Aero/Gains Thread

Soldato
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Ordered some USE 50deg extensions this morning. Currently using Specialized 40deg reversed, so these will be going on in the same manner. I'll be dropping the front end to the lowest point too (only something like 10mm to go down). Looking out for a single narrow wide bigger front chainring too to get a straighter chainline as I usually grind out a TT at low 80s cadence.

Nice :) What arm rests are you on? If not on angled then would recommend that. you'll definitely feel benefit of angled with such high degree bars when fitted.

What size chainring?
I'm on the 54t single Fiberlyte and would recommend ordering from them if buying new as you'll get something exact. I am now thinking I should have went with a 56t though :(
A few lads about here on the Pyramid Design 58t and I have to say I am impressed and would gladly have one. So worth a look too :)
 
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Nice :) What arm rests are you on? If not on angled then would recommend that. you'll definitely feel benefit of angled with such high degree bars when fitted.

What size chainring?
I'm on the 54t single Fiberlyte and would recommend ordering from them if buying new as you'll get something exact. I am now thinking I should have went with a 56t though :(
A few lads about here on the Pyramid Design 58t and I have to say I am impressed and would gladly have one. So worth a look too :)

Already got some of the little shims from TT forums for my standard arm rests. They'll be fine for the extra 10degree for now, then go from there.

I'm thinking a 54 oval or a 56 standard. For a vision trimax carbon so ideally want something that looks as snazzzy as the current all in one design. Think 58 may be too much for me, but power is on the up so may do. Will see what comes up.
 
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Well after seeing some photos this weekend, my head still sticks up but my arms being more angled defiantly helps.

I can’t adjust my arm rests due to drilling too many holes in them to lighten them (made them from 3mm steel plate after the alloy ones cracked!).

Looks like I’ll have to go to an adjustable front end. I like the bullhorn style base bar, but need an adjustable up top while I refine my position.

Any recommendations? Or just buy some arm rests with lots of mounting positions and then use them on a bar upgrade at a later date?

Zipp Vukas are easily the most adjustable bars I’ve used, great for tweaking position.
 
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Just get on tt forum and pick something up cheap to get you going before spending serious cash on something all carbon once your position is settled.
 
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Already got some of the little shims from TT forums for my standard arm rests. They'll be fine for the extra 10degree for now, then go from there.

I'm thinking a 54 oval or a 56 standard. For a vision trimax carbon so ideally want something that looks as snazzzy as the current all in one design. Think 58 may be too much for me, but power is on the up so may do. Will see what comes up.

I was on 53 Q Ring (which I had tried previously on road bike and was convinced of switching to....) but could not get used to it at all on the TT bike in that position. Very happy being back to round chain ring so just be weary that you may be opening a little can of worms of hassle in finding your happy place :p

The 2x guys I know with single 58t pyramid designs are both 12KG heavier than me and are doing 270-290w for 10's. They were both VERY apprehensive after Dan Bingham convinced them to just got with a 58t. But they are both now saying it's fine and no as dramatic as may first appear. If you check the ratios out a 58t isn't that dramatic either and actually looks pretty good. I think one paired with SRAM 11-26 cassette will be optimal for flat 10's/25's..... I'm tempted!
 
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I was on 53 Q Ring (which I had tried previously on road bike and was convinced of switching to....) but could not get used to it at all on the TT bike in that position. Very happy being back to round chain ring so just be weary that you may be opening a little can of worms of hassle in finding your happy place :p

The 2x guys I know with single 58t pyramid designs are both 12KG heavier than me and are doing 270-290w for 10's. They were both VERY apprehensive after Dan Bingham convinced them to just got with a 58t. But they are both now saying it's fine and no as dramatic as may first appear. If you check the ratios out a 58t isn't that dramatic either and actually looks pretty good. I think one paired with SRAM 11-26 cassette will be optimal for flat 10's/25's..... I'm tempted!

I went with a 56t Fibrelyte and think a 58t would definitely be fine for racing. I train on the 56t and an 11-28 cassette. I studiously avoid hills but it's fine for endurance paced stuff on the flat.
 
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I was on 53 Q Ring (which I had tried previously on road bike and was convinced of switching to....) but could not get used to it at all on the TT bike in that position. Very happy being back to round chain ring so just be weary that you may be opening a little can of worms of hassle in finding your happy place :p

The 2x guys I know with single 58t pyramid designs are both 12KG heavier than me and are doing 270-290w for 10's. They were both VERY apprehensive after Dan Bingham convinced them to just got with a 58t. But they are both now saying it's fine and no as dramatic as may first appear. If you check the ratios out a 58t isn't that dramatic either and actually looks pretty good. I think one paired with SRAM 11-26 cassette will be optimal for flat 10's/25's..... I'm tempted!

Thanks, I run oval on my CX bike and didn't even notice the difference, will see what comes up, running 11-23 equivalent on my TT as the Super9 fouls my oversized jockey wheels cage due to the width, so the limit screw is set to be unable to change into the 25 gear. I'm also limited as my super 9 is campag hub (350quid cheaper) so don't want to be buying any new cassettes either :D

Will look out for a 58, trying not to spend millions as I want to get a new CX bike for next season.
 
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You can get Ultegra 11-23 11 speed cassettes, no more nasty gaps (gains you an 18). Doesn’t help you though solid!

I’ll just hold fire and see what bars come up second hand.

The Selcof are £199 at Planet X but allegedly discount down to £149 fairly regularly.
 
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Looking for neutral input on this as it's frying my brain....
Nat 25 (Scotland) I done a 54:37 off 294w. Data showing my cda as .209 from MyWindSock Premium and I can get very very close to that in Aerolab. So it's not far away! This was at 61KG myself, bike at 8KG and let's allocate a high 2KG for kit. 71KG total.
Lad next to me I was chatting to done a 52:14 off his claimed 293w. He's on Garmin Vector2's and I was on Vector 3's which are reading identically to the Vector 2's I replaced them with only 2 weeks ago!
He weighs 71KG taken from what he said to me at the event. Let's give him 10KG on top, same as me, for bike and kit so 81KG total.

It's a MASSIVE time difference for same watts. Possible power meter variance but I am doubtful. His PWM would be under reading heavily if the case. Mines checks out against my previous PWM and my smart trainer.
Other thing is his cda is of Tom Dumoulin levels!

Is there any correlation to heavier weight carrying more momentum or weight = higher maintained speed at set output?
This game baffles me sometimes :(
 
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Looks like it was Graham smith going by the comments?

I ride with Graham all the time and when it's him and big Dougie sticking the boot in it hurts like ****!

Strava stalking it looks like he put 30s into you on the way out - tailwind? then on the way back put 1:05 into you which if he is pretty aero it will make a bigger difference into a headwind? Amazing what 1mph difference in average speed makes. I've heard of people that gauge efforts on drags and push harder on descents as you gain more speed for longer...

I reckon I did over 300w for my 23:35 10 but that power with an aero setup I'd be easy a minute quicker?
 
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Looks like it was Graham smith going by the comments?

I ride with Graham all the time and when it's him and big Dougie sticking the boot in it hurts like ****!

Strava stalking it looks like he put 30s into you on the way out - tailwind? then on the way back put 1:05 into you which if he is pretty aero it will make a bigger difference into a headwind? Amazing what 1mph difference in average speed makes. I've heard of people that gauge efforts on drags and push harder on descents as you gain more speed for longer...

I reckon I did over 300w for my 23:35 10 but that power with an aero setup I'd be easy a minute quicker?

Yeah it was Graham. First time I have talked to him and he's a proper sound lad. I appreciated him taking time to have a yap as usually its head down and nobody chats at these things.
Not for one second saying he isn't super strong as I have always known he is but numbers take over me at times when I look back. There was no tailwind either way really it was equal. Can see where he was faster in speed terms but watts are watts so it just gets me over thinking.
300w on full aero setup you'd be a load more quicker! Plenty lads doing 21's off way less watts than 300. Reckon you would love getting stuck into TT's Jonny :) Get some money sunk :p
 
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I would say a .209 CdA off MyWindsock is relatively high but it’s not an exact science. Did you adjust the Crr value or just go with the default? I know courses up there are quieter traffic wise but I’d have thought a race CdA of <0.19 should be achievable at your size @xdcx.

In terms of easy gains I’d be looking at shoes/shoe covers, helmet and reach. I benefitted a lot from closing the gap from elbow to knee by shortening my reach. How far apart are your arm rests too?
 
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@One More Solo - I reckon helmet is the next obvious one. Keen to test an Aerohead against my Bambino.
I tried slightly lowering CRR in Aerolab when I tried to come to a CDA for the guy who done 52 on similar power. I had to do so because at his weight and putting in an insanely low CDA it still put well over 53 mins. CRR had to be lower than default. So I lowered mine slightly also but I don't like knowing even a semi-accurate figure for this. Testing it is much more involved and cannot be exacted for race days anyway.
Arm rests are wider than I would want due to having my blip box mounted. I would actually be more comfortable (an more aero) with them very very narrow. I could only achieve this by trying to mount the blip box underneath my stem or by raising my arm rests. I am not wanting to raise them really.... The other alternative is to find or have arm rests made that are much smaller in terms of base. I like the high sides but I need only half of the base/platform size I have, they are way too big. So at least there are options.

@SoliD - Yes, more unknowns I am afraid. Other rider is Aerohead, Corima tri and disc with full cabled DA/Ulteg drivetrain.
I'm Velotec skinsuit (testing very well), Revolver FWS7 front with Corsa Speed and FFWD rear with a slow tyre. eTap for me and fresh waxed chain so DT is good. Helmet and rear tyre for me is obvious things to address I guess. Suppose I could be lowering my CDA and CRR quite a bit doing these and be surprised at how much time it will gain me.
 
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Yeah it was Graham. First time I have talked to him and he's a proper sound lad. I appreciated him taking time to have a yap as usually its head down and nobody chats at these things.
Not for one second saying he isn't super strong as I have always known he is but numbers take over me at times when I look back. There was no tailwind either way really it was equal. Can see where he was faster in speed terms but watts are watts so it just gets me over thinking.
300w on full aero setup you'd be a load more quicker! Plenty lads doing 21's off way less watts than 300. Reckon you would love getting stuck into TT's Jonny :) Get some money sunk :p

I'll preface this by pointing out that I'm rubbish at TTs and have no idea what I'm talking about:

I'd say the difference is nothing aero, just where and how you use your power.
Looking at the first 2.2 miles of the race (and assuming that your ride has the correct elevation profile because his is different and doesnt match up with the speeds).
hdR7q82.png
(you on the left, him on the right)
You've stuck strictly to your average power pretty much constantly whereas he has coasted down the hill a bit at under 200watts. You're ahead after this section (look at the total times taken rather than the average speed calculated by strava - i think the autopause or pickup time off the start line has messed that figure up a bit) but you've used 30watts more on average to get there. Drag increases exponentially with speed, so even though you were slightly faster down the hill, you've used a lot more power to do that.

Then look at the following 10 miles from this point to the turn.
lgxLDW2.png
(Again, you on the left, him on the right)

This is where he made up almost all of the time on you - there's not much difference in times on the return leg.
Having rested a little on the first descent, he is now putting out a bit more power (17watts more) on the flatter section which results in a higher average speed. You can see a small dip in power and increase in speed again where he takes a short break on a descent around 7 miles.
Overall, average power is not much different between the 2 of you but he the way that you've used the power is different. Conservation of momentum is the most important thing so pushing a little harder on the climbs and easing back on the descents.
 
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I agree with the above ;)

Wiggins explained it well on Eurosport when asked a similar question.

If you’re on the motorway in the car you almost subconsciously squeeze the accelerator a little more on lumps to maintain speed, you ideally want to do this in TT also.

Add a little power to get over a lump without reducing your speed and then you can ease a tiny bit on the other side, rather than holding threshold power, lose speed and then have to regain it again.
 
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Good analysis that touch, always try to tell people new to tt push hardest when you're going slowest. Whether that's into a headwind or going uphill.

As speed rises so does aero drag so getting the power down when it's hardest will give you the quickest times. Easier said than done though!
 
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