Crux size up or down?

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LittleSprinter
Posts: 264
Joined: Tue Dec 02, 2008 4:21 am

by LittleSprinter

I didn't want to hijack another thread, but similar question.

I'm looking to buy a 2022 Crux to be the n-of-one bike with a few different wheel sets. Going to use it mostly for road and hardpack gravel/farm roads. I've been a roadie my whole life and have a pretty comfortable road fit that I've taken on gravel roads a lot without issue. My goal will be to have the Crux fit more like a road bike than not.

Here are a few dimensions on my road bike, given those.

Would this group recommend a 49 or 52? I'm also 5'6 with a 29in inseam

Current bike
Top tube - 535mm
Head tube - 115mm
Stack - 526mm
Reach - 388mm

Crux 49
Top tube - 512mm
Head tube - 100mm
Stack - 530mm
Reach - 375mm

Crux 52
Top tube - 539mm
Head tube - 115mm
Stack - 547mm
Reach - 382mm

by Weenie


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CasualRider
Posts: 46
Joined: Sat Sep 05, 2020 1:36 am

by CasualRider

I would certanly go for 52. I ride Tarmac size 54 and wend with Crux 54 as well. Same reach and higher stack.No spacers and -12 degree 120mm stem on Crux to match the stack on my road bike. Tarmac has 120mm -6 degree and one spacer. Very happy in the end. I'm 5'9 and 31.5 inseem.
Last edited by CasualRider on Mon Nov 28, 2022 2:13 am, edited 1 time in total.
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Karvalo
Posts: 2882
Joined: Fri Aug 10, 2018 6:40 pm

by Karvalo

Listing your current frame dimensions is a good start but you need to add how you're set up on it (stem length, angle, spacer stack at least) if you want to get anything better than a guess coming back.

Rudi
Posts: 263
Joined: Tue Apr 08, 2014 6:43 pm

by Rudi

Are you more concerned about your reach, or stack?

The 49 is only 4mm taller than your current set up. The 52 is 21mm taller.

Reach on the other hand is closer on the 52. 6mm vs. 13.

If your current set up has circa 20mm of spacers then the 52 looks to be a better choice. If you are slammed then the question would be "would you be happy 2cm higher at the front.

If stack is your limiter, would you be happy with a longer stem on the 49?

Edit - https://bikeinsights.com/ might help you visualise it better.
Cervelo R3 - 5.4kg viewtopic.php?f=10&t=142420

User avatar
stringbean
Posts: 120
Joined: Sun Jul 06, 2008 2:18 pm
Location: Ireland

by stringbean

Question that many are asking at the moment when looking at the crux.Sizing is a bit strange because of the long seat tube(we forget it's a cyclocross bike where bigger main triangle is needed to shoulder the bike)
I was in the exact same predicament except between a 52 and 54 crux( I ride a 54 SL7)
As mentioned in previous posts is all personal.I ended up going for a 54 with a straight seatpost and a slammed stem and so far very happy with positioning.
It's a choice you have to make.
Smaller frame with Kay back seatpost and spacers under stem with possible toe overlap.
Larger frame with straight seatpost slamming stem but little seatpost sticking out if frame that might look weird.

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stringbean
Posts: 120
Joined: Sun Jul 06, 2008 2:18 pm
Location: Ireland

by stringbean

stringbean wrote:
Mon Nov 28, 2022 1:24 pm
Question that many are asking at the moment when looking at the crux.Sizing is a bit strange because of the long seat tube(we forget it's a cyclocross bike where bigger main triangle is needed to shoulder the bike)
I was in the exact same predicament except between a 52 and 54 crux( I ride a 54 SL7)
As mentioned in previous posts is all personal.I ended up going for a 54 with a straight seatpost and a slammed stem and so far very happy with positioning.
It's a choice you have to make.
Smaller frame with lay back seatpost and spacers under stem with possible toe overlap.
Larger frame with straight seatpost slamming stem but little seatpost sticking out if frame that might look weird.

LittleSprinter
Posts: 264
Joined: Tue Dec 02, 2008 4:21 am

by LittleSprinter

Thanks for the reply!

Yeah I actually dug further and found that the stack/reach is of the 49cm is almost identical to my old 2005 Specialized SWorks E5, which was the best handling bike I've ever had when I ran with a 10mm spacer and 110mm stem and a small bit of setback.

I'm actually leaning this way as the reach would be easier to accomplish with a longer stem and would rather have flexibility on moving the seatpost more on the smaller frame. I've got quite a bit shorter legs relative to torso.

Thoughts on that logic?

lightklein2
Posts: 25
Joined: Sun Nov 09, 2003 9:00 am

by lightklein2

Hey LittleSprinter

which size did you select?

LittleSprinter
Posts: 264
Joined: Tue Dec 02, 2008 4:21 am

by LittleSprinter

Ended up with the 52cm with a 100mm stem and moderate setback on the seatpost!

Still tweaking the right stem/saddle position and may go with a zero setback in the end. More pictures to come after the snow melts a bit here and can actually take it out.

by Weenie


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