Choosing the correct stem

[rockyraccoon]

I've been riding my Specialized Allez 16 year 2010 for a few months now. Lately I've started to notice that I usually ride with my hands on the hoods but sometimes on top of the handle bar which gives me a more upright and VERY comfortable position.

The stem on the bike is the stock Specialized (110mm, oversized and angle 12) and was flipped by myself after recommendations from some CC members. It has improved a lot and I feel much more comfortable. However I still would like to "bring" the hoods even closer to me.

How do I figure out what stem I need and its correct angle (degree) to bring the bars back? Would I achieve that with a shorter stem?

I have looked everywhere for a 100mm stem and angle of 12 degree but cannot find it. Would a 100mm/10 degree compromise to much? Would this be the ideal stem?

Thanks in advance!

 

[irw]

Would something like this be of any use to you?

I have just bought a new hybrid bike which came with a very shallow stem, which set the handlebars much further forward than I was used to- as I found out to my great discomfort 10 miles into my first ride! I bought one of those adjustable stems, set it to approximately match my old MTB, and it improved the ride considerably!

Ian

 

[slowmotion]

RR, spookily enough, I've been going through the same process. I have just bought a Specialised Secteur 2010 with a 58cm frame size. I had very brief test rides on 56cm and 58cm frames. The bike shop spent a lot of time making adjustments (many thanks Tim, London Victoria Cycle Surgery). Being completely new to riding a road bike, I really didn't know what a comfortable fit should feel like. The 56cm felt great as regards reach to the hoods, but my knees felt like they were in my armpits. The 58cm frame was great to pedal, but I felt maybe a bit stretched out reaching the bars. I bought the 58cm frame which has a 110mm stem. Smaller frame sizes of the same model have less long stems so the bike people can get shorter ones from Specialized if I feel that is needed after getting used to it. I think you can go the same route.

Here are the geometry figures for your bike showing the different stem lengths.

http://www.specializedconceptstore.co.uk/Detail/19/allez/2010%20ALLEZ%2016

Have fun.

 

[youngoldbloke]

12' stem if you want to replace with a Specialized. I would think a 10' one would be fine though, and there is a huge choice - and at less cost from Wiggle, Ribble etc.

 

[MacB]

Aha, stems and reach this site is very good for comparison purposes:-

http://alex.phred.org/stemchart/Default.aspx

it's a calculator that lets you put in your existing setup and compare it to an alternate stem, it shows the difference it will make in height and reach. It also allows you to mess about rearranging the spacers. You need to know stem angle, length and headtube/steerer angle.

For example, if you currently have a 110mm stem, +12 degree, the Spesh Allez head angle should be 73.5 deg, I think you have to put in round numbers so use 73 degrees. I'll assume spacers of 30mm for this, a 100mm, +10 stem would reduce the reach by 7mm and the height by 8mm. Whereas a 100mm +20deg would reduce reach by 16mm and raise the height by 7mm. You can get stems angled up to +35 deg.

Another example, a straight swap for a +35deg, 110mm stem would reduce reach by 29mm and raise the bars by 34mm. However you could remove spacers from under the stem, if you have any, to refine further.

Don't forget that different drop bars have different reaches as well, you can get bars with as little as 50mm reach and as much as 100mm. That's the sweep forward from the flats to the bends, the normal seems to be about 80mm.

Personally I'd get someone to help you do the measurements for this site and input them:-

http://www.competitivecyclist.com/za/CCY?PAGE=FIT_CALCULATOR_INTRO&INTRO_LINK=NOREDIR

it'll give you a range of 3 fittings depending on the sort of riding you do. Most useful for me was that it gave ranges for saddle setback from BB, saddle nose to bars and saddle height from BB. It's not spot on but at least gives you parameters to work within and hopefully avoid spedning dosh on bits that will never work.

 

[youngoldbloke]

Chapter and verse from MacB

- just an aside - "Fits standard 25.4mm oversized handlebars and standard 1 1/8 fork steerers" - quoted from the description of the Halfords adjustable stem linked to by irw. Beware Halfords! Oversized bars are 31.8mm diameter!

 

[rockyraccoon]

I thought about the adjustable ones (incl. specialized) however the I don't find the price very attractive.. CCR is selling quite a few under £15.. I just need to decide the right size.

... The 58cm frame was great to pedal, but I felt maybe a bit stretched out reaching the bars. I bought the 58cm frame which has a 110mm stem. Smaller frame sizes of the same model have less long stems so the bike people can get shorter ones from Specialized if I feel that is needed after getting used to it. I think you can go the same route...

Sorry! I didn't understand it. Did you replaced the 110 mm stem or are you still using it? I have been cycling for a few months now but I still cannot get used to it. My road bike is also size 58cm.

... this site is very good for comparison purposes:-

http://alex.phred.or...rt/Default.aspx .... Personally I'd get someone to help you do the measurements for this site and input them:- http://www.competiti...RO_LINK=NOREDIR

it'll give you a range of 3 fittings depending on the sort of riding you do. Most useful for me was that it gave ranges for saddle setback from BB, saddle nose to bars and saddle height from BB. It's not spot on but at least gives you parameters to work within and hopefully avoid spedning dosh on bits that will never work.

Thank you very much for that.. I have already used the competitive cyclist website and found very useful. I decided to go for the Eddy Fit. I set my bike within the range recommended. I felt more comfortable when riding.. The site recommends stem length between 10.7 and 11.3. However, I still think I could go with a shorter one (100mm or 90mm). From the stem calculator website, a 90mm angle=6 gives me pretty much the reach reduction I am aiming; just around 13mm.

Would a change from 110mm to 90mm be to dramatic to the point which the length of the stem might affect handling? I read somewhere that a shorter stem makes more twitchy especially when riding fast. However for general cycling it gives a faster steering response..

Has anyone ever replaced a 110mm stem with 90mm one?

 

[MacB]

I had similar thoughts when I was messing about with stems and it's quite hard to get proper info on this on the web. Basically I was trying to find out what length stem constituted normal and what was considered to be at the extremes, in either direction. My best guesstimate is anything under 80mm, or over 120mm, is getting into the extremes, or certainly for a relaxed road style fit. My limited understanding is that longer stems became popular via racing. Allows a smaller frame and more leverage for sprinting, climbing, I think Mark Cavendish had a 150mm stem last year. I've ridden the same bike with a 35deg 90mm stem and a 120mm 6 deg stem, same bars and saddle position. I can't say I noticed any particular difference in the handling, but I'm not the sensitive sort. There's also the theory that, when on the hoods the front hub should be hidden by the bars, but it may be on the tops, someone will be along to clarify.

Same as you I found the closest match was the Eddy fit, with a bit of tweaking, another good resource is Dave Moulton:-

http://www.prodigalchild.net/Bicycle6.htm

I found that after I'd done all sorts of other stuff and his recommendations are pretty much spot on, just remember the geometry he's basing it on. It's fairly easy to adjust the numbers if your frame geometry is different, the angles of seat tube and head tube make a difference to the reach. If you take two frames:-

1. ST angle 71deg, TT effective 570mm
2. ST angle 73 deg, TT effective 560mm

Make the saddle to BB relationship the same on both and bike two will have a longer reach, by approx 10mm. This is because a longer TT, with a slacker seat tube, puts more of the TT behind the BB. In order to utilise the longer TT you'd have to set your saddle further back. Several manufacturers now show 'reach' as part of their geometry charts. They measure this in the same way as effective TT but taken from a point vertically above the centre of the BB.

I think you can tell I've just been spending time setting up a new frame and agreeing the specs on a custom one

 

[slowmotion]

Sorry! I didn't understand it. Did you replaced the 110 mm stem or are you still using it? I have been cycling for a few months now but I still cannot get used to it. My road bike is also size 58cm.

Sorry RR, I didn't explain myself well. I paid for the Secteur last Saturday, and it is still at the bike shop, for reasons that are too complicated but have nothing to do with cycling.
The guy at the shop and I both agreed that, since I was a stranger to road bikes, and would have to become used to one, it might be best for me to buy the 58cm frame size and see how I felt after a couple of weeks. (The 56cm frame felt far too small as regards comfortable pedalling, but good for arm position.) If I still felt a bit stretched out after that, I might try a shorter stem from Specialised or whoever. The 58cm frame comes with a 110mm stem, but there are 100, 90 and smaller ones available. The shop experimented with different angles, but that went way over my head.

I'm a complete newcomer to this! MacB knows more than I do...way more!


Best wishes

 

[Banjo]

I thought about the adjustable ones (incl. specialized) however the I don't find the price very attractive.. CCR is selling quite a few under £15.. I just need to decide the right size.



Sorry! I didn't understand it. Did you replaced the 110 mm stem or are you still using it? I have been cycling for a few months now but I still cannot get used to it. My road bike is also size 58cm.

Thank you very much for that.. I have already used the competitive cyclist website and found very useful. I decided to go for the Eddy Fit. I set my bike within the range recommended. I felt more comfortable when riding.. The site recommends stem length between 10.7 and 11.3. However, I still think I could go with a shorter one (100mm or 90mm). From the stem calculator website, a 90mm angle=6 gives me pretty much the reach reduction I am aiming; just around 13mm.

Would a change from 110mm to 90mm be to dramatic to the point which the length of the stem might affect handling? I read somewhere that a shorter stem makes more twitchy especially when riding fast. However for general cycling it gives a faster steering response..

Has anyone ever replaced a 110mm stem with 90mm one?

I swapped the 110mm stem on my scott Speedster for a 70mm stem initially as the position was giving me back pain. After a few months I put the 110 back on and found it ok.

It takes a long time to get used to the ride position of a road bike if your not used to it.I rode with the 70mm no problem so would say a 90 will be fine but keep the original stem as you may wish to put it back a few months down the road.

 

[rockyraccoon]

... but keep the original stem as you may wish to put it back a few months down the road.

thanks everyone for the comments! Very helpful. I understand a lot more now and I getting close in choosing the "right" stem. You're correct Banjo! It does take time to get used to the ride position also our flexibility improves over time. Cheers.

 

[Banjo]

One of these would raise your bars quite a bit if you needed it to.

If you want to try it I have a 90mm one in the shed I could lend you. It is for 31.8mm oversize bars 90mm long with 35 degree rise.

I keep it incase my back ever plays up again but havent used it for ages now so you are welcome to borrow and try it if you want to.

 

[rockyraccoon]

If you want to try it I have a 90mm one in the shed I could lend you...

According to the calculator your stem would reduce the reach by approx. 1.5 inches. That is 3 times more than I need. I think it'd be to short for me.

However, I want to thank you for that, Banjo. I's very nice of you.

 

[Banjo]

No probs,

its surprising how long it takes to get a road bike how you like it. I am on the third stem and spent about six months tweaking the seat fore ant aft position, even longer getting the angle of the drop bars just right. All feels comfortable at the moment .Its just the rider needs a bit of tweaking/upgrading now .

 

[Deleted member 1258]

The old fashioned way of checking stem reach was to put the back of your elbow against the nose of the saddle and your hand down the side of the stem, if your fingers touched the back of the bars the reach was about right, if your fingers didn't reach the bars the stem was to long, if your fingers went over the bars the stem was to short. Its a method I've used for years and its normally managed to get the stem length right first time.