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PostPosted: Thu Jul 24, 2014 8:03 pm 
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Location: Bremerton, WA
Hello all. I have been thinking about how to make my TT bike lighter. As of right now I'm scared to even weigh it because it is so beefy, but I am sure it is at least 20 lbs (9 kg).

Anyway, my first thought was to remove the rear brake entirely, including the lever up front. Not only would this drop about 200 grams, it would also improve the aerodynamics at the rear of the bike. I doubt I would really miss it considering most time trials are dead flat, and when they aren't, they don't usually include technical descending.

I had also considered removing the little ring and front shifter. This would save a bit less weight, and the aero gains would most likely be negligable. I am a bit more hesitant on this one because I do use the little ring when climbing with this bike (training rides), but I doubt I'd miss it during races.

Any thoughts? Advice on how to remove more weight and/or aero drag?

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PostPosted: Thu Jul 24, 2014 8:18 pm 
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Location: Istanbul, Turkey
The single biggest place to improve aerodynamics is your own position on the bike, I will not go over that.
I would advise against removing the rear brake. IMO the most important point of having two brakes is redundancy, if one fails somehow, you can still stop with the other. (happened to me once)
You could remove the small ring, FD and related hardware and save some weight. Putting it back on for a hilly TT wouldn't be much hassle.
Aero bottles are a good way to improve aerodynamics. Two bottles mounted close to the BB will help reduce the turbulence over that area and make you faster. Even a round bottle mounted on the seat tube close to the BB will help.
If your bike does not have an integrated (i.e. not flush with the top tube) stem, you could mount a storage compartment on there. That's UCI illegal though.
Having tyres that sit flush (i.e. not bulb shaped) will reduce turbulence on the wheels. Think 25 mm tyres on Zipps vs. narrow box section rims.
Hope this helps.


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Posted: Thu Jul 24, 2014 8:18 pm 


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PostPosted: Thu Jul 24, 2014 8:20 pm 
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it would be helpful if we knew what parts are currently on your bike...

your two ideas seem a little extreme...


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PostPosted: Thu Jul 24, 2014 8:31 pm 
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Location: Bremerton, WA
I suppose I should clarify my situation a bit. Most of the reason it is so heavy is because it has cheap anchor wheels and components, but I am planning to remedy that so I can use it with my race wheels (replace shimano bits with campy bits). That alone should save a big chunk of weight and get it down to reasonable levels.

I am aware that my position on the bike is the biggest aero factor, but that isn't what this thread is about.

I would say removing the rear brake on a TT bike is a lot less extreme than removing it on a hill climb bike, which I have seen other forum members do. I generally don't ride down any hills on this bike that require ANY braking, so I don't think it is incredibly dangerous. However, I could imagine being in a pickle if the single brake failed in traffic. I have personally never heard of anyone's brakes failing though. (snapped cable?)

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PostPosted: Thu Jul 24, 2014 9:07 pm 
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Location: Istanbul, Turkey
ITTY wrote:
I am aware that my position on the bike is the biggest aero factor, but that isn't what this thread is about.


Yup, I know.

ITTY wrote:
I would say removing the rear brake on a TT bike is a lot less extreme than removing it on a hill climb bike, which I have seen other forum members do. I generally don't ride down any hills on this bike that require ANY braking, so I don't think it is incredibly dangerous. However, I could imagine being in a pickle if the single brake failed in traffic. I have personally never heard of anyone's brakes failing though. (snapped cable?)


Yup, aged front brake cable snapped. Was able to skid to 5 kph and unclip before bumping into a car.




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PostPosted: Fri Jul 25, 2014 11:32 am 
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Location: Greater Pittsburgh
There's no problem getting a TT/Tri bike to somewhere around 16lbs with some careful planning. Wheels makes a huge difference, both from weight and aerodynamics, so look into options there. Replace the brakes with TriRig Omega's (works great both for front and rear), reasonably light, but very aerodynamic. If Easton Attack TT aerobars work for you, then you can really save a lot of weight there (there's commonly 2-300gr lighter than what they replace), not a lot of adjustability though, so only use if they fit you.

I suspect that the frame you have is quite heavy, so that might be a place to look as well… although that could be a quite costly proposition.

Oh, forgot to add… if you plan to race, you are required to have two brakes, so removing the rear is a no-go.

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PostPosted: Fri Jul 25, 2014 4:32 pm 
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Oh I did not know I was required to have 2 brakes to race it. Good info! Afterall, the only reason I got a TT rig was for stage races and ITTs (definitely not a tri-guy). I guess that eleminates that idea.

Yes, the stock wheels are outrageously heavy. Based on the front wheel weight of 1400g with tube/tire/skewer, I assume the wheelset is well above 2000g. Could also go with some supersonics and better tires.

I've been interested in the Omega brakes since they were first concieved, but I am pretty reluctant to try out the first iteration of any product, especially when it is such a small operation. I know they have upgraded/changed a few little bits and pieces on the brakes over the time they've been out. Anybody have any extended experience with them?

I like the look of the Easton Attacks, especially since I've been wanting a slightly lower position (non-integrated stem), and I've seen a lot of imitations on ebay. I'll keep my eye out for a deal.

The frame is a Scott Plasma 3 from 2013 (I think), and I'm sure it is plenty heavy, but I'm happy with it for now.

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PostPosted: Fri Jul 25, 2014 11:41 pm 
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There is little stuff, like lightweight skewers and cables. Trim your seatpost if its really long.

Light tires and tubes make a lot of sense.

Keep your brakes on, but maybe checkout the vision or 3t brake levers.

Aerobar can be a good place To cut weight.

Likely if you're on a plasma 3, there is not a lot of aero improvements to be had other than clean cabling and a good aerobar.


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PostPosted: Sat Jul 26, 2014 1:01 pm 
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Location: Greater Pittsburgh
Between myself and my wife, we've been using the TriRig Omega brakes for fronts from the very first release of them. Don't over think the improvements they've made, they're incremental and nothing earth shattering. The stopping power is just slightly less then the Campy Record caliper it replaced, so very good. All in all, a very well engineered brake.

The Plasma 3 if not that heavy for being an UCI legal frame…. could you put together a build list of the bike as it stands today? There must be some places where the weight add up...

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PostPosted: Sat Jul 26, 2014 1:42 pm 
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Location: Istanbul, Turkey
If you bought it as a complete bike, the wheels are boat anchors. Scott uses mostly aluminum components in complete bikes. Maybe an FSA crankset, depending on trim level.

But without the build list, I'm just speculating...


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PostPosted: Sat Jul 26, 2014 4:13 pm 
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I meant to say that I wouldn't change over to the omega unless you're really looking for those last few seconds, it maybe more aero than other brakes, but even tririg's tests state the time saved as 5 seconds in a 40k tt.


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PostPosted: Sat Jul 26, 2014 5:30 pm 
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Joined: Sat Oct 12, 2013 12:59 pm
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If you want to exchange aerobars and drop some serious weight on that, you should definitely check out the HaeroCarbon H.253 bar. Lightest set I have seen so far with 330g including extensions and pads.
What I also really love is skateboard griptape on the extensions and handlebars. It's light, it does not add much to the frontal surface of your bike, grip is fantastic and you can manicure your fingernails on the bike :mrgreen:. It is actually definitely not as bad as it sounds, give it a try.

Dropping the rear brake is for sure not a great idea, especially as it does not change a lot about aerodynamics mounted at the bottom bracket.

According aerodynamics:
- check your cable routing and make sure that everything is out the wind (for sure not a huge benefit, but hey, it's free :wink: )
- tape over any holes or edges you can see (not really sure about UCI-legality here...)
- get your arms as narrow as possible without restricting breathing (this is about position on the bike, but often overseen)
- wear a tight fitting outfit, no gloves, overshoes
- are aerobottles UCI-legal?

Those are small effects, but they add up.

The guys at tririg built a 12.9 lbs timetrial bike (http://www.tririg.com/articles.php?id=2 ... t_Tri_Bike). Maybe you can snatch some ideas from them ;)

Mine is 20 lbs/9kg aswell, but that includes a 50mm frontwheel, a disc in the back and a power2max powermeter with havyass aero-qrings (that alone is 1.2kg including pedals :shock: ). But I haven't focused on weight so far...


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PostPosted: Sat Jul 26, 2014 10:37 pm 
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Location: Istanbul, Turkey
My mistake, most aero bottles are illegal.


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PostPosted: Sat Jul 26, 2014 10:53 pm 
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The Elite Crono bottle is still UCI-legal.


Image


I have a very light TT bike. Shiv frame, USE R1 bars, a lll Di2, Lightweight Autobahn disc wheel, Zipp 808 with Extralite hub, seat post cut down, Berner cage, Fizik Tritone saddle with carbon rails, SRM with Rotor arms, Keo Blade 2 pedals with ti spindles.

Approximate weight: 7.2kg


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Posted: Sat Jul 26, 2014 10:53 pm 


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