XC bike weight. How low can you go?

I’m rather proud of my new build, at 21.5lbs for a FS ally 29er running 3×9 I think it’s rather good 8) Plus I reckon I could take another pound of it easily if I really wanted to.

Giant Anthem X 29er frame (L) with Fox Float RP23 Boostvalve
Fox F29 FIT RLC forks, 15QR thru axle and tapered steerer, 100mm travel
Giant FSA tapered headset
XTR SIS gear cable set
Shimano BB71 Press-Fit Bottom Bracket
FSA K-Force Light XC Chainset MegaExo
XTR pedals
Thomson masterpiece seatpost
Ritchey WCS Carbon Flat Bar
Ritchey WCS 4Axis Matrix Stem
Hope mono mini pro’s in Team Issue Green, Ti bolted
X0 Twist grip changers
X0 Rear mech with KCNC jockey wheels
XTR front mech
KMC SL chain
160mm Ashima rotors, Ti bolted
PG990 cassette
American Classic hubs (15mm front, QR rear)
DT Super Comp spokes
Stans Crest rims
Alloy nipples
Racing Ralphs 2.25s UST front and back
Fizik Arione saddle

DP doh!

No chain guide at the moment. As the Renthal ring begins to bed in (now 400 ish miles old) it’s beginning to drop every now and again.

Apparently superstar are going to launch a clamp mounted XCR which will be around 45/50 grams and £16 – I’ll probably pick one up.

Bream, It’s no good bragging about your bike without pics (especially twice). It might just be a fantasy you’re living out 😉

B.A.Nana
Bream, It’s no good bragging about your bike without pics (especially twice). It might just be a fantasy you’re living out

Pressed return twice mid type = doh!

agree on the lighter stuff can be strong. I’ve got a very lightweight front wheel which is over 10 years old and still going strong despite a lot of abuse. It’s now on the commuter, and just keeps going.

Light stuff is surprisingly strong these days.

Bream did you race Ränneslästuren yesterday?

nice Anthem X there, shame about the wheel size 😉

Apparently superstar are going to launch a clamp mounted XCR which will be around 45/50 grams and £16 – I’ll probably pick one up.

I’ve just bodged a BB mounted Superstar one with a DMR seat tube mount – works really well, never dropped the chain, doesn’t rub. Needs some alu bolts now I’ve sorted the spacing.

Haha bream my td-1 ss weighs the same as your fs 😉 as much as i wanted it to be sub 20

Although its built to last i guess with arches, brooks swallow ti , 2.25 ralph snakeskins

This was my lightest geared hardtail build so far:

It came to bang on 22lb (on my scales, not a spreadsheet). That’s with a sub-3lb frame, SID Race forms, American Classic wheels wearing Speed King Supersonics and an XTR drivetrain and brakes. It didn’t have a particular light saddle or seatpost though, so there were still some easy weight loss areas to target (and I do have lighter bits for that but didn’t get around to fitting them) but going much beyond that was going to get pricey.

The Swedish Chef
Bream did you race Ränneslästuren yesterday?

No, not fit enough yet 😉

Next planned race will be Snapphaneturen.

Nip into a Specialized store and pick up an S-works Epic. Be prepared to say “crikey”.

I forget exactly what they were, but I weighed 2 2011 S-Works Epics, about 21.8lbs IIRC.

still get a bit miffed about these claimed weights myself, but maybe its jealousy?, or cos mine aint as light.

Mines about 21 lb

Spesh carbon stupy
ritchey carbon bars and stem
spech seat
control tech seat post
new xtr brakes, shifters, 2×10 chainset, front mech,
xt rear mech and cassette
alpine rims, ztr hubs, cx ray spokes
racing ralphs
2011 sid xx forks

unsure where to save anymore weight, maybe go tubeless rocket rons and save 1/2lb,and lighter chain and casette is another 1/4lb, but TBH, i’m quite happy with it just now and i dont think an extra 1lb would improev my performance too much. Think even absalons bike is 21lb ish, so not mega light

Interesting reading through this thread, it doesn’t seem like 1xn Drivetrains have as big an impact on overall bike weight as other major build items like Fork/Frame/Wheels or is that a miss-reading on my part?

I saved about 250g I think going from an XTR M988 Race double to a single ring, it’s the LH shifter, cable, front mech and one chainring, plus the added weight of a chain guide.

For me the ratios were spot on – I’d not have done it solely for the weight saving. Fairly irrelevant having a light bike if you can’t ride it up the hills 🙂

Well that was my other thought, so ~250g (0.55Lbs) is all well and good but only if you end up with a usable (or in many cases Raceable) gearing range… Half a pound at the cost of dropping off the pace on a climb seems a bit of a false saving…

Indeed are there any other “False weight savings” that people have found? Where taking a weight reducing measure has actually made the bike overall slower?

Indeed are there any other “False weight savings” that people have found? Where taking a weight reducing measure has actually made the bike overall slower?

Tires surely, wouldn’t like to run furious freds on a wrong day!

I really wanted to try 1x? as I had just built a SS with a 32/14 ratio.

I figured, if I can get that up trails a 32 – 11/32 would give me all the range I need plus the speed on the flats

It wasn’t really a weight saving measure, just simplifying the bike.

Also you need to take into account your size/weight and intended use.

My 20″ 456Ti comes in at 24 lbs with pedals, crud-catcher and bottle cage; it includes ‘proper’ tyres, triples chainset, a 5″ fork and Ti/carbon everywhere – its equally at home in Swinley, Afan and The Peaks. I could probably save another 1/2 lb, but it’d be expensive…

Or maybe my scales are just pessimistic?

if you end up with a usable (or in many cases Raceable) gearing range

Indeed, and the only times I’ve wanted a slightly lower gear is while racing. When riding you’ve always got that bit more in your legs, there’s a been a couple of times (but literally only a couple) of times where I’ve wanted a marginally lower gear while racing. 5th time up the climb out of Medusa’s at Dalby was one!

(Mr MC posting)

Do people with digital scales understand the difference between the terms precision and accuracy? I assume when youre that obsessive (and Ive been there it’s not a term meant disparagingly) you actually calibrate your scales?

njee20,

What ratio’s you running,no problem in xc mtb races ?

36t ring, 11-36 block.

It’s been fine 99% of the time. If I’d had one available I’d have used a lower gear at Dalby, on the first climb at Margam and towards the end of Mayhem. Saying that, I’ve not had to walk up any hills this year, so it got me through, just had to push a little harder than I’d have chosen to!

Cheers, will buy one of those exact frames for next season, so want one for ages and I think you can now get it frame only in the uk.

Dont wanna buy it with sram 10 speed, how much for a chain and cassette which would last maybe 3 big events!!!!!!

You mean a Top Fuel? They’re stupidly expensive frame only, I’d buy a whole bike and flog the bits you don’t want personally!

Dont wanna buy it with sram 10 speed, how much for a chain and cassette which would last maybe 3 big events!!!!!!

The XX cassette I had last year lasted very well, stupidly expensive, but better durability than an XTR. The jockey wheels were rubbish, and I’d not bother to pay for the groupset as a whole, but I’d not shy away from the transmission parts myself. Shifting is obviously personal, I prefer the XTR, and anyone who prefer Avid brakes to the new XTRs is probably on crack 🙂

The XX cassette I had last year lasted very well, stupidly expensive, but better durability than an XTR.

Well that’s a right pile of tosh!

XTR cassettes last a year on my race bike, then spend six months on my training bike. Giles Drake went through two XX cassettes last year, and Steve Deas destroyed his in two races (fair enough they were Tour De Ben Nevis and Strathpuffer, but still).

Not IME, I used my XX cassette all year, then stuck a new chain on it when I sold the bike and it was fine – never done that with an XTR cassette.

They’re still far too expensive, but mine did appear to last well. The chainrings and jockeys on the other hand definitely didn’t last!

Looking at Breams Anthem 29er, thought I’d weigh my FS 29er.No digital scales so only a rough estimate.I stood on the scales at 80 kg picked bike up,90 kg,so bike weighs 10kg or there abouts.
Frame SC Tallboy
Forks Fox float 29 120(2012 model)
RP23 Boost Valve
xtr drivetrain
Hope x2 brakes
Hope hoops 29 with Crests
Thomson,Chris King and Easton carbon bits.
Shimano 959 spds.
maxxis Aspen kevlar tyres ran tubeless.

Looking at Breams Anthem 29er, thought I’d weigh my FS 29er.No digital scales so only a rough estimate.I stood on the scales at 80 kg picked bike up,90 kg,so bike weighs 10kg or there abouts.

Probably somewhere between 8kg and 12kg 🙂

@b r, if breams scales are right I suspect [*]mines between 10 and 11 kg. Mine has lighter frame,forks and much lighter non ust guess,but slightly heavier finishing kit.

(Mr MC posting)

Do people with digital scales understand the difference between the terms precision and accuracy? I assume when youre that obsessive (and Ive been there it’s not a term meant disparagingly) you actually calibrate your scales?

This – even those alpine scales that are recommended are +/- 5% accurate when leaving the factory, which is a hideous margin of error.

Mmm. Guess should say tyres.predictive text error!

grtdkad, mine was 20.something on the bathroom scales, though probably a little heavier at the moment.

SLR kit carbonio flow
EC90 post / SL bars
Rotor S2 (cracked !) now running an EA90
Marta mags
Carbon double chainset
SID WCs

Now I’ve seen njee20’s FS at sub 20lb I know what can be done.
I may just have a rummage in the garage and dig out a pair of Rocket Rons or Fast Freds that are lurking in there.

Currently building up a second HT frame too so will be on the look for a wheelset too. Ta!

Nice 19 Crell !

The scales I borrowed from a friend are accurate to within 0.01%, accordinging to the manufacturer Berkley TEC.

I’ve popped a couple of good quality weights on mine, and they’ve been spot on (+/- 5g which is as accurate as they go), which is more than can be said for our reasonably expensive Salter kitchen scales 😕

For me it nice to have a comparison as much as anything. Even if my bike is actually 10lbs heavier than my scales show it’s still lighter than my last bike! I’ve certainly seem some seriously optimistic scales, and weighed bikes that people were expecting to be several pounds lighter, but no one’s gonna put their hand up and say “this weighs 3lbs, but my scales are wrong, so it’s probably 25lbs”.

So, I have fitted a Rocket Ron with a Continental Supersonic tube (100g) and weighed again. Now 22lbs and plenty more to go at before thinking about a new wheelset (that UST RRalph on the back for a start!).
Thanks chaps!