TT bike vs Clip-ons

Pokerface

For those in the know - how much difference is there between a dedicated TT bike and a road bike with clip-ons?

The road bike would have a disc wheel on the rear. All usual aero bits still will be used (helmet, skinsuit, etc)


Reason I ask is - I have both bikes and have to travel to Spain to race, but can only take one bike so am looking at how much time using my road bike with clip-ons will cost me (over a 10 mile course).


Thanks!

jibberjim

Pokerface wrote:

For those in the know - how much difference is there between a dedicated TT bike and a road bike with clip-ons?

The road bike would have a disc wheel on the rear. All usual aero bits still will be used (helmet, skinsuit, etc)


Reason I ask is - I have both bikes and have to travel to Spain to race, but can only take one bike so am looking at how much time using my road bike with clip-ons will cost me (over a 10 mile course).

Depends on the position you'll get in both of the bikes. If it's identical, then the difference between the aerodynamics of the two front ends will be minor. However it's more likely that the position will be different, and in that case it could be lots, and it may not even be the TT bike which is faster.

Pokerface

jibberjim wrote:

However it's more likely that the position will be different, and in that case it could be lots, and it may not even be the TT bike which is faster.

That would almost be a relief as I could then sell my TT bike and make some money back!

Will have to wait for the clip-on bars to arrive, then go out and do some testing I guess.

Pokerface

Clip-ons will be with me tomoro and strapped to my road bike for my usual Wednesday night club TT. Will be interesting to see what sort of time difference (+ or -) I get.

kafkathedog

Did a test myself a couple of weeks back and was surpised to find myself going nearly 2 mins faster on my road bike over my TT bike.
Used the same wheels for both runs - Easton EA 50 SL


Possible reasons

1/ It was slightly windy when I did it on the TT bike, whereas on the road bike it was a still night.
2./ It was the first time out on the TT bike since september and couldn't get comfy.

So I have in fact sold my TT bike and am just going to get some clip ons for the road bike as this is the bike I am comfy on and do all training/riding on so it makes sense.
If I were quicker (and could be bothered to take TTing more seriously) then I would spend more time training on the TT bike and perfecting position.

My tuppence worth - take the road bike - over a 10 not going to lose much.
PB 23:50 for a 10

Pokerface

It will come down to comfort I think. I am used to riding my TT bike in the aero position. Not sure how it will feel on a road bike.

However - my road bike is lighter and I can see it being easier to get out of the saddle and power up the some of the uphill parts of the course where I normally sit and grind it out on the TT bike.


"Not losing too much time" is OK on the club TT - but the race in Spain is an international race and a few seconds (over the 13 mile course) could actually matter. A minute can mean the difference between first and last. And so on....

kafkathedog

If you are comfy and feeling good then IMO you should put out more power than if you are not*. In my case I just didn't spend enough time on the bike to make it worthwhile. The position was more aero for sure and when everything clicked I would go faster, just not enough faster to count, plus my road bike is stiffer than my older steel TT was.

In your case however as you say every second may count and I'm guessing you go a hell of a lot quicker than I do anyway and if you train/race regularly on it then who knows, depends on the profile of the course too i guess



*not a scientifically proven theory

Pokerface

kafkathedog wrote:

In your case however as you say every second may count and I'm guessing you go a hell of a lot quicker than I do anyway

That would be a negative. I most certainly don't go faster than you. But I race for the Paralympic team - so it's all relative.

SBezza

I think the TT bike would be faster, but as mentioned above it will depend on the position you can achieve on the road bike.

If it was for taking out to a race overseas, well that depends on what other riding you will be doing. If it is mainly the race and possibly a couple of other rides, then I would take my TT bike. If you were going to be doing mountain rides whilst out there as well, then a road bike with clip ons might be a better choice.

As for the hills, if they are just rolling hills, then the lightness of the bike is unlikely to make a huge difference.

For me if the race was important, I would take the fastest bike without a shadow of a doubt. I have used my TT bike on all my races no matter how hilly. I can climb on my TT bike just as well as a road bike, with the exception 39/21 is harder than 34/25.

Pokerface

It's a road race followed 2 days later by a TT. A road bike is a must - the TT bike is optional.


I won't be the only one using their road bike for both. If I go to the World's in August - I'll be taking both.

SBezza

In that case I would go with one bike, the road bike with clip ons, unless of course you really want to take 2 bikes.

Pokerface

The logistics of taking two bikes to this particular race make it nearly impossible. Most certainly impractical.

kafkathedog

there is your answer then, presuming of course you can't use your TT bike for the road race

Good Luck, let us know how you get on

Pokerface

kafkathedog wrote:

there is your answer then, presuming of course you can't use your TT bike for the road race

Good Luck, let us know how you get on

No - a TT bike in RR would be a giant no-no!

Thanks and will update!

Homer J

Good luck on what ever you ride

angrynortherner

http://www.cyclingnews.com/features/how-aero-is-aero

Here is a scientific study from Specialized on the difference between a TT Bike and a Road Bike.

Pokerface

Rode tonight in the club 10 with the clip ons. Went faster than last week, but not as fast as I have in the past. But, all in all - with a few tweaks to position and a bit more practice, the clip-ons will prove to be a more than adequate substitution for the full TT rig.

Probably lost the most amount of time overall just by having to move my arms just to change gears (and there are a lot of gear changes on my course as it's up and down).

I think overall - I lost some time on the downhill portions, but made it up on the uphill parts.

My TT in Spain will be hilly - so the road bike will probably prove to be a good solution.

Anonymous

I think you'd do better with it in Spain mate, you did well tonight!

rokkala

Pokerface wrote:

Rode tonight in the club 10 with the clip ons. Went faster than last week, but not as fast as I have in the past. But, all in all - with a few tweaks to position and a bit more practice, the clip-ons will prove to be a more than adequate substitution for the full TT rig.

Probably lost the most amount of time overall just by having to move my arms just to change gears (and there are a lot of gear changes on my course as it's up and down).

I think overall - I lost some time on the downhill portions, but made it up on the uphill parts.

My TT in Spain will be hilly - so the road bike will probably prove to be a good solution.

Encouraging to hear! This thread has just made me go buy some clip ons for my road bike. Got a cheap TT bike last year from a club mate but just can't get along with it, quill stem and some overcomplicated ancient aero bars that have the arm rests way too far apart for my liking.

On a slight tangent, the link posted earlier: http://www.cyclingnews.com/features/how-aero-is-aero

In that it says the difference between the road bike with clip-ons and the TT bike are around 19watts. Then goes on to say that standard road bike in drops vs road bike with clip-ons is a difference of 29watts.

Roughly how many seconds does that equate to over a 10mile TT? For the 19 & 29 watts.

Good luck in Spain!

Pokerface

Well - Mr. Nap D went 20 seconds faster tonight and had roughly 20 watts more power. But weather conditions always play a factor so converting wattage to real time is difficult to say.

And as for me - my road bike had a disc wheel on the rear and a Zipp 404 on the front, so it's probably closer to a true TT rig than the test mentioned in your post Rokkala.


But, if everyone (except NapD) went slower tonight than some of the previous weeks, then it will have been a revy good night for me as I was a bit faster than last week.

Jeff Jones

AngryNortherner wrote:

http://www.cyclingnews.com/features/how-aero-is-aero

Here is a scientific study from Specialized on the difference between a TT Bike and a Road Bike.

Ta for posting that. I actually wrote it with the BikeRadar format in mind, so the 'original' has more pics to illustrate the different positions:: http://www.bikeradar.com/news/article/h ... aero-19273

It was an interesting day for sure, although as others have said there are a few other factors to consider when choosing between a road bike + clip-ons compared to a TT bike. You need to train on the TT bike to fully adapt to the position. A lot of people don't do this, negating the benefit of it.