GT grade Carbon Elite - reducing weight

[Konstantin]

Hello everyone,

I have been reading through the forums from time to time. Now, I eventually registered as I was hoping to get some feedback from you on how I could improve my bike weightwise for road use.

I am riding a GT Grade Carbon Elite (2020). In stock configuration, the bike is rather heavy (~ 9,85kg without pedals, bags etc). However, during the last year, I have upgraded a number of parts and reduced the weight to ~7,80kg in road configuration (without pedals, bags etc.). The bike is used as a road bike and a gravel bike with two wheelsets (aluminum for gravel; carbon for road). The main use case is road at the moment.

I have installed the following upgrades (weight in brackets is the new component weight):

Saddle: Fabric Scoop -> Aliante R1 (~185g)
Seatpost: GT aluminum -> XLC Sp001 aluminium 300mm (~221g)
Crank: FSA Adventure Omega 46/30 -> FSA SL-K 386 EVO 46/30 + PF30 Spacer (~655g)
Cassette: Tiagra 11-34 -> CS-M771 11-34 (~316g w lockring)
Rims: Stock disc WTB -> Carbon Clincher 45mm Disc (~1400g; wheelset w tire band)
Tires: WTB Riddler 37c -> GP5000 Tube 28c (~250g per piece)
Tubes: Butyl -> Latex (~85g per piece)
Discs: SM-RT30 -> SM-MT 900 (~111g per piece w lockring)

At the moment I am looking for a used GRX RD RX 810 or Ultegra RD RX 800 rear derailleur with cluctch system, which should also work with my Tiagra STIs (unofficially). This would also save a few grams (~30g) over my Tiagra RD, but I am mainly interested to swap because of the clutch mechanism.

In addition to that, going 11-speed would also be an option, if I would be able to find a good deal for a used Ultegra r8000 hydro groupset or grx 800 (STI, FD, RD for up to 34 or GRX RD RX 810, existing 4770 brake calipers should be compatible). However, from a weight perspective, this would probably only relate to ~100g in weight saving (mainly STIs and RD; have not yet assessed 11x cassette/chain, but probably neglectable). I would assume that the swap would cost me around EUR 300,00 - 400,00 in parts, if I would be able to find used parts (at least the STIs). However, I am not relly keen on swapping the groupset, as the weight saving seems to pretty minor compared to the hassle of finding used parts, the parts costs and getting them installed properly by myself (which may require me to invest in additional tools, small parts, fluids etc. + not 100% sure that I am skillful enough to install myself).

I was also looking into new handlebars for weight saving (and may be more compliance?). However, I am not quite sure what to expect in terms of weight saving, as I dont have a clue on how much the stock Droptune RS handelbars weighs (the higher specced variants of the Grade feature the Droptune RS superlight, so I assume, there should be some weight saving potential). The carbon bars I found in shops weigh in around 180g to 230g (42cm). Those bars can also be found used at (for me) more reasonable price points (though, I have not really made up my mind if I should buy a used carbon handlebar). If weight saving would not be substantial, I could hardly justify an investment in new handlebars, as the current aluminium handelbars work fine for me (might look into a shorter stem though).

For the sake of completeness: Ride ready, my bike is equipped with rather heavy crank brothers pedals (~ 400g; eggbeater and flat pedal combination; I may go for assiomas/vector3s in the future); top tube bag (w tire pump, snacks etc. weight varies); saddle bag (tire levers, spare tube, tools; ~ 200g), lights (~ 100g); 2x bottle cages (probably ~ 80g) and water bottles. An out front mount for a garmin fenix watch may be added in the future (~40g?).

Any suggestions on what I should focus next for weight saving ("most bang for the buck")? Recommendations for specific parts would be very much appreciated.

Thanks!

[bobrayner]

Pedals might be a good place to start, but you won't make huge weight savings. Xpedo M-force and CXR pedals are quite popular on this forum (200-300g) although in the past I've had a quixotic preference for Ritchey WCS Micro Road (208g).

I have heard that there can be variations in the weight of cleats - it may only be a few g, but if you have a different OEM's cleats lurking at the bottom of the toolbox, that could be a better cost:weight ratio than most upgrades. Maybe your preferred shoe makes a difference too!

Two big bottles plus cages plus the actual drink can be almost 2kg - how much liquid do you need to carry around in real-world conditions?

Could it be possible to consolidate the two bags into one?

[saldegracia]

You'll definitely be able to save some weight on stem/handlebars. For road use you could consider going narrower. A decent 40cm alu road bar should be around 250g, less for carbon. Problem with carbon bars is that they're often the first thing to hit the ground in a crash...

[bobrayner]

Also: Shoes!

My cheap road shoes (with 2-bolt cleats) are 152g lighter than my expensive Fizik XC shoes. So, if you're riding in an event where you won't have to put your feet down often (forestry roads, not muddy berms), maybe road shoes could be a cost-effective way to lose weight?

[Konstantin]

Thanks for your Feedback! Will definetely look further into pedals/shoes and the stem/bars. But the other things you have mentioned are also intersting, though, the potential gains seem to marginal .

[Konstantin]

Just a quick update. I got a good deal on carbon handlebars so I replaced the aluminium stock handlerbars. Weight saving in total is around 130g.

GT Droptune RS 40cm: ~310g
Stock handlebar tape: ~ 80g (~40g each)
Stock bar end plugs: ~20g (~10g each)
Total: ~410g

New carbon handlebar 40cm: ~ 204g
Tape: ~ 4g
Reused stock handlebar tape: ~ 68g (total)
New bar end plugs: ~4g (total)
Total: ~280g