how to build the lightest hardtail mountain bike...

[OneDs]

rhinochopig said:

missed that requirement. In my defence discs are utterly pointless on a weight weenie bike. You'd pinchflat long before you ran out of v-brake stopping power.

I agree but our rims will not take v-brakes

http://www.ax-lightness.de/xist4c/web/AX---Premium...

bugger the rims mean we need tubular tires as well, oh FFS!

here you go 430g per tire 85 Euros http://www.bike24.com/p27904.html

Edited by OneDs on Wednesday 9th March 15:54

[mchammer89]

Real MTBers run singlespeeds...

[anonymous-user]

cant really suggest much. going tubeless will save a bit and schwable make some very light tyres.
road mechs are usually a bit lighter than mtb stuff, thats all i got!...

[rhinochopig]

pablo said:

cant really suggest much. going tubeless will save a bit and schwable make some very light tyres.
road mechs are usually a bit lighter than mtb stuff, thats all i got!...

I question the need for a full chain set TBH. My MTB hardtail runs a single front middle Ti ring and a widely spaced rear block. I have never needed any more than the 9 gears it offers even during a race. The reduced weight offsets the lack of lower gears too.

[Gooby]

mchammer89 said:

Real MTBers run singlespeeds...

http://www.youtube.com/watch?v=psNPZeqzuGo

[anonymous-user]

rhinochopig said:

pablo said:

cant really suggest much. going tubeless will save a bit and schwable make some very light tyres.
road mechs are usually a bit lighter than mtb stuff, thats all i got!...

I question the need for a full chain set TBH. My MTB hardtail runs a single front middle Ti ring and a widely spaced rear block. I have never needed any more than the 9 gears it offers even during a race. The reduced weight offsets the lack of lower gears too.

A 1 by 9 setup must be a huge weight saving on a triple front ring, seeing as you lose two chainrings, bolts, front mech, cable, shifter and some chain links.

Do you have some kind of front chain guide to keep the chain on the middle ring?

[AVeryNaughtyBoy]

So far then:

Frame: Scott Scale (Medium) - 899g

Forks: Air-Way 89SSV Full Carbon - 1,140g

Wheels: AX Lightness Premium - 995g (Pair)

Brakes: Magura Marta SL Magnesium with Featherlight Rotors - 315g (Pair??)

Total: 3,349g

Please update this as other items are found and agreed.

[Vladimir]

Think my tyres (1.8" Nobby Nics) are 470g each but they last AGES and grip really well too. Did try thinner inner tubes but they were terrible. A weight weenie step too far.

I wonder how low you could go? Sub 16lbs?

Mines a bit under 22lbs and feels pretty light but it's sensibly specced.

[Roman]

A handy benchmark for component weights taken from here:

http://weightweenies.starbike.com/articles.php?ID=...



Frame: Scott Scale Limited Large '05 1064 g
Fork: RockShox SID World Cup tuned 984 g
Headset: M2Racer w/ Schmolke cap 36 g
Stem: Extralite Ultrastem UL2 100mm 92 g
Stem Spacers: Carbon 4 g
Handlebar: Schmolke TLO 68 g
Grips: Procraft Superlite 8 g
Brake Lever: Extralite Ultralevers 64 g
Brakes: Steinbach with B-T-P Pads 154 g
Crankset: Storck Powerarms 316 g
Chainrings: MGM carbon 44x94, 29x94, 20x58 47 g
Chainring bolts: Extralite aluminium 12 g
Bottom Bracket: New Ultimate Scandium incl. bolts 122 g
Pedals: Crank Bros. Triple Ti 187 g
Shift Lever: Sachs Quarz tuned 115 g
F-Der: BTP Campagnolo 68 g
R-Der: BTP Carbon 103 g
Chain: Wippermann Titanium 222 g
Cassette: Steinbach 11-26 118 g
Wheelset: Soul Kozak, DT 1.5/1.8 spokes/nipples, Notubes ZTR rims, Ritchey rim tape 1173 g
Tubes: Continental Supersonic Race 26" 90 g
Tires: Maxxis Maxxlite 310 597 g
QR: Tune Skyline time trial skewers 17 g
Seatpost: Schmolke TLO 31.6 x 300mm w/ shim 105 g
Seatpost clamp: Scott aluminium 14 g
Saddle: Tune Concorde 45 g
Cables and Housing: Magura/Power-Cordz/Tune 57 g
Total: 5878g

[itsnotarace]

Vladimir said:

I wonder how low you could go? Sub 16lbs?

This one is 11.28 lbs / 5120g

http://www.fotos.light-bikes.de/main.php?g2_itemId...

[itsnotarace]

The one Roman posted is the same bike, but updated in my link above.

[rhinochopig]

el stovey said:

A 1 by 9 setup must be a huge weight saving on a triple front ring, seeing as you lose two chainrings, bolts, front mech, cable, shifter and some chain links.

Do you have some kind of front chain guide to keep the chain on the middle ring?

No need. Just shorten the chain slightly, and be sensible with shifting, i.e. Not crashing through the gears in one go when you get to a hill. I also run on bigger gears on downhills to tighten the chain to avoid bounce - although I do this on my full sus anyway, so no change really.

I tried a SS and just couldn't get on with it on my local route - the hills are too steep - so thought this was the next best thing to try. The beauty is that if you run a Ti middle, it'll last for ever as you just keep flipping it to ensure even tooth wear.

Give it a try if you have a hardtail - you won't go back.

[Vladimir]

itsnotarace said:

This one is 11.28 lbs / 5120g

http://www.fotos.light-bikes.de/main.php?g2_itemId...

WOW!

[Roman]

itsnotarace said:

Vladimir said:

I wonder how low you could go? Sub 16lbs?

This one is 11.28 lbs / 5120g

http://www.fotos.light-bikes.de/main.php?g2_itemId...

Great!

For a weight weenie build I'd just go for 1x10 gearing.

A hardtail I built manages fine with a single 36t chainring and 11-34 cassette and that weighs around 9kg/20lb (cost around £350 to build).

A 5kg bike would have no problem at all climbing with similar or even slightly higher gearing such as a 38t chainring and 11-36 10sp cassette. On a normal bike going 1x9 saves nearly 400g but with superlight components would probably save nearer 200g.

Dedicated single chainrings tend to have taller teeth to help prevent the chain from bouncing off on rough descents.

[rhinochopig]

Roman said:

Great!

For a weight weenie build I'd just go for 1x10 gearing.

A hardtail I built manages fine with a single 36t chainring and 11-34 cassette and that weighs around 9kg/20lb (cost around £350 to build).

A 5kg bike would have no problem at all climbing with similar or even slightly higher gearing such as a 38t chainring and 11-36 10sp cassette. On a normal bike going 1x9 saves nearly 400g but with superlight components would probably save nearer 200g.

Dedicated single chainrings tend to have taller teeth to help prevent the chain from bouncing off on rough descents.

10 speed chains aren't up to the job on an MTB IMO. If you're a bruiser when it comes to climbs they tend to snap IME.

[itsnotarace]

That 5120g bike could obviously lose another 134g if they went for the Scott 899g frame instead, the current frame weight on that Scale Ltd build is 1033

Current wheelset is 1017g as well. So swapping to the AX lightness tubular set would save another 22g

Net result would be 4964g or 10.94lbs

Will have another look through the spec to see if any other potential savings could be made

[itsnotarace]

Could drop another few grams on the saddle/seatpost by swapping from

Seat: M2 Racer 42
Seatpost: Schmolke TLO w. Shim 105

Total = 147g

to

http://www.poshbikes.com/product.php?id=265

Saddle/seatpost combined 110g

So another 37g savings there

New total 4927g / 10.86 lbs

[itsnotarace]

Swap

Pedals: M2 racer ORB 2 90

for

http://www.poshbikes.com/product.php?id=343

74g

another 16g saved

Total now: 4911g / 10.82 lbs

[mk1fan]

I would break any of those bikes in one ride!

Grace, smoothness and control are not things associated with my riding style.

[village idiot]

there is a reason for all this...

i'm trying to get my 23.8lb cannondale f900sl down to 20lbs... i plan to do this by fitting a set of hope/stans wheels with tubeless nobbly nics, a set of rockhox sids (2nd hand the next time they come up on singletrackworld classifieds) and a flite saddle...

i'm also helping a mate out shopping for something nice and light. the current choice is this little lovely:-

http://www.farnhamcycles.co.uk/Shop/p/217-merida-o...

for £2k i doubt you would get better... it is the xc world cup winning carbon frame (930g i think)... not sure what it weighs, but it must be sub 20lbs as the equivalent full suspension version is a 20lbs bike!!!

http://www.farnhamcycles.co.uk/Shop/p/746-merida-n...