Frame size, new bike fitting, questions

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bikerjulio
Posts: 1900
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

I'd stick with a 10cm stem. The reach is only going to be 0.5cm more (just look at that on a ruler!), but the bars are going to be slightly higher too, partially at least offsetting the longer reach.

I have a bike collection, and I have to tell you that can work comfortably within a 1-1.5cm variation in reach between bikes and not notice it.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

by Weenie


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GT56
Posts: 570
Joined: Fri Jun 05, 2009 9:40 am
Location: Switzerland

by GT56

DaleRider wrote:I'm in need of a quick sanity check here before I have my LBS order up a new SLR01 frameset.

I'm 172.5 CM tall which puts me at the large end of the 50cm frame and the small end of the 53cm frame. Currently my favorite frame and best fitting frame is my old 54CM CAAD8 R1000 circa 2004 or 05. Based on my hack job measurements, the CAAD8 has a stack of 540mm and a reach of about 585mm. I'm running a 100mm, -6* stem that sits on the 1cm FSA headset cap with no extra spacers.

Based on my backwards math, I'm thinking that the 50cm SLR01 with a 110mm stem and a 10-15 mm of spacers on top of the headset cap should put my bars in almost the exact same spot as my CAAD8. If I go with the 53 SLR01, I think that I'd need a 90mm stem that would be slammed on top of the head tube to get the 110mm of saddle to bar drop that I run.

Sadly the local shop doesn't have a 50 or a 53 to test out to see what would work best.

Any thoughts???


not having checked the BMC geo table, i think a 54 cm stack is a bit large for a 172,5 cm person, what is you saddle height, what saddle to bar drop are you looking for

DaleRider
Posts: 52
Joined: Thu Apr 18, 2013 12:34 pm

by DaleRider

Saddle height is 715mm from BB center and I like a 110 mm drop to the bars.

GT56
Posts: 570
Joined: Fri Jun 05, 2009 9:40 am
Location: Switzerland

by GT56

DaleRider wrote:Saddle height is 715mm from BB center and I like a 110 mm drop to the bars.



to achieve this drop, you need the 50 bmc (the 53 has a stack of 55+cm)

did you achieve the 110 drop with the 54 cannondale, seems hardly possible ?

jmsp
Posts: 43
Joined: Wed Mar 11, 2009 5:45 pm

by jmsp

Don't know if it helps but I'm 1,79 cm (82,5 cm inseam) and I ride a size 53 BMC SLR01 (2011 model) with a 110mm stem. I feels perfect and very comfortable for me, even in long rides. Knowing that, and with your height I'd choose the size 50. The 53 probably will be too big for you.

DaleRider
Posts: 52
Joined: Thu Apr 18, 2013 12:34 pm

by DaleRider

GT56 wrote:
DaleRider wrote:Saddle height is 715mm from BB center and I like a 110 mm drop to the bars.



to achieve this drop, you need the 50 bmc (the 53 has a stack of 55+cm)

did you achieve the 110 drop with the 54 cannondale, seems hardly possible ?


Yes. My drop is actually 112 mm give or take a few from the top of the saddle to the top if the bars.

Dimitri
Posts: 91
Joined: Thu Mar 03, 2011 7:07 am

by Dimitri

we sell a lot of BMCs. youre on the short side for a 53. obviously a lot of variables but people your height and slightly taller are on the 50.

it is a little tricky i guess, the 53 is almost like an extra size. BMC have 3 size frames (50,53,55) where most brands just have 2 (54,56). but i think its a good idea as these bikes fit a pretty average height range of cyclist.

DaleRider
Posts: 52
Joined: Thu Apr 18, 2013 12:34 pm

by DaleRider

Ok, so now I'm more undecided than ever.

I think I'll go with the 50 as its easier to raise the seatpost, add spacers, and a longer stem than to make a frame that is a hair to big work.

rijndael
Posts: 402
Joined: Tue Sep 20, 2011 12:54 pm
Location: Haines, AK - Temporarily

by rijndael

DaleRider wrote:its easier to raise the seatpost, add spacers, and a longer stem than to make a frame that is a hair to big work.


Yes, I just went through that and had to trade in my CAAD9 frame.

xjustice09x
Posts: 7
Joined: Thu Nov 11, 2010 9:29 pm

by xjustice09x

Im about 170cm and I have a size 50 team machine. I dont have much seatpost exposed, and use a 100mm stem. I would think that the 50 is probably the right size for you.

I test rode the 50 and the 53. Standover height was pretty close between them. The 53 was a touch too big for me but it still felt pretty comfortable to me. My other bike is a BMC SL01 size medium which has an effective top tube of 55CM which matches the 53 team machine. Im happy I went with the 50. After getting a retul fit I feel it definately was the right choice.

AGW
Posts: 477
Joined: Sun May 27, 2012 2:11 pm

by AGW

I plugged the numbers in to ye olde bike comparator. If it's 100% accurate, you'd need a 95mm -6* stem on a 5cm spacer to have an identical position to your current one on the CAAD8. If you went with the 50cm SLR01, you'd need a 100mm stem on 25mm of spacers. Of course, one test ride is worth a thousand internet comparisons. Good luck!

SLR01 53 (red) compared to a CAAD8 using the geo chart you posted:
Image

Image

DaleRider
Posts: 52
Joined: Thu Apr 18, 2013 12:34 pm

by DaleRider

After looking at the chart the 53 looks like the better option. I can still get my 110 mm saddle to bar drop and the extra 5mm of reach would hardly be noticeable. I've called every BMC dealer within a two hour drive and none of them have a 50 or 53 in stock. Maybe I should take is as a sign and look for a different frameset.

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bikerjulio
Posts: 1900
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

You could always get a Supersix :D
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

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jekyll man
Posts: 1570
Joined: Wed Apr 25, 2007 10:23 am
Location: Pack filler

by jekyll man

Your caad8 might feel "right" purely because you've spent so much time on it. Doesn't make it correct though....

If you're evenly proportioned, at 172 I'd say the 54cm dale is too big to start with. I'm 175 and had 54 dales and felt they were a tad too long for me. They used to do a "frameset only" in 53 which would have been ideal.

I'd go for a 50 BMC if i were you...
Official cafe stop tester

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bikerjulio
Posts: 1900
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

My conversion says that you are 5' 8".

Cannondale has this handy chart.

http://www.evanscycles.com/product_document/file/e60/9e4/ed6/676/cannondale-road-bike-sizing-chart.pdf

Which puts OP squarely on a 54 Cannondale.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



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