how short is too short for a stem ?

Russman

Can I ask, is an 80mm stem too short on a road bike from a handling perspective ? basically if I need an 80mm stem to a better fit, is that still ok to do without compromising the stability of the bike ?

Thanks

paddymacsporran

What type of bike?

Russman

Its a Felt Z100 road bike, came with a 110mm stem that I've replaced with a 90mm and I'm considering going to an 80mm one.

I may just go for a proper fitting session to get it right......

Lumen

80mm is probably into "dodgy fit" territory unless you're a midget.

You could always move the saddle forwards instead. That's not how you're supposed to fit a bike, but it might be the lesser of two evils.

I've used a 50mm stem on a TT bike and didn't crash, though I wasn't trying very hard.

Russman

Ya, thats what I was thinking alright - "dodgy fit" territory - a good turn of phrase !

petethedrummer

I had a 65mm stem on a road bike for a while. I didn't notice any handling problems.

papac

petethedrummer wrote: »

I had a 65mm stem on a road bike for a while. I didn't notice any handling problems.

I agree. I have had very short stems and had no bother.
Doesn't actually change the handling of the bike -just alters the feel of the steering and you get used to that quick enough.

Lumen

papac wrote: »

Doesn't actually change the handling of the bike -just alters the feel of the steering and you get used to that quick enough.

A short stem and a rearward seat position will definitely give different handling to a longer stem and more forward seat position, because the centre of mass of the rider is differently situated.

I'd guess it would make the biggest difference descending.

papac

Lumen wrote: »

A short stem and a rearward seat position will definitely give different handling to a longer stem and more forward seat position, because the centre of mass of the rider is differently situated.

I'd guess it would make the biggest difference descending.

of course any change in the centre of mass of the system will affect the handling somewhat- I probably meant does not change the geometry.

i still would argue that the altered steering "quickness" will be the most noticable difference and that a rider becomes used to that quickly enough.
if Russman finds his 90mm ok then I can't see an 80 being a huge issue wrt centre of mass shift.

Edit. If you consider how much you shift CoG when you go from the hoods position to the drops a 10mm stem change is pretty miniscule surely.

paddymacsporran

Russman, I've got a 80mm stem I got with my Canyon that is no use to me, happy to give you it so you can try out that size.

Well, it is christmas.....

What size is the bike in relation to you? A stem short as that would make me think the frame might be loo large?

billy.fish

I'd say -10mm would be to short

Honestly if it feels good, do it

ROK ON

I have spent a lot of time experimenting with stems and have about 11 for three bikes.

As a suggestion, instead of going shorter can you go up - that is get a stem that has a raised angle. This has worked for me in the past.

Also I know nothing about you, but in my own case as I have gotten fitter I have started going back to longer stems.

If I was to buy another bike I would get a small frame with a longer stem. I find that that set up handles corners and descent better. YMMV.

Russman

paddymacsporran wrote: »

Russman, I've got a 80mm stem I got with my Canyon that is no use to me, happy to give you it so you can try out that size.

Well, it is christmas.....

What size is the bike in relation to you? A stem short as that would make me think the frame might be loo large?

Thanks for the offer paddy, much appreciated, I have an 80mm stem though (the curse of CRC !!:)).
I do suspect the frame might be too large, its a 58cm frame and I'm only 5' 10". On Felt's website for sizing it indicates that at my height a 56 or 58 is the correct size for their Z Series, so maybe I just need to get a little more flexible.

paddymacsporran

No worries - I'm 5'10" and my winter bike is a 52cm compact Canyon with 120mm stem, my good bike is a 53cm Look 586 with 110mm stem, I'm a 32 inside leg. Both have a sloping top tube, so a traditional/standard geometry frame size for me would be 54/55cm tops.

58cm would be too big for me, biggest I rode was a 56cm De Rosa, and I needed a 90mm stem on that.

Vaaltron

On the subject of stems. Choose a length that gives You comfort in the riding position without having to over reach. On a road bike for example choose a stem length, that while You are in the seated position with Your hands on the top of the brake hood's, Your elbow's should be slightly bent.

cantalach

The ability to get away with a shorter stem probably depends on the frame. My Giant TCR has an 80mm stem angled up and my Cervélo RS has a 100mm stem angled down (albeit with a much taller head tube) and I've never found the handling to be all that different between the two...I'm probably slightly more confident on the Cervélo alright but not dramatically so.

paddymacsporran

Good advice, bu that kinda depends on an individual's interpretation of 'slightly' though, doesn't it?

Easy way to check it's right is when you're riding with your hands on the hoods, when you look down at the front wheel the hub shouldn't be visible as it's obscured by/in line with the bars.

doozerie

As already discussed, "correct" stem length will depend on a bunch of things, not just your size and level of flexibility but also the geometry of the frame. The suitable size for each individual will fall within a range and that range will differ from person to person and also from frame to frame for the same person. I'd typically go for a 110mm stem myself but out of 3 road bikes my two best fitting bikes have a 120mm stem in one case and an 80mm stem in the other (and the fit on both bikes is actually very similar). The one with the 80mm stem is a Canyon and it handles better than my other two road bikes.

So, depending on the frameset, based on my experiences I would say that an 80mm stem might be fine. I wouldn't have said that prior to having bought my Canyon though so either I am more open-minded now or just more confused than ever!

Russman

paddymacsporran wrote: »

Easy way to check it's right is when you're riding with your hands on the hoods, when you look down at the front wheel the hub shouldn't be visible as it's obscured by/in line with the bars.

I've seen that rule of thumb before alright, is that regarded as a good starting point ?

chakattack

paddymacsporran wrote: »

Russman, I've got a 80mm stem I got with my Canyon that is no use to me, happy to give you it so you can try out that size.

Well, it is christmas.....

What size is the bike in relation to you? A stem short as that would make me think the frame might be loo large?

Hi Paddy,

How much do you want for the 80mm stem? For modern oversized bars I assume?

paddymacsporran

Thats regarded as a goos starting point Russman - I'll pm you Chakattack