Quote from: Risckys on November 11, 2020, 09:16:08 AM
I think if you could go with a size M, but with a lot of seatpost outside!
I am on a 75.5cm seat height in size M, the measurements of the frame are long!

Hi Risckys,
Could you post a pic of your bike, please?

Quote from: dhengen on November 09, 2020, 12:13:19 PM
Hey - I'm late to the discussion, but I was between L/XL sizing and sized down for lots of the same reasons you are considering it. From all your replies you've given, I think you want to size to M and I think you should trust your intuition, which is based on some solid data and your gut feeling. Your point about size M on this bike being a L on most mainstream brands is exactly why I sized down as well. Have fun, after all this is riding bikes!

Thanks, definitely I'm going to get the M, it makes more sense to me. I just wanted to have some feedback, by no means to start a discussion.

Quote from: QuentinLL on November 06, 2020, 07:47:34 AM
Stem
Yes i did try different stems on my 65° HTA bike. When stem is longer than 60mm this is a very strange sensation et poor handling.

STA
I have a custom geo hardtail 76° STA / 65 HTA / 476 reach and a 73,5° STA / 69 HTA / 428 reach hardtail Orbea Alma. The Orbea Alma offers better traction on flat tracks but less traction on steep climbs, because the weight is too much backward. The best traction is offered when the saddle is verticaly aligned with the rear axle or a bit forward. On my Orbea Alma i feel like my weight is backward the axle (i am not sure if i am clear ). PS : the vertical and horizontal length between saddle and bars is exactly the same between all my bikes. The difference doesn't come from the positionning.

XCO/XCM or downcountry ?
I understand your need. You are trying to get the "best of both worlds". Downsizing and "modifying" a downcountry geo to fit XCO/XCM geometry (old or not) is probably a bad idea in my opinion (suspension feel with your ass at 73° instead of 77°, handling with longer stem...).

The reviews don't recommend the NS Synonym for its pedaling quality. If you are into XCO/XCM you will certainly find it lacks pure pedaling performance (vs Scott Spark and Orbea Oiz for example) and moreover you will not have the benefits of the downcountry geo because downsized + long stem. Instead of "the best of both worlds", maybe it will results in "the worst of both worlds".

My need is a mini enduro bike with the weight of a XC.
Your need is a pure XC that descends better.
Maybe you are right and you need a M with longer stem and saddle backward... let's give it a try if you are not afraid of being disappointed. I hope you'll enjoy it 

I just found out that the Synonym Race runs a 70mm stem on the M and 80mm on the L , so is not that I have to modify anything.
The only thing I should do is to have more seatpost exposed but in my opinion, the size of a bike doesn't come from the seat tube lenght, clearly in this case is a matter of short ST due to a lot of slopping, ALL the rest of the measurements are spot on with a bigger size in any other brand.
You are also right, you have better traction when you put most of your weight vertically over the rear axle, but it is impossible that you are backwards of your rear axle on your Alma, the slope of the climb should be too steep or you would have to wheelie all the time.
Also the pedaling efficency of a bike would be determined from your position on the bike and the chainstays lenght, damper/suspension system/set up.
The chainstay lenght is just 3 mm longer than my Scalpel (I assume it would feel a little less reactive). If your position on the saddle is the same, then your damper set up works to stop any bobbing when pedaling, it can be a pretty good climber.

Quote from: theirishrider on November 06, 2020, 06:17:53 AM
Roby13 has some really good points. He wants to maintain the saddle to BB position due to knees: 'Already tested with different saddle positions and if I go to much over the BB, on long races my knees start hurting.'
I personally like my position where my knee is infront of the pedal axle (gives me less pain on the patellar)
I've not had issues with rear traction or front wheel lift on super steep tricky rocky assents but also I've not ridden a Scalpel so I don't have a point of reference. I can tell you that the slightly lower steep turn performance is offset by a greater degree by the descending ability.
I'm riding national XC points series on this bike next summer so I guess that will be the proof. If it's any guidance, Michał Topór was riding it seems like M at the world cup youtube.com/watch?v=_ri22H12QTg which seems suited for his height. You might get best of both worlds with the M with a slightly longer stem, but I don't know. What length would you have to run to get the reach you want?

If it's any help, would you like some images of me mounted on the bike? with 2 stem positions? - ive no idea if that would help

I would have to run a 70mm stem on the M which I find right for a xc modern bike. (same as NS is mounting on the M an L sizes).
The only thing I would need is to have more seatpost outside the frame and this would also compensate the actual seat tube angle.

I don't want to upset anybody here or deviate the threat so I'm going to try for the last time to explain my point.
Let's say I'm going to buy a new xc bike with modern geometry. In terms of HT angle, ST angle and wheelbase the closest a I could find are the BMC, Unno and Mondraker. On any of this brands I will take hands down the L size which is the one I have always ridden and I don't think any of you would advice me to by the XL. Well, if I take the L from Carbonda it would equal a XL from those brands.
Of course I can ride a XL just lowering the saddle on those and due to the long wheelbase it would be stable and planted on the downhills but it won't feel nimble or fast cornering or going up, which you really need on xc bike.

Quote from: Denis on November 06, 2020, 05:00:14 AM
Mein Gott! Looks terrible. Trying to make oldschool xc\road bike from frame with modern geometry is bad idea. If you want oldschool xc bike, that frame is just not your choise.

I agree the stem is way too long for that bike but this was not my point.

Here you have different modern geo charts, as  you can see, the carbonda has longer reach and wheelbase in M than the others in L.
The only bike I could find with a similiar wheelbase for the same size is the Transition Spur, but even this one has a 25mm shorter reach.
If you can find any other bike on the market with same/similar HT angle and ST angle with the same reach and wheelbase (for the same size) of the carbonda you can post here the geo chart and we can talk about it.

Quote from: QuentinLL on November 06, 2020, 02:45:47 AM
Hahaha !  A "downcountry" bike downsized with a 120mm stem ? I think it is the worst idea for both handling and power.
As acedeuce802 said : The slack HTA, steep STA, long reach, and long wheelbase all play together.

If you play around with that, it will be shitty for sure. Long stem with slack HTA is a terrible idea for downhill handling.
As well as saddle set up backward is a bad idea for uphill.

Back 10 years ago, every body were riding 650mm handlebar. On modern geo 29" bikes, nobody would do that.
You are entering the future of xc geo, do not be afraid, forgot your old bike geometry and take a L you won't regret it 

PS : spanish people are not tall. A L in Spain is a M in France and S in Denmark   

Is not my idea to mount a 120mm stem, according to my measurements 70mm would do.
Did you ever tried a longer stem on a bike with slack angle? because IMO there is a lot of bro science about geos, most important thing on a bike which needs to climb efficient (anybike at some point) is the saddle position, if you shift your saddle forward you are going to have less weight on the rear wheel and also less traction. I don't get the point to change my actual saddle position which I find perfect for power/comfort/traction efficiency. I also never had an issue of my front wheel wanting to rise on steep climb so I don't need to put more weight on the front when climbing.
Then it comes descending which you never do on the saddle and you want a longer reach from the BB to mount a shorter stem and a slacker HT angle and is what this bikes offers.
This frame is way longer than any other bike (even the new modern geometry bikes) and the only measurement which can relate it to a M frame is the seat tube lenght, which is also the less important as you can play with the saddle height/offset and that's because the bike has a really steep slopping.
By the way, is pretty stupid to say that because the people in Spain is shorter the size is different when all the rest of the brands keep the same sizing chart.
Do you race XC or XCM? the demands of those races are different to the recreational normal riding, I have to be able to put a high amount of power for a long sustained time to go up a climb. Already tested with different saddle positions and if I go to much over the BB, on long races my knees start hurting. It's the same comparison between a road and a TT bike, on a tt bike, because you lean over the handlebar, your position is way more in front of the BB, which usually drops the power you can put on the pedals but allow you to be more efficient in terms of aerodynamics which makes you go faster on the flats, but as soon as you start climbing and the speed is lower, you want to have the most efficient and powerful psotion (otherwise they would ride TT bikes all the time at the Tour de France).
I also understand, if for your kind of riding you want to sacrifice some climbing efficiency to get more of the bike going down, is fine for me but is a different way of riding the same bike.
If you check the Unno Horn's geo (created by Cesar Rojo, pioneer of all the new modern geo bikes) has a shorter reach, shorter wheelbase but the same 440mm seat tube lenght and 67 degrees HT.
Same with BMC fourstroke, Mondraker Podium, etc all of them modern geo bikes and this frame in M has a longer reach and wheelbase than the others in L.

Here is Patxi Cia's bike, a Spanish xc racer which is built with the same approach (xc/xcm aggressive riding). He is shorter (1'75 mtrs) and rides a S size.
B
A 9'8kg rocket

Quote from: Colt__Seavers on November 05, 2020, 11:28:43 PM
If you want to keep your current position like on the Scalpel, keep the Scalpel! This frame has a completely different approach and you seem not wanting to live with it. The FM936 is true to size. If you run L in your other bikes, also use an L with this frame!
You asked for advice and everyone told you to get the L, but it seems you don't want to listen. Your body size and saddle height screams for the L. But if you want the M so badly, take the M, but don't blame anybody but you if you don't like it.
If I read through your comments I'd suggest not to buy this frame at all. It's not what you're looking for.

I thing you got it wrong. I understand the approach of this bike and this is exactly what I'm looking for (slacker HT angle and longer wheelbase and lower BB), which I actually can achieve on a M frame keeping my actual position(50mm longer wheelbase and 67 HT angle) for sure I'd never blame anybody for my own choice.
The whole thing is to have a bike which I can pedal up on my races almost so effective as my Scalpel and go down faster/easier. Some marathon races I do we hit climbs over 1000mtrs in one go (mostly on even surface, fire roads or even Tarmac) and then descent those same 1000 mtrs on trails.
As I said before, on the M frame I would be able to mount a 30 mm shorter stem keeping my actual position and have a much more DH oriented bike as soon as the things go down.
In Spain, the Brand Mendiz is offering a model with the exact same frame, and they also sell the M frame from Carbonda as an L https://www.bicismendiz.com/bicicletas/mtb/mendiz-x40xc-configurador#.
In my opinion, everybody rides different and have to build the bike according their needs, I don't want the M so badly, I just want to build the bike which offers me the best performance for the riding I do. If I wanted a bike to focus on descending I wouldn't mind to have the L but for me is also important that the bike is reacting fast uphill on tight corners and feels effective on long stady climbs.

Quote from: QuentinLL on November 05, 2020, 01:15:07 PM
When i center the pictures on the rear bike axle, you can see that the geometry, wheelbase, angles, BB height etc. are very very different.
But saddle->handlebar length is the same => same "pedaling" position



The FM936 is a modern geometry, it should be riding hard, with short stem. Take a size L and downsize your stem 

Hi Quentin, thanks for all those graphics and don't want to deviate the thread, but even when the saddle/handlebar distance is the same, the pedaling position it is not. In this example you are much more over the BB which I don't want to change from my actual bike as I train on three different bikes and have it dialed in terms of power and comfort, this is why I think it would be easier for me to get that position on a M frame. I would like to keep the same saddle to BB height/offset and distance to the handlebar. Maybe it would not be possible on a L as the reach is much longer.

Quote from: QuentinLL on November 05, 2020, 03:12:21 AM
Hi,

The reach is longer but the seat tube is steeper.
What you need to look at is the distance between saddle and handlebar (horizontaly and verticaly) to have a nice riding position.
I am 1,78m with 75cm BB to top of the saddle. With a L size and a 40mm stem (what i like to ride), I have the same horizontaly and verticaly position as my Orbea Alma size L with 60mm stem.

The main difference is that on steep uphill, with the Orbea Alma, I was seated "on the rear wheel". What means poor handling and struggling to keep the front wheel on the ground.
Conclusion : I suggest you take the Carbonda L size.

Hi Quentin and thanks for your answer.

I want to keep my actual position on the new frame which I find perfect,  it would not be a problem even if the seat tube is 4 cm shorter, I just need to set my saddle 10 mm backwards.
The thing is, that this frame in M has a 30 mm longer reach than my Scalpel in L which is perfect if I want to build it with a shorter Stem
but in L it is 55mm longer .
Also the wheelbase in M is 50 mm longer than the Scalpel in L, the L would be a huge 100 mm difference.
The kind of riding I mostly do is agressive XC an marathon races so a reactive bike would be more of my taste.

Hi guys,

I found thist threat yeasterday and I I read the whole thing because I want to order this same frame, thanks for all that cool information .
My only thought is ,wich frame size would fit me better.? Comparing the geometry with my actual Scalpel Si in L, the carbonda frame is pretty big so I'm considering downsizing to M. What you guys think?
I am 1,83m tall and I usually have my saddle height at 77,5 cm (BB to top of the Saddle).
Anyone riding a M with more or less the same saddle height?

Thanks again and keep posting those cool bike pics!