I’m looking to move toward a slightly more aero/tri focused position with my road bike but I need some help in determining which parts will help me make the adjustment without throwing off my fit on the bike.
So here are the current measurements of my road bike setup (Note: These are the measurements given to me from my LBS when I got fit on the bike and I’m not 100% sure what some of the measurements mean so there is my disclaimer if something doesn’t make sense):
ST 56cm virtual 48cm CTC
TT 56.5cm
Reach 69cm CTC
Nose to center 55.5cm
Crank 172.5
Stem 120mm 35 degree rise
Handlebar 42cm CTC
Drop 70mm
I’m hopefully in the process of buying the Profile Design Carbon X base bar that Paulo is selling and I’ll need to select the aero bars to attach so I’d love some thoughts/advice on that decision. The stem length on his base bar is 120mm which is the same as my current road setup, the Carbon X is also available with a 100mm stem, what are your thoughts on which would be best for my situation?
Then add to the equation the possibility of getting a Fast Forward seat post or something similar, how should that influence my decisions? Also, I’m assuming that I’ll probably need to get re-fit on my bike by my LBS once I’ve made these changes, is that an accurate assumption? Any help is appreciated!
These dimensions are totally irrelevant without knowing your body dimensions, and even then it’s impossible to visualize over the net.
I’d stay away from the base bars on a road bike and keep the drops. Don’t get a fast forward seat post as it will put your weight too far forward and screw up the bike handling. Get a neutral set back seat post and don’t exceed 75/76 degrees of effective seat post angle. Push the seat a bit forward with the neutral post and you’ll be in the ball park. You can then lower the drop bars by a few spacers and add aero bars. You still don’t want too long aero bars as you’ll be too stretched out. Get a medium size bar or better yet, one that is adjustable for length.
I can’t help you with the numbers and fit but you can put base bars on a road bike. I just finished putting Vision Tech bars on my road bike and I love it!
These dimensions are totally irrelevant without knowing your body dimensions, and even then it’s impossible to visualize over the net.
I’d stay away from the base bars on a road bike and keep the drops. Don’t get a fast forward seat post as it will put your weight too far forward and screw up the bike handling. Get a neutral set back seat post and don’t exceed 75/76 degrees of effective seat post angle. Push the seat a bit forward with the neutral post and you’ll be in the ball park. You can then lower the drop bars by a few spacers and add aero bars. You still don’t want too long aero bars as you’ll be too stretched out. Get a medium size bar or better yet, one that is adjustable for length.
Yeah I know that the dimensions have very little value over the net, I just thought that given a proper fit with those dimensions perhaps someone could extrapolate what I would need as far as changing the bars and seat angle. It was a long shot but I thought it was worth asking.
As far as aero bars go, a number of people that I ride with have base bars on their road bikes and really like it so that’s why I was thinking of going that route myself. Also, you mentioned staying away from longer aero bars because I’d be “too stretched out” could you explain the rationale behind that thought? I would have assumed that I’d want to be as stretched out as possible while still being “comfortable” and maintaining optimal power output; does stretching out the torso reduce power output?
You don’t want to be too stretched out because it puts strain on your neck and shoulders resulting in fatigue and discomfort.
On a road bike you’re riding at a slacker seat angle(72-74) compared to a tri bike (78-80). This means that the tri bike generally has a shorter top tube, hence longer aero bars than the shorty road geometry aero bars that the ITU racers use on their road bikes in the draft legal Olympic tris. I’ve suggested a half way “multisport” position on your road bike, so you need a medium length aero bars to be comfortable, unless you have unusually long arms.
I’d suggest you read the articles on the main Slowtwitch page dealing with bike fit. Also Tom Demerly’s articles on his Bikesport website. Another very good source that talks about positioning is chapter three in the book “Zinn and the Art of Triathlon Bikes” by Leonard Zinn. Should be able to order or pick up a copy at your local bookstore.
The reason I’ve suggested keeping the drops/STI is because then you can still use your road bike for group rides, etc.
I rode tri bikes for five years and have recently switched to a similiar position as described on a Kestrel Talon.
Thanks for the explanation about being too stretched out. My current road bars are larger in the center where the stem attaches and then taper down from there, the problem being that if I were to try to put clipon aero bars on they would be pretty far apart, thus negating a bit of the desired aero effect. So that’s why I was thinking that I could just switch to a base bar but now i’m feeling conflicted. I guess what I’ll do is just pick up the PD Carbon X base bar from Paulo for $45, throw some aero bars on it and use it as a relatively cheap experiment, I can always sell it later. Any specific recommendations as far as seat post goes to achieve that happy balance of stability and efficiency?
Any correct size neutral seatback seat post will do fine. I sold a used Bontrager on ebay for $20. awhile ago.
If you look at dual purpose road/TT bikes like the Kestrel Talon and Cervelo Soloist, they have a dual position seat post. These are road geometry bikes with aero tubing that can be set up at about a 76ish effective seat angle for tri/TT. The neutral seat post with a the seat slid a bit forward will give you the same thing on any other road bike.
I modified my road bike to ride time trials years ago. At the time I could not afford a dedicated time trial frame. Here is what I learned in the process.
If you just slap most aero bars on most road bikes you will obtain a stretched out position that will usually be uncomfortable after some short time and will compress your breathing and ability to sustain your effort. In this situation you may be aero, but you can’t ride fast for very long.
To counteract this “stretched out” position, I used a forward seat post to move my saddle forward about 2.5 cm thus effectively shortening my top tube length. Profile Design makes a Fast Forward seat post and Thomson makes a “relaxed” seat post that can be reversed to move the seat forward rather than rearward. I used the Profile Design Fast Forward seat post.
The next thing you can do is use aero bars that allow you to move the arm rests and hand positions fore and aft without regard to where the base bar (handlebar) is. Profile Design makes a number of models that allow this such as the Jammer GT bars and the Wing Clip kit. I happened to like the Split Second bars that did not allow moving the arm rest pads but but did allow moving the hand holds fore and aft. This set up did not cause issues in my case and I found it very workable.
Know, that as you make these modifications your bike will become less stable (more twitchy) at low speeds. As you ride faster, your bike will become more stabe for multiple reasons. One, it wants to keep going in the direction it is already going and you also get a gyroscopic effect from the spinning wheels. You really need to be able to ride faster than 20 mph ave., however, for these effects to really benefit you.
can you recommend a set of short and/or adjustable aero bars that would mount up to the Carbon X base bar I got from Paulo? I’m watching seat posts on eBay…
You don’t need the shorty bars unless you’re planning on keeping the bike in the road position. If you’re going to modify to the “multisport” position I’d suggest a basic aero bar that offers a lot of adjustment and is quite comfortable. Something like the Profile Aerolite comes to mind. Go on the Profile Design site and you’ll note that they make a number of different models that have a fair amount of adjustment. It boils down to how much money you want to spend, but remember that carbon aero bars aren’t any faster than aluminium.
What I’m thinking is that I’ll have two setups for my bike, one multisport and one road, I’ll just swap out the parts as needed (hopefully not frequently!). For the multisport position do you still think that I should just get a zero setback post or should I go for a fast forward or similar to move me forward in the aero bars?
I did a setup similar to your description on my Talon for most of this past year. It seemed to work pretty well for me, but I did notice a decrease in handling. I got used to the handling pretty quick and it wasn’t a big deal to me as most TT’s and tri’s aren’t as demanding as screaming downhill through turns with a group. I used a Fastforward seat post and Profile T2+ bars and profile base bar. I had an effective seat angle of 77° and a hip angle around 97°. The position seamed to work for me as I had some of my best TT results ever this year. That said, the setup always felt a little contrived. The down sides were that my cockpit was closed up (knees hitting my elbows) and my bike didn’t climb that well.
Towards the middle of the summer I was able to get a new Felt B2 - man what a difference. I’m now able to ride in the same position on a bike that already has the correct geometry. The handling is much better, no more elbow hits, and it climbs wonderfully.
Do what you have to do for a while. When you have the funds, I would recommend getting a specific TT bike. Otherwise, I have all the parts mentioned above for sale. PM if you’re interested.
This is exactly what i did on my Specialized Allez so i could have a compact frame that travelled well, and for hilly races. I used a Thomson Elite zero setback pst with a Fizik Arione pushed up about 1cm forward of center. Then I used a really simple PD clip on (T2 Cobra) with short extensions.
It was pretty good. I’d be really leery of going more forward and leaning more weight on the front end than i was. I suspect a FF seatpost may suck on a lot of bikes. But i guess it depends on the bike you are starting with.
A couple of things - the fast forward post puts you more forward than the dual position Kestrel aero post does. Why use it instead of the Kestrel aero post that was designed for the bike?
The Soloist/Talon type bikes work fine in the 75/76 position and are a great option for people looking for either a dual purpose bike or not wanting to ride excessively steep. Considering how many tris Macca won on a Talon or Lessing winning IMLP on a Soloist, anybody who says they don’t make good tri bikes is missing the point.
What they don’t do is make good steep angle tri bikes. That’s not what they were designed for.
Cool, thanks for all the input guys, this has been immensely helpful for me! I just won a zero setback seat post on eBay so that’s the direction that I’m going with it. Now it’s just a matter of aero bars, brake levers, bar-end shifters, and something to replace my road saddle.
