Where is the weight coming from ? Advice Appreciated

jmillen

Evening people...

I wonder if you could help me please. For one reason or another, I'm turning into a bit of a weight saving freak. Could you help shed some light onto where the weight in my bike is coming from? What are the main areas I could "improve" to get a decent weight reduction. I've put ** next to the main ones I think may have potential for a good saving, but I'm from far knowledgeable in these things :lol Suggestions for replacements would be much appreciated.

Spec as follows:

Frame: Standard Boardman Pro HT 2009
Forks: Rockshox Reba Race 2009
Bars: Ritchey WCS Carbon
Stem: Ritchey WCS Carbon
Seat Post: Ritchey WCS Carbon
Shifters: SRAM X0
Rear Mech: SRAM X0
Front Mech: SRAM X9

Grips: Lizard Skins Peaty (White)
Brakes: Avid Elixir R Carbon with 185mm rotors front and rear

Chainset & BB: Truvativ Stylo GXP **
Cassette: SRAM PG950 **
Rims: Ritchey WCS **
Tyres: Schwalbe Nobby Nic

Can try and provide more info if anyone needs it, thanks in advance

GHill

How much does the bike weigh? What is your aim for it to weigh? What's the budget?

You've certainly pinpointed the possible main offenders. How about an XT cassette to replace the PG950? Seems a relatively cheap way to remove some rotational weight.

Any idea what hubs and/or spokes? Can you weigh the wheels?

nicklouse

what are the hubs?

cranks will cost a lot to lose much.

what is the current weight?

jmillen

Using a very scientific (...not) method i.e luggage scales, I think its about 25lbs at the moment...In terms of how much I'd like it to be....haven't really thought about it. As light as possible without spending silly amounts of money.

I've just been looking at a PG990 cassette, how does that compare to the XT ?

As for budget....undecided It depends on what kind of saving the ££ will bring and if I feel its justified. I'm going to assume the wheels could cost the most to replace with lighter versions?

jmillen

I'll pop out to the garage now and see if I can see what the hubs are. If not, I'll take the front wheel off and come in and weigh it...I'll be right with you...

Northwind

Take it all to bits and weigh it, only way to really know. Bars, stems etc can turn out to be heavier than you'd think. I'd be looking at the wheels myself.

bamba

how about changing the rear 185 rotor for a 165 ? not much but would not cost a lot, could even change the front if your that bothered

ilovedirt

wheels are pretty heavy generally

ravey1981

Wheels are where excess weight can make the most difference. But go too lightweight and you lose durability. To be honest with you I'd stop where you are. 25lb is a respectable weight for a trail hardtail.

Lose a few pounds yourself*, its free and you'll feel the benefits more than spending a couple of hundred quid to save a pound (which realistically is all you have left to gain)

*No offence

warrerj

Wheels and cassette would be my first bet. As as said above go too light on weehls and you'll be forever rebuilding them.

for all your weight info try here :

http://weightweenies.starbike.com/

BlackSpur

The wheels are pretty light, i remember reading somewhere about 1800g? You'd have to spend a fair packet to get something significantly lighter than that.

GHill

jmillen wrote:

I've just been looking at a PG990 cassette, how does that compare to the XT ?

XT 11-34 is 298 g, PG-990 (11-34) is 305 g. For reference, a PG950 is 452 g. If you're happy with a 11-32 cassette you can save even more, but I personally don't like those ratios.

All weights sourced from the weight weenies website.

jmillen

Seems Blackspur is about right. Front wheel weighs approximately 4lbs and confirmed weight of bike on some digital scales as about 25lbs (give or take due to me balancing it on there).

BlackSpur

jmillen wrote:

Seems Blackspur is about right. Front wheel weighs approximately 4lbs and confirmed weight of bike on some digital scales as about 25lbs (give or take due to me balancing it on there).

1800g is for a pair, without tyres, tubes, rim tape, disc rotors and QR skewers.

jmillen

Coincidence that the front wheel with tyre and all the rest weighs about that

ilovedirt

well, unless you're a big lad, you don't need 185mm rotors front and back, 160 on the back should do you, and 160 front as well maybe, i find that to be fine on my AM bike.

jmillen

Nope, not a big lad, you're right, 160mm discs would be fine front and back, I just liked the look of the big discs....

I know it all adds up, but will going back to 160mm rotor really make that much difference?

I can see with the change of cassette and pedals, I should be able to save a couple of hundred grams at least. As mentioned in a previous thread, I need a new BB anyway, so seems like a good time to get a new chainset whilst I'm there.

I was looking at carbon ones, but they don't seem to be as light as I thought they were going to be for the money :?

BlackSpur

Don't bother with rotors, the extra stopping power is worth the small weight penalty. What pedals do you have currently?
The Stylo is a pretty decent, fairly light chainset.
The issue you have is that you bought a bike with a very well rounded spec - everything is 'pretty light' with no obvious weaknesses to the overall spec. Losing weight will be difficult, your best bet is to save up a big wad of cash and do something big i.e. a set of race-weight wheels.

ilovedirt

jmillen wrote:

I know it all adds up, but will going back to 160mm rotor really make that much difference?

well it's the same with everything isn't it? personally i'd be fairly happy with 25lbs

is the reba race coil or air? you could get an air one if it's not already, would save you a little bit.

BlackSpur

All Reabs are air

jmillen

Yeah. they're air

I'm looking at a Raceface Deus XC Chainset (just an option at the moment) with what ever BB it comes with. As for pedals, they look like V8 replicas. Tempted by some MG1's to replace them.

BlackSpur

I'd definitely whack some MG1s on, that'll same you at least 100g i'd think.

Northwind

It doesn't look like the stylo's worth replacing, it's a good crank. Depends on the exact model/spec though, which is why I reckon you should weigh it all, sometimes things aren't quite what you expect.

Switching to a 160 rotor won't reduce much weight at all, an Ashima Air 160mm is 85g apparently, compared to 112g for their 180mm, or 140-150g for a typical one. So not a huge amount. But then, that's about the difference between a light bar and an average bar, so not to be sniffed at either. I doubt very much that you'll miss the power, my 160mm rear's never failed to stop me, I run out of tyre before I run out of brake.

Torres

What about the frame? Not sure exactly what the CB frmes come in at, but i'd wager a carbon frame would bring the total weight down a fair bit.... if you're feeling flush...

jmillen

Thats next years plan

I'll have about £2k to spend on a hardtail then hopefully, but for now, I just want to get this one as low as I can.

I'm thinking cassette & MG1's for now, followed by new chainset and BB soon

bails87

I think it was Jeast who weighed the wheels on his HT Pro, they were around 1700g. The chainset weighs about the same as an XT one. The only obvious upgrade potential (I've got an '08 Pro myself) is the cassette. Everything else is pretty high end already, without getting into ridiculous money.

The Northern Monkey

Sell the boardman and buy a different bike. It'll probably be cheaper.

cougie

25lb is >11kg.

You really wont notice any difference taking a couple of 100gs of the bike.

A 500ml waterbottle is 500g. Can you tell if the bottle is empty or not on your bike ?

If not - save your money.

supersonic

Wheels or frame.