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Dan
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31 Posts
Discussion Starter · #1 ·
Hi

I currently ride a Giant Defy 2013 Advanced size XL. I am right on line of L and XL and looking for a new bike. Age 51 not supple like riding 20 – 60 miles
I am looking at either Cannondale Synapse or BMC GF02. Shops are generally steering me to size L and are happy to offer me test rides.
The concern I have which I hope you can help with is that I worry a bit that the smaller bike will mean a more “bent” position as the seat will still effectively be at same height no matter frame size. I don’t want to ride in a position that ends up giving sore shoulders.

Oddly the shops have said the opposite will happen as the bar will be closer so less stretch so one counteracts the other.

The XL is a tiny bit stretched but – I know I could have rectified if I got shorter stem. I could get a longer stem and flip it as well on the Large I guess but would really appreciate your thoughts.
Am, I being too over- sensitive? It is quite a lot spend then find out I got it wrong.

 

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Banned Sock Puppet
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14,709 Posts
Did you test ride both sizes? Which one do you like the feel of better? My only concern is if the bike shop didn't have the larger size, are they just steering you to what they have?

Interesting that you mentioned L and XL. The Cannondale Synapse sizes their bikes numerically 48, 51, 54, 56, 58, 61. The Synapse is a great bike. OK, I'm slightly biased since I have one. :)

A few other questions to shed light on sizing. What is your inseam? What is the standover clearance (distance between top tube and your crotch where you stand)? You don't want this distance to be any less than 2 inches (5cm) or a dismount could be very uncomfortable. :eek:

It sounds like you very well may be on the cusp of sizes. If this is indeed the case and the only issue, a shorter or more upright stem could very well put you in the right ballpark.
 

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Dan
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31 Posts
Discussion Starter · #4 ·
Did you test ride both sizes? Which one do you like the feel of better? My only concern is if the bike shop didn't have the larger size, are they just steering you to what they have?

Interesting that you mentioned L and XL. The Cannondale Synapse sizes their bikes numerically 48, 51, 54, 56, 58, 61. The Synapse is a great bike. OK, I'm slightly biased since I have one. :)

A few other questions to shed light on sizing. What is your inseam? What is the standover clearance (distance between top tube and your crotch where you stand)? You don't want this distance to be any less than 2 inches (5cm) or a dismount could be very uncomfortable. :eek:

It sounds like you very well may be on the cusp of sizes. If this is indeed the case and the only issue, a shorter or more upright stem could very well put you in the right ballpark.
It is the 58 or 61. I have been to 3 shops the advice is inconsistent. Hence asking the people in the know
 

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I use reach and top tube length as my metric for the right size bike. A sloping frame bike, effective top tube length is the critical number. A quick search shows the Synapse has a 60.1 cm TT in the XL and 58.1 in the L. The Defy has a 59.5 in the XL so I don't think you are being steered wrong as far as fit if the Giant has worked for you. I generally like the feel of a smaller size frame in my fit range. If you feel too cramped on the L you can always fine tune with a longer stem.
 

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I hate to say it, but try both ways.

I ride a 60 but use a 100mm stem instead of 120. Even so, I have a good amount of saddle to bar drop (long legs). I tried flipping the stem to take away some of the drop, and it felt terrible. I flipped it back and even lowered one spacer and the comfort increased. Definitely goes against what one would typically think.

Point being, depending on your build, the extra drop but shorter reach might be more comfortable than less drop and longer reach.
 

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You don't have enough information about your fit to know whether a new size will be effective e.g. how much shorter of a reach do you require. The issue that you have is what amount of reach and height (stack) do the handlebars need to be. When these measurements are known, the measurements can be used to determine the stem length and angle and the amount of spacers on another bike of whatever size. You can then compare your fit on another bike with what you already have. It is possible to have the same fit on 2 different sizes of bikes.

Based on 2016 geometry, the 2 size Large bikes are less than 10 mm shorter in reach than your current bike, if your current bike has the same geometry as this year's edition. I don't have the data in front of me but it is something like 5mm for one and 6 mm for another. The 2 size Large bikes are definitely lower in height than the current edition of your bike. One is only lower by 10mm. Until you know the length and reach that your handlebars need be, there is not much to say about the size Large bikes.

I think you have 2 options before buying a new bike. One option involves going to a bike fitter and getting measurements and recommendations. Another option is to experiment with a shorter stem on your current bike and possibly try different amounts of spacers and angles until you find a more comfortable position. This takes time and effort. Also search the internet and become familiar with the concept of stack and reach measurement that is found in the geometry charts. Learn what the measurements mean and find the instructions on how to measure your bike. Learning these measurements allows you to apply the same technique to measuring the height and reach of your handlebars. Knowing these measurements allows you to calculate what your position will be on another bike. it would mean inputting data into a calculator for stem length, angles and amount of spacer. There are various calculators available on the internet.
 
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