If you are in between frame size, go up or down?

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KCookie
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by KCookie

As this is WW you have to go smaller, smaller is lighter. That's what this forum is all about. 😀

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stockae92
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by stockae92

Thanks for all the advise. The head tube length is a concern for me.

My current setup on a 58cm frame is pretty much as low as I would go. I do worry if I go with a smaller size, if the head tube length is shorter, I would have to put spacers under the stem. Or maybe a endurance geometry with taller head tube (in a smaller size frame) would solve the problem.

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srshaw
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by srshaw

My first real bike was too big, even though for my height it should have been ok. I have long legs and short torso. Most advice seems to be to go bigger, but I have found they then become too long. I'm 5'10 and now usually go 54cm.

Since most manufacturers use stack and reach measurements, Its fairly easy to compare differrent frames.

spdntrxi
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by spdntrxi

I've done it both ways... current main bike I purchased for the long haul ( I think anyways) and went up.. if I was to get a predominately "race bike" I might go down a size.
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donald
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by donald

In general I would go smaller. Do you know what frame you are interested in? Different manufactures have different lengths in top tube and head tubes in the same size frame. It is good to know what the exact dimentions are of any frame you are interested in.

Zakalwe
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by Zakalwe

I think the correct practice is to go two, perhaps 3, sizes smaller

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pdlpsher1
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by pdlpsher1

To make the process easier just find the frame size such that you’ll end up with 180mm exposed seatpost and a 130mm stem. This will give you the perfect bike fit.


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Bigger Gear
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by Bigger Gear

Zakalwe wrote:
Thu Apr 19, 2018 7:32 am
I think the correct practice is to go two, perhaps 3, sizes smaller
Exactly correct for the World Tour riders. Two examples I can think of especially stand out: Ryder Hesjedal who is 6'3" or 1.90m riding a 56 cm Cannondale (or Cervelo). His Cervelo looked exceptionally stupid, because of the long head tube. He really needed a custom setup. And also Philippe Gilbert on BMC, he is 5'10" or 1.79m riding a 50cm frame! I have noticed since going to QuickStep and riding on a Specialized that Gilbert's fit has evolved, he's riding a bigger bike and he is a bit more upright.

Just remember that a WT rider's fit means nothing for the average person. They ride over 30000 km each year, and have a dedicated team of sports physios and massage therapists keeping them limber. All of that contibutes to them being able to ride a position the average person (even at an elite amateur level) can not ride.

Zakalwe
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by Zakalwe

I wasn’t being entirely serious, btw

bremerradkurier
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by bremerradkurier

Bigger Gear wrote:
Thu Apr 19, 2018 5:09 pm
Zakalwe wrote:
Thu Apr 19, 2018 7:32 am
I think the correct practice is to go two, perhaps 3, sizes smaller
Exactly correct for the World Tour riders. Two examples I can think of especially stand out: Ryder Hesjedal who is 6'3" or 1.90m riding a 56 cm Cannondale (or Cervelo). His Cervelo looked exceptionally stupid, because of the long head tube. He really needed a custom setup. And also Philippe Gilbert on BMC, he is 5'10" or 1.79m riding a 50cm frame! I have noticed since going to QuickStep and riding on a Specialized that Gilbert's fit has evolved, he's riding a bigger bike and he is a bit more upright.

Just remember that a WT rider's fit means nothing for the average person. They ride over 30000 km each year, and have a dedicated team of sports physios and massage therapists keeping them limber. All of that contibutes to them being able to ride a position the average person (even at an elite amateur level) can not ride.
It's kind of interesting to look at mid to late '80s pro positions vs. current ones, especially given the longer format of the TdF pre 1988.

IMO, there start to be some handling drawbacks going the small frame/long stem route, maybe due to how weight loading is distributed on the front vs. the rear wheel.

Bigger Gear
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by Bigger Gear

Zakalwe wrote:
Thu Apr 19, 2018 5:14 pm
I wasn’t being entirely serious, btw
Yes I knew that but should have indicated it in my response. But it is definitely interesting to see the evolution of bike fit over the years, at the highest level. Guys ride more forward and with much greater saddle-bar drop than 20/30/40 years ago. I suspect having wind tunnel data and image capture fit tools has allowed sport science to figure certain things out on a much higher level.

Zakalwe
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by Zakalwe

A lot of that has to do with bar shapes and integrated shifters though, old bikes with little saddle/bar drop had massive drops and there weren’t hoods to rest your hands on. You didn’t need such a low bar height as you do now, where hoods are the primary position for a lot of riders and shallow drop bars are better suited to most needs

morganb
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by morganb

Zakalwe wrote:
Fri Apr 20, 2018 1:59 pm
A lot of that has to do with bar shapes and integrated shifters though, old bikes with little saddle/bar drop had massive drops and there weren’t hoods to rest your hands on. You didn’t need such a low bar height as you do now, where hoods are the primary position for a lot of riders and shallow drop bars are better suited to most needs
Something interesting from an interview with Viviani, his ViAS has lower bar set up than his Tarmac and he essentially said he can't use the drops on the ViAS for regular riding and only gets in them for the sprint.

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themidge
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by themidge

Yeah I saw that interview too (I think it was on GCN) and thought it was pretty interesting. If he doesn't feel the need for the drops on his Vias, then I'm not sure why he wants them on the Tarmac, obviously he likes riding on the hoods. Perhaps if there are long descents (ie. hills, not terrain for a Vias) then he wants the extra control of the drops :noidea:.

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Zakalwe
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by Zakalwe

Maybe he just doesn’t expect to sprint in such a low position in a race where he’s chosen to ride the tarmac

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