Stem lengths for a Giant TCR

devonbiker1

Hi there,

Picked up a new Giant TCR Advanced 1 in medium/large size. I am 5"10.5 with an inside leg of 33". I used to ride a ML Defy and found that comfortable, and assumed TCR sizing would be the same, however I feel a little stretched on the TCR with my hands around the hoods. In this position, my line of sight has the front axle and Ultegra logo on the front brake caliper visible just below the handlebar. I know the TCR geometry is designed to put you in a more aggressive position, but is this normal? I find my hands naturally want to sit on the bend part of the handlebar rather than the hoods. On the size chart I am on the border between a M and ML so theoretically I should fit on either bike, but perhaps I need a shorter stem?

I see on the Giant site there is a 2cm difference in top tube lengths and a 1cm difference in stem lengths (100mm on M and 110mm on ML). Should I try a 100mm stem? Would a 90mm stem make the steering too twitchy? Or should I leave it as it is and just get used to it? I currently have all the spacers below the stem.

Thanks

imposter2.0

As with other similar posts - it's difficult (ie impossible) to diagnose anyone's bike fit without seeing a picture of you on the bike.

timothyw

Stack and reach are the measurements that are most significant when comparing bike geometries. They correspond to the distance between the bottom bracket and the top of the head tube (essentially, where the stem attaches).

Assuming that you have the saddle set at the same position on both bikes (relative to the bottom bracket), then you can give the TCR the same fit as the defy by shortening the stem so as to equalise the two reach measurements (so if the TCR has 1cm more reach, then put a 1cm shorter stem on it....)

There's a good stem calculator here which will show you exactly what difference will be made by replacing the stem with a new one or adjusting it's position, flipping it etc - http://yojimg.net/bike/web_tools/stem.php

i wouldn't worry about it making the bike feel twitchy etc, such considerations are basically secondary in my experience to getting a decent fit (and if you look at riders riding a size small, they're already managing with stems smaller than any you are likely to use.)

figbat

I recently shortened the stems on both my road bikes as they also felt long to me, despite being the ‘right’ size. I went pretty extreme; 80mm on one and 70mm on the other. They were both immediately more comfortable/natural and whilst I can see why people might mention extra twitchiness, it isn’t in any way problematic or even, in most circumstances, noticeable.

I suspect the problem I was trying to solve was my own lack of flexibility and core strength, meaning a stretched out position put pressure on my lower back and neck. All good (or, at least, manageable) now.

devonbiker1

figbat wrote:

I recently shortened the stems on both my road bikes as they also felt long to me, despite being the ‘right’ size. I went pretty extreme; 80mm on one and 70mm on the other. They were both immediately more comfortable/natural and whilst I can see why people might mention extra twitchiness, it isn’t in any way problematic or even, in most circumstances, noticeable.

I suspect the problem I was trying to solve was my own lack of flexibility and core strength, meaning a stretched out position put pressure on my lower back and neck. All good (or, at least, manageable) now.

What size are your two bikes and what stems were on them originally?

bristolpete

100mm might make the difference possibly 90mm.

I am clearing out my ML giant bikes as whilst I used the geo table to factor in buying Giant bikes, the stack but mainly the reach can be a tad deceptive as whilst the reach akin to my old bikes (s-works tarmac), the seat tube angle is 73% so mildly slack in race bike terms. Basically, in my case, a ML is too big despite me thinking it worked. I spent two hours in a Giant concept store and will be, in due course downsizing to a Medium giant based on power fit advice, once I have sold my TCR SL.

But at your height, which is never a given the M/L should work.

Finally, do note you can flip the seat post clamp to gain more fore/aft on the rails and thus obtain more reach but at the behest of looks and of course potentially put more load on the quads each ride if not a good position.

figbat

I have a 56cm Cannondale Synapse and a M/L (53cm) Fuji Altamira 2.7. From memory the 'dale had a 120mm stem, the Fuji had the same. I always knew I was on the bottom end of the 'dale's fitment (but it was bought used). I am smack in the middle of the Fuji's. I'll admit the shorter stems don't look the part, but they feel great.

In fact, when I did the stem on the 'dale I did it in the cold snap - I then didn't ride it for a while. When I finally got out again I started riding and immediately felt really good on the bike, despite the lay-off. I had forgotten about the stem, but then remembered it and concluded that this was the source of my good feeling. When I did the Fuji it was the same - I felt like you before, most comfortable on the bends of the bars but now can ride the hoods easily.

No doubt I ride more upright than is de riguer but with the shorter stems I can still get down on the drops OK with no issues regarding how close the bars are to my knees and so on. If I was being fussy I might think about taking some length out of the brake cables to tidy up the cockpit.

All of the above is pure suck-it-and-see experience based on possibly sub-optimal frame sizing. So far it is working for me though. My next move is to put some shorter cranks on (I have a set of 170 to go on the 'dale to replace the 175; if this makes any apparent difference I'll do the same for the Fuji).

darkhairedlord

Bend your elbows!
Magically, you will take the stress out of your arms and find yourself closer to the bars you can't quite reach.

mrpbennett

I have an old Giant TCR Composite 2, recently replaced my stem with a Zipp Service Course SL Stem (as it was only few grams heavier than the carbon version, but £100 cheaper) I replaced it with the standard size i got on my bike which was 100m.

This was because i also bought Zipp SL-70 Aero bars which have a much shorter reach than the standard giant bars. As i did feel a little stretched out sometimes. So as many people here say, it all depends on the fit of your bike. If you're comfortable with the way the bike feels replace the stem with a better one for the same size.