Crux sizing advice

[gjc985]

Right now I ride a 55 wilier izoard on the road and a 55 - Felt f75x for cx and looking into getting a crux frame, but unsure if I should go with the 54 or 56.

Inseam: 32.75
Trunk: 26.5
Forearm: 15.5
Arm: 28
Thigh: 24
Lower Leg: 22.5
Sternal Notch: 60
Total Body Height: 71


These are my measurements. Any advice/recommendations you could provide would be great. Thanks!

[benb]

I rode my friends 56 Crux for a bit this weekend.. I'm 73" tall with a 34.6in inseam. He's also 6'1".

The 56 was just about perfect for me.. I would have slid the seat back a little and that's about it. I don't think he changed the stock stem or anything.

So I'd maybe guess 54. Hard to say though as I don't know all my measurements off the top of my head.. if your torso is longer than mine you might be good on the 56 too if you wanted a more upright position.

There was a recent thread about creaking BBs... he has the Praxis Works cranks on his Crux and it was creaking like crazy and he got it in September. (Although he has probably rode it > 1000 miles in that period.)

The cranks make me scared as I want to buy a Roubaix soon and I'd assume the BB is some similar setup, although I am almost certainly going to go with one of the models that comes with the Shimano crankset.

[rnhood]

I rode my friends 56 Crux for a bit this weekend.. I'm 73" tall with a 34.6in inseam. He's also 6'1".

The 56 was just about perfect for me.. I would have slid the seat back a little and that's about it. I don't think he changed the stock stem or anything.

So I'd maybe guess 54. Hard to say though as I don't know all my measurements off the top of my head.. if your torso is longer than mine you might be good on the 56 too if you wanted a more upright position.

There was a recent thread about creaking BBs... he has the Praxis Works cranks on his Crux and it was creaking like crazy and he got it in September. (Although he has probably rode it > 1000 miles in that period.)

The cranks make me scared as I want to buy a Roubaix soon and I'd assume the BB is some similar setup, although I am almost certainly going to go with one of the models that comes with the Shimano crankset.

I do not own a Crux, buy have ridden them. I am also 6'1", but with a 90.4cm inseam. The 58 fit me the best...I thought, although if I was planning to race then I might opt for a 56.

I have right at 40K miles on my Tarmac (pf30) and other than an overhaul needed to replace bearings at 30k miles, there has not been any squeaks or clicks with it. Its always run perfect. The one time that I thought it was squeaking, it turned out to be my cleats. I had the new blue Shimano cleats with 7900 pedals. I changed the pedals based on a thread on this forum (I think it was 11.4 that indicated a cleat difference). That immediately solved it.

Having said this, modern Tarmacs/Roubaixs and the such use BB30 - which arguably require a little more precision (so I've read). I have read reports of creaking on these but, there are a bunch of modern Specialized bikes with BB30 in our local club and they never have issues. It might be more the issue of who installed it...a shop or one's self. Nevetheless, I can understand the desire for a Shimano crank. I would be perfectly content with one on my bike also.

[John H.]

Body dimensions mean squat.
What is your saddle height, saddle setback, reach from tip of saddle to center of bars, and drop from bars to saddle on your favorite bike?

[KonaSS]

Body dimensions mean squat. This

But I would compare your Felt to the Crux geometry. I think the 56 will be the closest.

[biker72]

Go to your LBS and try them both out. Make a decision then.
I'm 6'2" and ride a 58cm Crux.

[gjc985]

Here are the results from a fitting I did for my 55 road bike...I'm thinking of buying a frame used and I can get a great deal on a used 54 or an ok deal on a used 56


Saddle height (cm) 75
Saddle fore/aft (cm) 6
Reach (cm) 55.5
Drop (cm) 7
Stem Length (cm) 110
Stem rise (deg) 7
Crank length (cm) 172.5
Saddle width (cm) 145

[John H.]

56 will likely be better at your saddle height and bar drop.
54 will require either a positive rise stem and/or a fairly large spacer stack.
I ride a 54cm with a saddle height of about 73cm- fits me well, but it would be pretty small if my saddle height was 75cm.

Here are the results from a fitting I did for my 55 road bike...I'm thinking of buying a frame used and I can get a great deal on a used 54 or an ok deal on a used 56


Saddle height (cm) 75
Saddle fore/aft (cm) 6
Reach (cm) 55.5
Drop (cm) 7
Stem Length (cm) 110
Stem rise (deg) 7
Crank length (cm) 172.5
Saddle width (cm) 145

[benb]

I still think the 56 is right but your fit is wildly different than mine or my friend's... we both have saddle heights ~79cm and setback ~9cm so the 56 is the downsize option for more drop and keeping the reach manageable.

If I had a setback of 6cm I could probably ride any 58 with a 120mm stem slammed... life would be way easier.

[gjc985]

Ended up buy the 56. Thanks for all the advice!