Building a lightweight bike

[redcard]

Been messing around on Ribble for a few days, trying to plan a 7KG-ish build based around the R872 / Stealth frame.

First problem is I'm not a massive stealth fan, but if I can get a bike light enough within budget I'm willing to compromise.

I've been told the default build for this frame is around 8.5KG.

I'm probably going to set up a spreadsheet showing a number of combinations and weight savings. Ribble don't give weights for all components so this may be a bit time consuming and frustrating!

Bike must be Di2, decent wheels (club class, not necessarily race class).

Can anyone recommend best bang for the buck components? I get the £1 per 1g thing, but there must be some bargainous exceptions out there!
Would Ribble be open for sourcing any components not listed in their bike builder?
Can you recommend any alternatives? I was looking at a 2012 Foil but the last one I was tracking has went out of stock. Budget is £2.5K, possibly stretching towards £3K, and I'll probably be buying April / May so probably rules out any limited stock 2012s.

 

[fossyant]

Ribble has a new carbon frame out shortly- one up on the R872

The reason the default builds are heavy is they do have to scrimp on some components. Bars/stem - I'd recommend Ritchey WCS alloy stuff - it's almost as light as the carbon version, but stiffer - Ribble do stock Deda Zero which is nice and light.

Saddles and seatposts - another area of significant weight saving.

Wheels and tyres where you can easily shed 0.5kg without too much expense.

 

[redcard]

I was looking at the WCS finishing kit - seems decent value, plus it would all match.

Currently thinking of Ultegra wheelset to leave me a bit more for other components.

I thought the R872 only came out mid/late 2012..

 

[accountantpete]

I think the 8.5kg quote is a bit misleading. If you put on some really rubbish kit you might be there but any decent kit is going to take you below that figure.

The frame is approx 1000g which is about as light as you can get without paying big money.

Go full carbon forks, 1600g wheels and a good Hollowtech chainset and you are going to be around 7kg with reasonable finishing kit..

The rest of the kit can be made lighter but at great cost - I wouldn't bother.

 

[redcard]

The 8.5kg is what I was quoted for the default build, ie. the cheapest available

 

[Rob3rt]

Agree ^^

My aluminium bike is sub 8kg (I think, based on a me on the scales, then me and the bike on the scales measurement) and that is with my knockabout wheels (Fulcrum Racing 7's), heavy ass QR skewers and a boat anchor of a saddle.

 

[redcard]

Just done some workings on Excel. I can save just under 1KG , buying mostly mid-price components. Can't find a weight for the Sora groupset, but imagine Di2 is a saving of around 500g based on various figures I've seen floating round. RS80 24mms seem to be the best value wheelset at 1.5KG, so pretty close to the 7KG mark, with the bike coming in at £2,560

 

[Lee_M]

not saying you're wrong but if you have di2 dont forget to add the additional wieght of the battery.

You could of course save a fortune by losing a couple of kg yourself - unless you are built like Chris Froome!

Should also say my 62cm Trek Domane is around that weight - and I didnt have to do any messing about - just picked it up at the shop

 

[accountantpete]

You may care to spend an hour or so perusing the Weight-Weenies site.

http://weightweenies.starbike.com/listings/components.php?type=cranksets

there are weights for just about everything and a forum too.

 

[Lee_M]

agree with Pete, the following thread shows how picky they can get - but it also shows a weight breakdown of some coponents that might help you

http://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=105763

 

[redcard]

You may care to spend an hour or so perusing the Weight-Weenies site.

http://weightweenies.starbike.com/listings/components.php?type=cranksets

Was looking at that earlier - doesn't appear to have been updated in a few years, so not much of it is still relevant. Thanks for the link link though

 

[redcard]

not saying you're wrong but if you have di2 dont forget to add the additional wieght of the battery.

You could of course save a fortune by losing a couple of kg yourself - unless you are built like Chris Froome!

Should also say my 62cm Trek Domane is around that weight - and I didnt have to do any messing about - just picked it up at the shop

Think I've accounted for the battery, though no idea how accurate my guess is.

I'm around 70kg so not much I can lose. I live on the 3rd floor and our flat isn't the biggest so the lighter the bike the less hassle there will be storing it and moving it around. Plus I just want a fancy, light bike!

Anyway, I won't be messing about with the bits - Ribble will sort that side out

What model Trek do you have?

 

[Lee_M]

Think I've accounted for the battery, though no idea how accurate my guess is.

I'm around 70kg so not much I can lose. I live on the 3rd floor and our flat isn't the biggest so the lighter the bike the less hassle there will be storing it and moving it around. Plus I just want a fancy, light bike!

Anyway, I won't be messing about with the bits - Ribble will sort that side out

What model Trek do you have?

I have the domane 5.2 - big bugger though at 62 cm, but heaviest things on it are:

me
my saddle pack

 

[accountantpete]

Here's my est

Bars,seatpin, saddle, cabling and headset 1000g
Wheels and tyres 2200g
Frame and Forks 1500g
2011 105 Groupset inc pedals 3300g


7000g

 

[dan_bo]

You're putting Di2 and nice wheels on a sodding dribble?

The world's gone maaaaaad!