Last night I used the FIST protocol articles and did an at home fitting and confirmed what I suspected - my cockpit is too long by a couple of inches. Currently my bike (a 2006 QR Tequilo) has a 60 mm stem. I see that there are stems as small as 20mm yet I wonder how a stem this short will affect handling.
When do you stop shortening the stem and go to a smaller bike?
Can you post a picture of you on your current setup?
Can you post a picture of you on your current setup?
I’ll work on getting a picture posted, but here is how I came to determine my cockpit was too long: 1) the pain in the middle of my upper back that I’d get on long rides and 2) my shoulder angle was 95 degrees - not the 80 to 85 degrees suggested in the FIST article. My seat is as far forward as it goes, so shortening the cockpit by going steeper won’t work.
that thing has a rider limit of 90lbs. that tell you something?
A shorter stem (lever) will create the same angular change that a longer (lever, cockpit, stem) would with a shorter arc.
Hence your bike will become a bit more twitchy. although (depending on how comfortable your hand position is now) you could counter this by using longer extensions.
I am assuming that you are not as worried about the change in your pursuit bar position since it is a more stable control position.
that thing has a rider limit of 90lbs. that tell you something?
On second look that stem is for BMX bikes. For road bikes the smallest I can find is 50mm, only 10mm shorter than the one I have now.
A shorter stem (lever) will create the same angular change that a longer (lever, cockpit, stem) would with a shorter arc.
Hence your bike will become a bit more twitchy. although (depending on how comfortable your hand position is now) you could counter this by using longer extensions.
I am assuming that you are not as worried about the change in your pursuit bar position since it is a more stable control position.
This makes sense. Going with a shorter stem could make my bike harder to control. Is there a cutoff point where twitchy becomes dangerous? After taking another look at online bike stores and the lengths of stems offered, it looks like I am at the low end already with my 60mm and there are not many stems available in smaller sizes - for road bikes anyways.
50mm is the shortest commonly available. You can find 30mm if you look. My 2 cents is I’d get a professional to take a look at you before you buy a new frame. But if you are going below 50mm then you that bike doesn’t fit you.
What’s your base/aero bar setup like?
Aero clip-ons such as the PD T2+ can be moved forward and backward. Since the pads are mounted to the extension you can move the extensions back and keep the same pad-to-grip relationship.
This will have the same effect as a shorter stem. It will shorten the cockpit and probably add to the twitchyness.
Last night I used the FIST protocol articles and did an at home fitting and confirmed what I suspected - my cockpit is too long by a couple of inches. Currently my bike (a 2006 QR Tequilo) has a 60 mm stem. I see that there are stems as small as 20mm yet I wonder how a stem this short will affect handling.
When do you stop shortening the stem and go to a smaller bike?
How about some actual measurements so we can better understand what we are working with.
One thing you didn’t mention was what bar setup you are using. Bars can have a huge impact on cockpit length. Some bars mount the arm cups much farther aft then others. The rear of the arm cups on my Oval A700 bars are 1cm behind the centerline (measured through the stem) of the base bar while my HED bars allow for the arm cups to be moved as much as 7cm behind the bar centerline. Both of these bars offer adjustable extension to control the overall reach. Needless to accomplish the cockpit reach with these bars I need to use substanialy different stem lengths. ST really needs a database on Stack and Reach for different bars.
Definately sounds like your frame is too large. A 60 mm stem is quite short already. Normal stem recommendations are 90-120 as being optimal, although it’s not as critical on a tri/tt bike as a road bike.
How steep/slack is the seat angle? How far in front (or behind) is the nose of the saddle relative to the BB?
How about some actual measurements so we can better understand what we are working with.
One thing you didn’t mention was what bar setup you are using.
Tonight I’ll measure everything and fill out the bike fit info in my profile.
The bars are the stock bars that came with the bike. I’m having trouble finding the specs for older QRs online, but the bars are Visiontech brand and I don’t know the model number. They don’t seem to be adjustable.
Edit: The bars are Vision TT-bar by FSA. The pads can be moved to make them narrower, but they do not move forward or aft.
I agree that looking at different base bars may be an option. And although it could be an eaxpensive one. It is likely a pretty even wash with a new frame.
I also think a Database of aerobar data would be helpful.
One observation is that there seem to be a lot of 110 to 130 cm stems for sale in classifieds. It seems then that many people have found that their cockpits are to long. Perhaps it is a shift away from the (over)long and low position. ??
I agree that looking at different base bars may be an option. And although it could be an eaxpensive one. It is likely a pretty even wash with a new frame.
I also think a Database of aerobar data would be helpful.
One observation is that there seem to be a lot of 110 to 130 cm stems for sale in classifieds. It seems then that many people have found that their cockpits are to long. Perhaps it is a shift away from the (over)long and low position. ??
or product managers spec’ing poor combinations of stem length and bar type… as we all know a lot goes into dialing in the correct fit. Slowman has suggested that bike manufactures stop including saddles in higher end bikes, I agree and think that they should stop including stems as well.
Not a bad idea. Personally I like the frameset and pick your gruppo method.
So I measured my current setup and updated my profile. I’m note sure what this can tell anyone, but I estimate that the cockpit should be 3-5 cm shorter. I’d also prefer my seat to be a little farther back. Right now it is pushed to the most forward position so I wouldn’t be so stretched out.
- QR Tequilo
Style: Tri
Brand: QR
Model: Tequilo
Size: 57cm
A: Saddle height = 730
B: Plumb line, saddle nose to BB = +25
C: Cockpit (nose to extension tip) = 750
D: Armrests to extension tip = 355
E: Armrests drop = -90
F: Saddle nose to armrest back = 406
G: Armrest width = 245
I am going through this right now as well, went down from 110 to 80 stem, but also replaced my seatpost which had an off set allowing the seat to move forward some. At some point the bike doesn’t fit you, it’s a careful balance.
Replying from my phone so pardon the spelling.
Cockpit length looks ok but a pic would really help.
You are sure infront of the bb can you make power that steep?
Being that far forward I would like to see 130 or more of drop.
Arm cups look very wide. I would expect 200 or less would make you faster.
Again pics would help.
wow…you guys are awesome fitter!!!
this thread is worthless without pic…mesurement without pic dont do much…