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Having ridden a 3x mtb for quite a while (well over 5 years....) I'm on the market for a gravel/cx one.

I tried some and, while I'm definitely after a light carbon frame bike, the biggest difference I noticed came from the gears. And here's the point: as I understand it, many a road bike have a 52-36 crankset and 11-28 cassette. This gives you a ratio of 4.72/1.28 which in gear/inches translates as 35.8-132.16 ({Gear/Inches} =wheel diameter in inches X n° of teeth in front chainring divided by n° of teeth in rear sprocket}}...if I understand it right. Great for speeding, not so when climbing (I live in the South of France and climbing cannot be avoided).

I noticed that, for example (similar price bracket):

1)The lovely White Essex One has a: 44 (1x) & 10-42cassette= 4.4/1.04 , i.e. gear/inches:  29.2 - 123.2

2)The new Giant Revolt Advanced2: 48-32   & 11-34cassette = 4.36/0.94, i.e. gear/inches: 26.3- 122.1 

3)The new Orro Terra C Adventure:   48-32       11-30                  = 4.36/1.06                                    29.7- 122.1

and so on...

Am I doing it right? Because from this it appears that, for ex, the n°2 climbs more easily and it is not that much "slower" when speeding.. 

Basically: can anyone advise on a carbon frame bike, in this price bracket, that I can (also) take offroad on steep paths but that would allow me to keep up with my friends on road bikes....?

For reference, my old Giant 3x mtb: 42-22         11-30                 = 3.81/0.73                                    19 - 99.1 (insanely easy for climbing but makes me pedal like crazy when speeding on flat asphalt road...!!).

Any comment would be appreciated!

 

Huck.

43 comments

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cyclesteffer [379 posts] 3 months ago
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Not ridden the Giant, but mates have the Orro and Whyte and they keep up absolutely no problem with road bikes. It's all about the legs , heart, lungs and fitness. Tuck in and get low on the bars on the downhills and you'll be fine.

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CXR94Di2 [2510 posts] 3 months ago
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A few questions, how old, weight, how fast a speed you can maintain?   

here are some speed figures in MPH for different gear ratios for my road bike, it uses a triple crankset 48/36/26. Ive included rpm/cadence

 

   rpm    80       85      90       95      100     105     110

26x40   4.07    4.32   4.58   4.83     5.09    5.34    5.59 ---  (min gearing mountains)

26x32   5.07    5.39   5.70    6.02    6.34   6.65    6.97

36x12  18.78  19.95  21.12  22.30  23.47 24.65  25.82

48x11  27.29   29.00 30.70  32.41  34.11 35.82  37.52

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Griff500 [348 posts] 3 months ago
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You don't mention tyres. I moved from MTB to road 5 years ago, and coincidentally live in the South of France. I found that the simple act of moving from knobbly tyres to slicks made a huge difference in ability to make rapid progress on the road. I don't however use tyres on the road which I would also want to use on gravel. (I am on 25mm GP4000).

In terms of gearing, I am on the 52-36, 11-28 setup you quote, and at the age of 60, that will get me up any hill I am likely to encounter, including Ventoux (or some shorter, hills of close to 20%), at a fairly decent speed. When it comes to cassette replacement however, I will probably go to 11-30 next time. But to be honest, any lower than that 11-32, or anything less than 50-34 front, and you aint going to keep up with your friends on road bikes as you put it. 

 

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AKH [64 posts] 3 months ago
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This is by far the best gear calculator I've found online. I particularly like the visuals and the option to compare two setups.

 

http://www.gear-calculator.com/

 

When it comes to going uphill, the power required is a function of your mass, the slope, and the speed you go up it (basically what's your vertical speed and mass). You can drop into a lower gear, which will mean you can increase your cadence to a (more) comfortable level, but if your friends are simply way lighter or more powerful riders, it won't help. It might be easier to maintain a certain power at 90 rpm than say 50 rpm, but the power to get you up 500m of climbing in X number of minutes is the same.

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CXR94Di2 [2510 posts] 3 months ago
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 or anything less than 50-34 front, and you aint going to keep up with your friends on road bikes as you put it. 

How fast do you think he needs to go.  Once over 30mph on a descent, you're in comfortable freewheeling territory. If you want to push the speed along then, 100 rpm on a 48-11 is 35mph, remember freewheeling  1

If you want to to go very fast, which takes huge amount of power and cadence-remember going downhill freewheeling. 48*11 @145rpm is ~51mph- I know, I achieved this in Tenerife albeit very briefly:D

 

So speed comparison for you to ponder @100 rpm(lets say slight decline or flat terrain)

48*11=34.3mph

50*11=35.8mph

53*11=37.9mph

3.6mph difference

I know I cant sustain 32mph on a flat road on a normal road bike, I have 300W +FTP

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rdmp2 [65 posts] 3 months ago
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Most road bikes are over geared. Honestly how often are you pedalling hard in 50x11? A road /cx/gravel bike will be faster than your mtb as it will give a more aerodynamic position (for flat /down) and maybe lighter weight (for going up). Also faster tyres, although your mtb could take these also. My gravel bike with 48/32 11-32 gearing and semi slicks has no trouble keeping up with my roadie friends (unless your friends are racers)

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Griff500 [348 posts] 3 months ago
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CXR94Di2 wrote:

 or anything less than 50-34 front, and you aint going to keep up with your friends on road bikes as you put it. 

How fast do you think he needs to go.  Once over 30mph on a descent, you're in comfortable freewheeling territory. If you want to push the speed along then, 100 rpm on a 48-11 is 35mph, remember freewheeling  1

 

Presumably fast enough to keep up with his mates. All I can do is speak from experience. Granted, I am a below average cadence rider, being much happier grinding up a hill at 75rpm than at 100. My area (The Vaucluse), is characterised by long grinding ascents followed by long sweeping descents. Despite my age (60), I set upper quartile Strava times on those long climbs and wait for my mates at the top, and lower quartile times on descents where we are all spinning out and they wait for me at the bottom! "Once over 30mph on a descent, you're in comfortable freewheeling territory" - no you're not on a 3% descent. eg Gorge de la Nesque, 15km @ 2,5% average. If I had a higher gear than 52/11 I'd use it.

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Huckfinn [39 posts] 3 months ago
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Wow!

Thank you all for the feedback!!

Now, in good order, starting from the last comment:

@rdmp2: A cx/gravel will certainly be lighter than my 13kg mtb! 48/32, 11/32 seems fine to me when with my "roadie friends". But I also like to take detours offroad & uphill and leave them on the tarmac. And here's when I would need an 11/34 (or more)....

@CXR94Di2 : again, 48/11 sounds fine. But what cassette do I pair the 48 with (as per above..?)

@AKH : I'll have a very good look at your calculator tonight when back from work. So far never had problem keeping up with roadies uphill (I'm actually often ahead of the pack).. With my mtb , downhill is the tricky part...

@Griff500: I'm almost your age. (Where do you live exactly..? I'm in Beausoleil) I currently use semi-slicks. As I said I think 48-11 is fine. Obviously 50-11 would be better. The problem is finding a bike (cx or gravel, doesn't matter how you call them) that allows me to climb almost as well as with my mtb. Can't be "as well", of course, 'cause I also have 26" wheels, so basically that's the reason I can go as low as 19 gear/inches. By the way, I never need to go this low...

@CXR94Di2 : I'm 59, 186cm, 75kg.

I come from a corner of Northern Italy where almost everybody (young, old, male or female) uses a bike. For me cycling is second nature. As a result I can keep up with/stay ahead of on my 26" mtb much younger cyclists on fancy carbon road bikes.... No issue there. But simply, as I'm looking for a new bike, my thoughts were of getting something that would allow me to do both on road (80%) and off. I'm not expecting to find one as "fast" on road and at the same time as "agile" off as a road/mtb one....... BUT: which bike would get me the closest? The Orro, the Whyte, the Revolt....? Any other model?

 

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Griff500 [348 posts] 3 months ago
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Huckfinn wrote:

 

@Griff500: I'm almost your age. (Where do you live exactly..? I'm in Beausoleil)

The Luberon. (A long way from you)

 

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CXR94Di2 [2510 posts] 3 months ago
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Once over 30mph on a descent, you're in comfortable freewheeling territory" - no you're not on a 3% descent. eg Gorge de la Nesque, 15km @ 2,5% average. If I had a higher gear than 52/11 I'd use it.

Ive ridden Gorge de la Nesque both ways.  The desecnt is not super fast because of lots of blind bends, until the latter part where it staightens outs a bit.  I descended on my bike which had 42 outer ring and was able to keep up with compact chainset riders, albeit I was using a higher cadence.  Now with my 48 outer chainring, I out run most riders with compacts, being a bigger rider. 

 

@Huckfin  I use a 11/32 for general riding and when I go to the mountains I use 11-40.  Im a heavyweight rider@95KG.  My preferred method to ride is spinning usually above 90rpm even on alpine climbs like Ventoux etc.

 

 

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Griff500 [348 posts] 3 months ago
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CXR94Di2 wrote:

Once over 30mph on a descent, you're in comfortable freewheeling territory" - no you're not on a 3% descent. eg Gorge de la Nesque, 15km @ 2,5% average. If I had a higher gear than 52/11 I'd use it.

Ive ridden Gorge de la Nesque both ways.  The desecnt is not super fast because of lots of blind bends, until the latter part where it staightens outs a bit. 

La  Nesque is my back yard. From the viewpoint on the North side, travelling West down to Auzon, there are only a couple of blind bends, for much of the route you can see the road snaking down the valley ahead of you. The South side is more twisty.

Notwisthstanding that, your comment "once over 30mph on a descent, you're in comfortable freewheeling territory" doesn't make sense on long shallow gradients.  If you can generate power through the crank at 110 rpm, that's fine. I can't.  

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alansmurphy [2113 posts] 3 months ago
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I'm also of the camp that doesn't put too much weight on the 53/11 gearing. How much of our cycling life do we spend spinning out, i'd suggest not much. Having closer ratios in the middle of the cog and the more comfortable climbing gears will be much more efficient over a reasonably long ride...

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Daveyraveygravey [668 posts] 3 months ago
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alansmurphy wrote:

I'm also of the camp that doesn't put too much weight on the 53/11 gearing. How much of our cycling life do we spend spinning out, i'd suggest not much. Having closer ratios in the middle of the cog and the more comfortable climbing gears will be much more efficient over a reasonably long ride...

 

I don't think this argument stacks up, at least in my experience.  Let's go back to the good old days when all you had to choose was a standard or compact chainset, say 10 years ago! Whilst you have to be pretty far up the ability ladder to spin out a 53/11 regularly, a 50/11 is much easier to run out of gears with.  I'm not talking about screaming down a 20% slope at over 50 mph, I'm talking about maybe a 5% slope with a bit of tail wind.  Or a gentler slope but riding in a bunch; whenever I have ridden a compact I have been frustrated by running out of gears at speed more often than running out of gears climbing.  

I think the OP's question might be redundant though.  My cycling buddies all have road bikes, cx bikes and mtbs.  I don't have a cx, just a road bike and an mtb; I now won't go with them when they take the cx bikes out, because I have to take the mtb and I know I won't be able to keep up.  I'll try for 60 minutes or maybe 90, but at some point the greater effort required to move the mtb on a road or smooth off road trail will wear me out before them. It's a good challenge and workout initially but eventually you get tired.  I haven't tried the comparison of road bikes v cx bikes but I bet the road bike will require less effort than the cx bike for the same distance covered.

Road bikes are optimised to go fast on roads, they are (just) strong enough to take most potholes whilst being light, the tyres are just grippy enough in most conditions to keep you upright, whilst being light, the brakes are good enough to stop you whilst being light.  The gears are chosen to give you a compromise between getting up steep hills and maintaining a good average speed on the flat.  

MTBs are optimised for off roading, they aren't as light, the brakes are stronger, you sit in a different position, the wheels and tyres are heavier, wider, grippier.  The gears are much more biased to climbing in situations where you could have a lot less grip than a road bike.

CX/gravel/adventure bikes are a compromise between the two above. They can mix some road riding and some gravel riding, but at the extremes of either they just won't be as good.

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CXR94Di2 [2510 posts] 3 months ago
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Griff500 wrote:
CXR94Di2 wrote:

Once over 30mph on a descent, you're in comfortable freewheeling territory" - no you're not on a 3% descent. eg Gorge de la Nesque, 15km @ 2,5% average. If I had a higher gear than 52/11 I'd use it.

Ive ridden Gorge de la Nesque both ways.  The desecnt is not super fast because of lots of blind bends, until the latter part where it staightens outs a bit. 

La  Nesque is my back yard. From the viewpoint on the North side, travelling West down to Auzon, there are only a couple of blind bends, for much of the route you can see the road snaking down the valley ahead of you. The South side is more twisty.

Notwisthstanding that, your comment "once over 30mph on a descent, you're in comfortable freewheeling territory" doesn't make sense on long shallow gradients.  If you can generate power through the crank at 110 rpm, that's fine. I can't.  

 

Just checked my Gorge descent, the first 2 or 3 miles I hardly pedalled lots of zero cadence and average nearly 26 mph. I peaked at 35 mph @110rpm later on with  a 42t chainring.  I came in top 20% on Strava without even really trying.  It's worth saying again most folk dont need 48 or above chainrings.  Unless you are chasing KOM segments or racing, most folks are happy to top out less than 40 mph 

 

The faster guys in my group were 2 mins ahead 2mph average faster and came in the top 5% of descent, but we're riding very aggressively at pace into blind bends right from the start of the descent.  Whilst I arrived a little more safely  1

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Huckfinn [39 posts] 3 months ago
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@Daveyraveygravey: you put it right when you say "CX/gravel/adventure bikes are a compromise...... They can mix some road riding and some gravel riding, but at the extremes of either they just won't be as good."

I suspect the title of my post should have been more like "Trying to keep up with my friends on road bikes: which wide-tire bike could I buy". That could have made clearer I guess.

And by wide I mean 38 to 45c......, with discs, .....and low gears :-))))

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CXR94Di2 [2510 posts] 3 months ago
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Huckfinn wrote:

@Daveyraveygravey: you put it right when you say "CX/gravel/adventure bikes are a compromise...... They can mix some road riding and some gravel riding, but at the extremes of either they just won't be as good."

I suspect the title of my post should have been more like "Trying to keep up with my friends on road bikes: which wide-tire bike could I buy". That could have made clearer I guess.

And by wide I mean 38 to 45c......, with discs, .....and low gears :-))))

 

Have a look at the Boardman ADV 8.9 .It comes with 10 speed 11-32 Cass and 48/32 crankset.  It takes 40 mm tyres standard.  I would change the inner ring to 30t because FSA adventure crankset has also a 46/30 crank on the same BCD.   Then I would fit a 11-36 Cass, these are available in 10 speed.  

That would give you gear inches 21.96 to 115" .Is that enough range?

 

Boardman from Halfords plus discount if have vouchers and or British cycling membership

 

Only it's alloy frame, but it won't matter on 40 mm tyres, it will be Uber smooth

 

 

 

 

 

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rdmp2 [65 posts] 3 months ago
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Are you planning to just use one set of tyres or change depending on terrain? Only ask as a larger tyre increases the gearing slightly. 48x11 gearing with a 45c tyre is marginally bigger (practically equal to) 50x11 with a 25c tyre. Personally I think 48/32 chainset is fine for me but there aren't many options (and they aren't exactly aesthetically pleasing). Most long cage road mechs are now fine with a 34t sprocket so you can get 1:1 gearing with a compact chainset (albeit with some slightly larger jumps than from a tight cassette). IMHO anything much over 110 gear inches isn't worth it- I'd rather duck and tuck. But I have occasionally been grateful for my 28 gear inch low gear

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Huckfinn [39 posts] 3 months ago
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The Boardman looks lovely..pity it's not carbon!!

I had a look at the carbon ones but there doesn't seem to be any 2x

....

I'll use one set of tires, probably 38 or 40c.

48/32x11/34, or 50/36x10/42 I think would be absolutely perfect

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peted76 [1361 posts] 3 months ago
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Rose have a configurator.. and I hear good things about them.. 

https://www.rosebikes.co.uk/bikes/gravel

Also you can choose a 46/36 crank.. with an 11/34 rear cassette on.. that's about as good as it gets gravely/roady wise I reckon. 

 

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CXR94Di2 [2510 posts] 3 months ago
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FSA adventure crankset do 50/34 .48/32 46/30.  They use a threaded bottom bracket

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CXR94Di2 [2510 posts] 3 months ago
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 CX/gravel/adventure bike can do it all, if it has the right gearing and tyres.   I own a Kinesis Tripster titanium adventure bike.  It has wide tyre capacity, so I run 40 mm G Ones most of the time to do club rides, 100 mile sportives.  In this setup I can ride over 21mph solo for 10 miles, do 19 mph 70 mile club runs.  If I swap my wheels to the aero set, I have used the above bike >21 mph on closed road 80 mile sportives.  Then if I swap my wheels to mountain setup, I can ride up any climb at a high cadence because it has very low end gearing.  It's not the lightest or raciest geometry but the difference between a race bike and adventure bike isn't so great.  Just need to accept all the marketing about sub category bikes is bull-one bike can do most of it.

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Huckfinn [39 posts] 3 months ago
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....Any suggestion for a carbon framed one? 

By the way, thanks for the Rose suggestion Peted76.

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CXR94Di2 [2510 posts] 3 months ago
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Have you thought of building up a bike?   Get the frame, gearing, groupset and tyre clearance.

Here is a carbon frame bike,  it will need different groupset/BB and cassette to achieve gearing range you desire.  Its wide tyre and disc braked

Genesis Datum 10 2019 - Road Bike

 

https://www.youtube.com/watch?v=Lnxaq1dpKVc

 

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Huckfinn [39 posts] 3 months ago
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What a coincidence!!

That's exactly what I was looking at now!

Never built one myself, so finding websites who sell at reasonable prices components that I'm not 100% sure what are needed ....is tricky.

Of course, I need: 

1)a carbon frame and fork

2)a hydro groupset

3) quality wheels + handlebar

But what about all the bits and pieces............?

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CXR94Di2 [2510 posts] 3 months ago
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Ive edit my post to look at the Genesis bike

Your frame design dictates whether internal or external cable routing.  You have the option to think about electronic shifting Di2, costs rise alot.  I suggest you stick with 10 speed because of the available 11-36 cass to give climbing gears,  mated with a 48/32 crank

 

Just out of interest, why does the bike have to be carbon framed, when running large tyres?  

 

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kevvjj [463 posts] 3 months ago
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Huckfinn wrote:

....Any suggestion for a carbon framed one? 

By the way, thanks for the Rose suggestion Peted76.

Have a look at the GT Grade in carbon. Tyre size is limited to about 34c but a very capable bike on and off-road.

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rdmp2 [65 posts] 3 months ago
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Budget?

Trek Checkpoint?

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Huckfinn [39 posts] 3 months ago
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...."why does the bike have to be carbon framed...?"

1) weight                                                                                                                                                                                     2) whenever I tried an aluminium vs carbon (for ex: Giant TCX) I much preferred the second...

@kevvjj : Looks like quite a cool bike, thanks! Altough, for that price, I would prefer the (even heavier) Giant Revolt with a 48/32-11/34.

@rdmp2 : budget mid-2k euros. Thanks for the Checkpoint suggestion! that's also a good one!

One thing though: why are they all so "heavy"? I mean, following the suggestion from CXR94Di2 I stopped at my lbs this morning. They'd charge 150-200euros to install a bike. Basically I could buy a Cube Agree C:62 frame + fork, Ultegra or Sram 22, these wheels:                                 https://www.chainreactioncycles.com/fr/fr/roues-a-disque-prime-pro/rp-pr... or even:   https://www.lightbicycle.com/700C-V-shape-36mm-depth-hand-built-carbon-r..., carbon ones which seem to have a good reputation, and the guy at the lbs said the bike would certainly not be heavier than 8kg and quite possibly lighter than that.....

Where is the catch? I don't get it..

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CXR94Di2 [2510 posts] 3 months ago
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Huckfinn wrote:

...."why does the bike have to be carbon framed...?"

1) weight                                                                                                                                                                                     2) whenever I tried an aluminium vs carbon (for ex: Giant TCX) I much preferred the second...

@kevvjj : Looks like quite a cool bike, thanks! Altough, for that price, I would prefer the (even heavier) Giant Revolt with a 48/32-11/34.

@rdmp2 : budget mid-2k euros. Thanks for the Checkpoint suggestion! that's also a good one!

One thing though: why are they all so "heavy"? I mean, following the suggestion from CXR94Di2 I stopped at my lbs this morning. They'd charge 150-200euros to install a bike. Basically I could buy a Cube Agree C:62 frame + fork, Ultegra or Sram 22, these wheels:                                 https://www.chainreactioncycles.com/fr/fr/roues-a-disque-prime-pro/rp-pr... or even:   https://www.lightbicycle.com/700C-V-shape-36mm-depth-hand-built-carbon-r..., carbon ones which seem to have a good reputation, and the guy at the lbs said the bike would certainly not be heavier than 8kg and quite possibly lighter than that.....

Where is the catch? I don't get it..

 

Make sure the spec you want gearing IE . 21"-115"  wide tyre 40mm capacity and hydro disc brakes are possible on the frame you like.  

 

Once you've built one bike you quickly realise, its not difficult at all.  For a LBS making up bikes all the time, its a doddle for them and done with speed, so quite cheap.  If you want that gear range please ensure lbs confirms 

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Huckfinn [39 posts] 3 months ago
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Thanks for that.

I just don't get "Make sure the spec you want gearing IE . 21"-115"

Can you pls explain what you meant?

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