[Closed] Singlespeeding 12h+ Races: Advice and Ratios?

2 to 1 is normally associated with 26inch wheels on a 29er that will be noticeably harder.

But ultimately you will just have to try it because each course is going to favour a different ratio.

If there is alot of uphill and you'll get tired you will probably need to choose something spinner than what you use for a 2 hour blast.

I find 32:17 (on 26", so ~48 gear inches) is a really good balance for off road stuff, there's enough initial resistance to give some control but it's still low enough that your knees won't explode up steep stuff.

Ah, good to know. I run 27.5+ on the Stooge, so extenal diameter is near as dammit the same as a 29er.

I've seen 32x19/20 discussed, which seems popular...

48 gear inches

Now that's something I can work with - used to using Gear Inches for fixed road/track stuff. Perhaps try a 17 then for 1 - 3 hr training rides and gear down for the race/s.

I’ve seen 32×19/20 discussed, which seems popular…

Yeah, that's around 48 gear inches 😎

For fat-rubbered 29er I run 32/18 for flats, and 32/20 for hills (never done more than 1000m up though, 12hr race in hilly terrain can have much more climbing than that).

If the course has lot of short climbs, you can try harder gear. If it's going to be few longer climbs I wouldn't go below 32/20.

I've raced at Newnham Park (24/12 venue) a few times before in XC and Enduro disciplines and it's certainly not short on some punchy hills. There are a few more drawn out climbs but I'm not sure if they tend to feature in the 24/12 course, I assume at least one of them will as you'll need to gain the elevation somehow.

Don't want to go too hard, even though I would be pre-disposed to, as I've not done much over 3hrs off road before and while I've done 75+ hilly miles fixed on the road that's a very different proposition when it comes to pacing. Would rather finish slowly than burn out fast!

i run 32 (wonky) 18 on my SS... short course XC races, 4-6 hour endurance races, and 100+ km long XC rides.
Seems to be the perfect gear about 16% of the time 😉

DrP

I’m on 30 x 17 on my Singular Rooster 29+, fine on summer 2.8” tyres but hard work on 3.0” Minions in slop. Local hills are steep but relatively short lived (think edge of Peak District).

Personally for any 24 hour race I’d prefer easier gearing as would want to sit and spin instead of being out of the saddle for 18 of those 24 hours and happy to forego top end speed on flat and downhills where I’d be coasting anyway to save energy.

Even the people that SS these longer races successfully seem to show up with some sprocket options, ride a lap and then search last minute for something else 🙂 It is so person and course dependent it is hard to say.

Some people try to pick a ratio to stay on the bike on all climbs (@andrewh has mentioned in the past avoiding cramp by constantly being on and off) and others figure they are happy to get to a point and run the rest.

Most people on the internet will probably suggest a gear too hard for most people's needs as either a) they genuinely prefer it or b) the normal SS posturing comes out to play 😀

For me personally, I would start at 32/19 or 32/20 and go from there.

There are a couple of really speedy and successful SS endurance peeps here on STW so they will be far better placed to advise 🙂

Great thread topic and watching with interest

Yes, for some reason I don't seem to get cramp. A whole host of other issues, but not cramp.
IIRC for 24/12 I used something like 30/19 on a 29, there's no big climbs and that felt fine. If you can have a couple of wheels with different ratios then do so, pop an easier gear in when it starts to get really hard. I have a tensioner rather than slidy dropouts for this reason, takes 30secs to swap a wheel over and no messy about with chain lengths.
Oddly enough, the hillier a course the better I find it on an SS. For example Fort William, use a suitable gear for the big climbs and you'll be fine, the descents are techy enough that no-one will be pedaling that much so you won't a lot of speed there. A flat course like Brazil was terrible for SS, you still need to gear for what climbing there was but then I'd lose out on all the flat, fast sections as chain gangs would charge passed at 25mph with me spinning like crazy at 17mph and totally unable to get on the back.
Anyway, my advice would do a practice lap or two, find the hardest (long) climb and work out what gear works for that, add one more tooth to the sprocket and go with that, and a spare wheel/bike two teeth bigger if you can.
I am very light and have no power though, a lot of SS riders push bigger gears than me, faster on the flat but I just couldn't use them on the climbs.

24/12 is a tough race with plenty of climbing, some of it pretty steep.

That Said @danw sums it up pretty good, take several ratio options and find the one you can stomach for 12 hours.

When I've raced 24hr events I've used 32/20 if thats any help.

Most people on the internet will probably suggest a gear too hard for most people’s needs as either a) they genuinely prefer it or b) the normal SS posturing comes out to play

I’ll come out and suggest 32:18 for 29er and probably ok 27+. I’m on 33:18 just now for parts availability reasons tho.

So maybe I’m posturing, but I’ve also been riding SS about 18 years now so the legs are probably used to it.

If you want definite posturing the only race I’ve ever won was 12hrs and I was on 32:18 so it’s obviously the best ratio 😉

I'm on 30*18 on a rigid 29er 2.4" tyres. Find it's good for my area which is pretty hilly.

Thanks all for the excellent advice!

I’ll have my primary 27.5+ wheelset but will also pinch a pair of 29ers off my trail bike which will also allow for flats and other mechanical issues too.

I’m putting the geared drivetrain off the Stooge onto the new trail bike in the next week or so will probably start on a 19t for my local riding and go from there.

I'm sure there be other threads coming in due course about training, nutrition and the like as we get closer to the event, for now I’m just going to ride my damn bike!

Ordered Surly 18t and 19t to start with - got a few pretty steep, loose tracks leading up onto the moor that appear on most every local ride so going to fit the 18t first with a view to muscling it around for a few months and reviewing.

Managed to find some NOS Chris King cogs at a shop in the Netherlands but as much as I wanted to justify them, at nearly £100 each (once postage was added on) it was a step too far so settled on good old Surly.

I'd be sticking the 29er wheels straight on with a nice fastish tyre. Drag is the enemy for me on a singlespeed.

Choose a gearing with the same policy as the hour record. First third should be so easy you think you've got it all wrong. Middle third will be about right. Last third you should be clinging on 😉 (maybe keep another gearing for that, even the time spent swapping a wheel or even changing a cog on a wheel will be relatively little compared to riding the wrong gear for 6 hours. And you'll have a spare wheel anyway won't you, in case?)

I've not done many endurance events but the hardest on SS for me was D2D at Thetford, as others have said where it was flat but twisty there's relatively little coasting, it was all pedalling, and once the gear gets a bit too big every time you have to pedal out of a corner on a gear that's a bit too hard, another bit of your soul drips out of your legs.

as I’ve not done much over 3hrs off road before

And you're considering a SS for 12h races?

3 hrs is barely getting warm, I'd leave the gears on and go and do a few full day rides first.

I keep two Surley cogs on the freewheel instead of one. The bike has rear facing dropouts for an Alfine hub, so switching for different terrain is possible (after a test ride). It’s 2:1 on 26” and a little lower. Single speed off road is easier than fixed on road. You do get to rest a bit! I ride a LOT of fixed on 3:1 (82”).

But if you are used to fixed wheel n the road, single speed will be fine. I much prefer it off road.

And you’re considering a SS for 12h races?

Yes, partly because I'm a sucker for a challenge, and partly because I'm porting the drivetrain over to my new trail bike and don't want to buy a new one!

In seriousness though, I've ridden fixed gear on the road exclusively for about 4 years and done some 7h days (and steep hills) on fairly big gears, I've also done a 12h+ loop on a Surly 1x1 singlespeed but that was mostly road. I'm fairly sure I know what I'm getting myself in for, I also want to reduce the risk of mechanical failure on a big race like that which I'll be training for for 6 months or so in the lead up.

I’d be sticking the 29er wheels straight on with a nice fastish tyre. Drag is the enemy for me on a singlespeed.

@Joshvegas, good idea - I'll be trying them out on the Stooge, but they're Hope Enduro (for my trail bike) so fairly portly compared to my carbon 27.5 wheelset. I have a few different tyre options to play with, Newnham can be fickle regarding conditions depending on the weather. I use Rekon+ front and rear for general use, but could go more aggresive on the front, less aggresive on the rear or fatter all round as needed. Or slap the 29ers in there - thankfully it's the same spacing between the bikes!