C50-Help me understand back pain

[Dan Le foot]

Hi gang.
I just rode the new (to me) Colnago C50 (58.7tt) that I just got from a forumite.
I set the bike up exactly like my Time VXR (58tt) and the Legend (59tt). Saddle to bar drop (5.5cm) and reach to the hoods are exactly the same on for all three bikes. Seat angle on all three bikes appear to be the same.
But after only 30 minutes on the C50 my lower back started to hurt. Got through a three hour club ride. Still a little painful after being off the bike for about 2 hours.
The ride characteristics of the C50 were great. But I have no idea what is causing the back pain.
You have any idea what might be happening?
Thanks.
Dan

[Louis]

When I set up a new bike I try to match the BB-to-saddle vertical and horizontal dimensions then try to match the saddle (sit bone area) to bar dimensions. How close are you on those four values?

(Assuming same crank length and pedals.)

[Elefantino]

I had a similar problem a while back with a Bianchi that was dialed in to match my other bikes. Seventy miles into my first ride I had to bail because my back was killing me. It went on eBay the next day.

I, too, would love to know what the deal is/was.

[Ken Robb]

you're older than when you rode the VXR. :)

[tv_vt]

try tweaking the seat angle. I did a century today and my lower back was bothering me for the first half. Lowered the back of the seat a hair and that fixed it. I've noticed this before. Even if it looks same as other bikes you have, try playing around with it. Also, setback is the same, crank length, same saddle and height from BB?? Tilt of brake levers and handlebars? Same bars, yes?

Good luck with it. Would like to see a ride report if you can fix the current issue.

Thom

[Dan Le foot]

you're older than when you rode the VXR. :)
Well, Ken.
I rode the VXR 3 days ago. I am a bit older though. :crap:
Dan

[WadePatton]

setback. don't fool around there. measure and match. guessing at sta isn't close enough. (and is not the measure needed)

reach and drop can be the same, but if your hips aren't in the right place...it doesn't matter where you put your hands.

[CaptStash]

Clearly the C50 is defective. Please send me your address immediately and I will remove it before this vehicle of the devil can do more damage! :banana: :banana:

[Keith A]

Dan -- I realize that my comments won't help solve your problem...but I have a Time VXR and a Colnago C-50 and haven't had any physical issues when switching between the two bikes. They are both fantastic bikes...but they do feel different.

[tv_vt]

ok, this is drifting, but Keith and Dan, what's the story between the two frames' ride? Dan has his VXR for sale. Reviews call it super stiff. Maybe this is a new thread, but I'd enjoy hearing about the differences between these two frames. (My carbon frame of reference is a Look 481sl.)

Thanks,

Thom

[Dan Le foot]

setback. don't fool around there. measure and match. guessing at sta isn't close enough. (and is not the measure needed)

reach and drop can be the same, but if your hips aren't in the right place...it doesn't matter where you put your hands.
Thanks Wade.
But I'm not getting it. Maybe you could expand on this.
The SA on the bikes are the same. I simply pulled the post/seat off the Time and placed in the C50 and set the saddle height from the BB to match.
I normally don't have a problem with knee over peddle position since my butt is trained to move up or back depending where the seat is on the rail. My knee knows what position is correct.

[Dan Le foot]

Dan -- I realize that my comments won't help solve your problem...but I have a Time VXR and a Colnago C-50 and haven't had any physical issues when switching between the two bikes. They are both fantastic bikes...but they do feel different.
That's really good to know, Keith.
The Robobank C50 is just about the prettiest bike I have seen. Hate to see it go.
When I 1st mount the bike my position seems spot on. Real comfy.
I moved the hoods up a bit (towards me) and will try again today.
Dan

[Dan Le foot]

I rode the bike for the 1st time yesterday with the seat about ½ “ too high. What an idiot. :crap:
When I set the bike up on Friday I set the seat height and took a short ride down the street. I found the cables needed adjustment and put it back in the bike stand. Now, the seat binder on the bike is way over the top tube leaving less seat post than needed for clamping. So I taped the correct position of the post and exposed more seat post for clamping. When I was done I forgot to drop the post to the correct location.(I never had a bike where I had to extend post for clamping)
In the heat of the competitive group ride yesterday (1st real ride with it) I didn’t notice the position of the seat. Focused more on not getting dropped. :bike:
I noticed immediately on the ride this morning. Adjusted the seat position to the taped level and had no back issues on the ride.
Bike rode great.
I’m so happy. But a little embarrassed. Thanks for your help, gang.
Dan

[Ken Robb]

you are so good about admitting your error you could be a major league umpire. :)