding single speed.
Saying that, it will give you an indication of the effort & technique needed for climbing & spinning on flat sections.

Can't beat a good single speed off-road, there's just something about it that hits the spot

P.S. Javi is a pocket rocket of a machine!

iMHO if its not for flat and just general use i would go bigger personally as it will always give you [bale out ] options and you will have the same hardest gear
I have never ridden on the roads SS so I have no idea what ratio I would want but terrain would be the deciding factor and over 40 miles in parts its going to be suboptimal -even my 325 ft of " climbing" commute has most of that in one sharp steep hill and the ration i would want for the rest is going to be very hard up that .

EDIT; I agree with off road there is just something magical about the no gears no chatter/noie and when you want to go faster you pedal harder and something so joyous about reaching a steep part tired and then attacking it and then slowly grinding your way up

a 42 front chainwheel would want a 14 rear sprocket

A 3:1 ratio is pretty common on track bikes (the hire ones at Manchester velodrome run 48:16). I'd say that's a bit ambitious for a hilly commute.

Nothing like 'measure twice*, cut once'. All comment noted and I'll go for the 11-28 cassette which still saves me 18g from the 11-30 but an extra 3 teeth from the 11-25 will make it a more adaptable bike**

Much appreciated

*Ie. In this case asking those in the know as the Prophet Muhammed (sallallahuAlayhiWasallam/PBUH) taught us to the effect that,

"The cure to ignorance is in asking."

** The front ring is a 42t AbsoluteBlack I have my eyes on and it'll save my Dura Ace compact rings. Those I can then use if ever using the commuter bike for longer journeys... but would need to put a front mech on obviously.

I used to use 39-17 for SS CX, 2.3:1 on a 35-40mm tyre. My SS road bike is 46-18 I think, about 2.5:1, though it rarely gets ridden as the hills here are just a bit steep for a gear that isn't frustrating on the more open roads. The CX bike goes up road hills easier for a bit further, it's a bit spinny on the flat though.

Single-speeds .. daft idea eh : )

Could be worth putting an oval ring on it if the gear doesn't quite work for you, ime they seem to help me get a bit further up hills before stalling as well as turn them over at speed more smoothly. I was on a 32 round on my 29er, went to a 34 oval w/o any issues with the slightly bigger gear. It's like it adds a bit at each end?

Thanks James. Yes, I forgot to say, its a 42t oval ring. Mainly cos thats what I've seen on offer and its only 71g but the ovality is something I thought I'd not get too excited about. You've given me hope

Shaf, im concerned about this plan.

I work a 10hr shift and a 27 mile each way commute across Anglesey is enough for me to not want to do it the second day.

Its now Nov, so the wind is stronger, and the weather a little worse.

40miles in inclement weather can easily take 3 hr with mudguards and a bag of your work kit preventing you being super aero. So when you factor in a shower and getting changed thats 18.5hrs you are away from home and 'working'. Add in a shower at home and some food and its about 4hr sleep before you have to do it all again.

That sounds super hard to me. I apologise if im doing you a massive dis-service, you may be Chuck Norris on a bike. I think ive made it clear im a massive softie, but i would hate this plan to be the undoing of a fun forum member.

Regards

Ian

Javi wrote: ↑Thu Nov 12, 2020 10:52 pm I weight under 60kg with no much strength in my legs and have to go easy with the ratios.

Javi that is such twaddle - I remember following your once per rev skid marks on the climb out of Glen Moriston whilst I gurned up in 28/42!

For road 1x I've got a 42 - 11/32. Its OK but when the 42 wears out it will drop to a 40. Gravel 1x I'm on 38 - 11/40 (cheap 9 speed sunrace) which covers most terrain.

BreninBeener wrote: ↑Fri Nov 13, 2020 11:10 am Shaf, im concerned about this plan.

Don't be Im not Chuck Norris and before thinking about 80 miler round, I was doing 40 miles just the one way and choosing my shifts carefully (5 years as a 0 contract agency where I chose when I wanted to work there). Now I'm working there contracted and have been since Jan. Riding in with my steel Bertoletti (the default main bike) and riding back (when I can be bothered).

I choose when I'm gonna ride in or out carefully. Being 2 shifts a week there with 1 week per month being the one shift, I doubt I've an excuse for not riding all of it. Done the return trip now at least a good few times to know it can be done... and, and, my commute runs past at least 2 train stations for the days I'm feeling super-soft

htrider wrote: ↑Fri Nov 13, 2020 11:23 am

Javi wrote: ↑Thu Nov 12, 2020 10:52 pm I weight under 60kg with no much strength in my legs and have to go easy with the ratios.

Javi that is such twaddle

It made me laugh as well We have

60kg with no much strength in my legs

and

I crossed Europe

in the same reply

I too have watch Javi levitate up impossible climbs when I was off and pushing (running) trying to keep up

Haha! Ok, but road ss on ondulating terrain is miles different from hilly off road where weight matters more.
Such long commute!!

Javi wrote: ↑Sat Nov 14, 2020 6:58 pm Haha! Ok, but road ss on ondulating terrain is miles different from hilly off road where weight matters more.
Such long commute!!

you're humbeless makes me smile. I'll make sure I've a low enough ratio included in my 1x to ensure some comfort. Haven't done my commute for well over 4 weeks now (had covid isolation for 2 of em) and it seems I'm nit even looking forward to it as I'd usually do...

Must push myself tomorrow

If you are going to be commuting that distance regularly, then I would suggest that you can forget about saving a few grams here and there as the weight will drop off you and you will soon be either a racing snake or in a coma in a ditch on the way home after shift 4.

Seriously, why not just get a job closer to home? You a registered nurse I seem to remember, your local Trust will bite your hand off!

Thats actually such a good idea. My local trust is only about 1 mile away or the sister hospital 8 miles. If I applied and got a job at the '1 mile' place I could actually walk it there and wiild never have to bike-commute by ever again in my life

in a coma in a ditch on the way home after shift 4

Hadn't thought about that... I should ve more careful... It was a stupid idea of stupid ideas... who'd wanna commute home after 40 miles I'm just veing stupid...

Thread closed

Why not keep a double chain ring up front? The weight is minimal, and you told me in the build thread that wasn't a weight weenie project. Just take the second chain ring off when you know what suits, otherwise you are in danger of removing something, realigning the chain, then having to put it back on.

You do know that you will have to space a single chain ring differently if you are using a multiple cluster on the back as the angle of the chain may become too acute. A double chain ring is not actually designed so both rings cover all the cassette, the small ring covers the top 5 or 6, the bigger ring covers the bottom 5 or 6 and you have an overlap in the middle. TGhis may be more complicated than it appears at first.

Just saying, although I am pretty confident you will ignore me

Cheddar Man wrote: ↑Sun Nov 15, 2020 7:07 pm Why not keep a double chain ring up front? The weight is minimal, and you told me in the build thread that wasn't a weight weenie project. Just take the second chain ring off when you know what suits, otherwise you are in danger of removing something, realigning the chain, then having to put it back on.

You do know that you will have to space a single chain ring differently if you are using a multiple cluster on the back as the angle of the chain may become too acute. A double chain ring is not actually designed so both rings cover all the cassette, the small ring covers the top 5 or 6, the bigger ring covers the bottom 5 or 6 and you have an overlap in the middle. TGhis may be more complicated than it appears at first.

Just saying, although I am pretty confident you will ignore me

Nah. Not gonna ignore you at all. But gonna continue as I was I'll see how this commuting stuff gets on

My 1958 singlespeed roadie currently runs 46:16 which is great for round here, can just about get it up frocester hill which is the closest significant climb, (10-12%), was easier when I was running 44:16 but the cadence on the flat was higher than I prefer. I’ve done a century ride this year on 46:16 with 5,000ish feet of climb.

My commute (pre COVID) was 15 miles each way and roughly 1000ft and sometimes used the singlespeed

redefined_cycles wrote: ↑Sun Nov 15, 2020 8:38 pm

Cheddar Man wrote: ↑Sun Nov 15, 2020 7:07 pm Why not keep a double chain ring up front? The weight is minimal, and you told me in the build thread that wasn't a weight weenie project. Just take the second chain ring off when you know what suits, otherwise you are in danger of removing something, realigning the chain, then having to put it back on.

You do know that you will have to space a single chain ring differently if you are using a multiple cluster on the back as the angle of the chain may become too acute. A double chain ring is not actually designed so both rings cover all the cassette, the small ring covers the top 5 or 6, the bigger ring covers the bottom 5 or 6 and you have an overlap in the middle. TGhis may be more complicated than it appears at first.

Just saying, although I am pretty confident you will ignore me

Nah. Not gonna ignore you at all. But gonna continue as I was I'll see how this commuting stuff gets on

Just remember to look at the alignment of the chain when you remove one or other of the chain rings. Yo need to have a straight line from the chain ring to the middle sprocket, removing one or other of the rings won't give you that, you need to do some jiggery pokery with where the ring attaches, and possibly even a different bottom bracket to bring the chain ring or take it out depending.

Also, if you are removing the front deraillieur guide, then you will be removing a kind of chain guide/retainer at the more acute angles, and you may need to replace that to stop the chain slipping off when on the smallest or largest cog.