Road Cycling

Saytan · 30 Nov 2017 at 11:27

merlin said:
Power meter has arrived, hopefully get it set up tonight. How do single sided crank pwm's deal with leg imbalances? From last time I used a wattbike i think my left leg was 48% or 49%.

My understanding is that they take the figure for the leg they read and double it.

you could do some faffing around to generate slightly more accurate figures but at 48-49% is there really a major worry about that? it'll always be directly comparable to itself

merlin · 30 Nov 2017 at 11:32

Saytan said:
My understanding is that they take the figure for the leg they read and double it.

Ah, gotcha - yes of course that makes perfect sense.

I've got confused. I was reading something which I guess would have related to two sided pedal pwm's - reading up on balancing, and completely misunderstanding the relevance (or lack of it) to single sided crank meters.

SoliD · 30 Nov 2017 at 12:02

Big guns out today with my full length overbibs on, as Shamrock said it was such slow going all layered up, hopefully it's not this cold for Cross on Sunday! :S

Bear · 30 Nov 2017 at 12:27

merlin said:
Power meter has arrived, hopefully get it set up tonight. How do single sided crank pwm's deal with leg imbalances? From last time I used a wattbike i think my left leg was 48% or 49%.

Reading about the 4iii the other day and in the app you can set an offset so with 52/48=1.083 so thats your offset with the sign depending on right or left leg bias if I remember correctly (disclaimer: I may have remembered it wrong)

Roady · 30 Nov 2017 at 12:41

Had some fun last night... With my Zipp 30 Course wheels here figured I'd throw an old 32mm tyre I had on (Continental Sport Contact II) and with the wider rim it may fit under my existing guards, then I'd order some 32mm winter tyres (as not many options come in 30mm).

Combine the wire bead, cold weather and my wider rims (& feeble fingers?) I found it utterly impossible to get the bead over the rim. Thought to myself - I'll just whip the 28mm off my Diverge and at least try that... Due to the cold even that was a mission and I trashed 2 inner tubes trying to prise the tyre on with my levers. Once it was on I figured as I was already in the dog house as (my '20 mins in the garage' was already over an hour) I may as well mount the second disc and do the front wheel too and just ride my new wheels!

#procommuting xD

Wheels don't feel particularly fast, they're very comparable weight (1700g) to my old AXIS rims. Shimano RT86 rotors, heavy tyres and tubes.

I have got some fancy low weight disc rotors to use in the summer (Alligator Motion) but really figure I'll need to go tubeless to make a noticeable difference...?

randomshenans said:
Snowing on the way in. Was lovely.

Sweet! You didn't look that cold in your picture due to all of the 'winter insulation' you're currently carrying mate. #burned

Vonhelmet said:
-1 here in the North West. The ground was OK, but I was glad to be on the cross bike, even if it's just a confidence thing at this stage.

Seems similar to here then, frozen solid cars but roads and cycle paths clear. Some ice on puddles and frost on verges.

merlin said:
Power meter has arrived, hopefully get it set up tonight. How do single sided crank pwm's deal with leg imbalances? From last time I used a wattbike i think my left leg was 48% or 49%.

Deal? They don't, it can only measure the 1 leg and double the value. Just means with your variance your data will have ~8% variance to actual. Throw a PWM variance of typically ~5% in there and you'll stat to realise how futile directly comparing riders power figures are...

Saytan said:
it'll always be directly comparable to itself

This is the key thing with power & training with it. I found quite quickly that my power figures between smart turbo and PWM where totally different. If you're going to be doing FTP based training sessions on the road/track with your PWM you're almost best to do a different FTP test for them to your turbo...

Fusion · 30 Nov 2017 at 12:42

Cube arrived yesterday :cool:

. Only had time for a quick blast round local streets, keen to get out properly.

randomshenans · 30 Nov 2017 at 12:51

Roady said:
Sweet! You didn't look that cold in your picture due to all of the 'winter insulation' you're currently carrying mate. #burned

Fair. I was well prepared for winter

Bear · 30 Nov 2017 at 12:53

Roady said:
Deal? They don't, it can only measure the 1 leg and double the value. Just means with your variance your data will have ~8% variance to actual. Throw a PWM variance of typically ~5% in there and you'll stat to realise how futile directly comparing riders power figures are...

This is the key thing with power & training with it. I found quite quickly that my power figures between smart turbo and PWM where totally different. If you're going to be doing FTP based training sessions on the road/track with your PWM you're almost best to do a different FTP test for them to your turbo...

The people at 4iii are a bit smarter, they have an app that you can set an offset for leg imbalance if you know what it is to begin with.

Merlin seems to be able to get a good hour riding on track so he could do a proper FTP on track

Lethal` · 30 Nov 2017 at 12:59

Roady said:
#procommuting xD

Is that a motor below your bottle cage?

Roady · 30 Nov 2017 at 13:00

~~Yes.~~ No.

Lethal` · 30 Nov 2017 at 13:01

What actually is it?

I notice you cropped the thumb out for the forum version too

merlin · 30 Nov 2017 at 13:52

Bear said:
The people at 4iii are a bit smarter, they have an app that you can set an offset for leg imbalance if you know what it is to begin with.

Merlin seems to be able to get a good hour riding on track so he could do a proper FTP on track

I actually did do an endurance run a while back - one hour no drafting:

https://www.strava.com/activities/1283716967

No PWM there though - it's just Strava's mickey mouse power figures.

I can do the exact same again with 4iiii fitted with little trouble - I can access the track any time, it's lit at night too which is handy.

Bear · 30 Nov 2017 at 14:02

merlin said:
I actually did do an endurance run a while back - one hour no drafting:

https://www.strava.com/activities/1283716967

No PWM there though - it's just Strava's mickey mouse power figures.

I can do the exact same again with 4iiii fitted with little trouble - I can access the track any time, it's lit at night too which is handy.

Nice, wish I had something like that close by. There was talk of a sports village with velodrome getting planning in Aylesbury but not sure it's going anywhere

merlin · 30 Nov 2017 at 14:11

Bear said:
Nice, wish I had something like that close by. There was talk of a sports village with velodrome getting planning in Aylesbury but not sure it's going anywhere

It's great having it nearby - also there's three evening roller sessions every week through the autumn and winter to keep people ship shape - my older daughter and I do a roller session on a Tuesday evening - they put the tunes on and there's minimum 7 or 8 riders on rollers/turbo's with coach instruction - just makes it a bit nicer & social, fun.......(almost!).

UTmaniac · 30 Nov 2017 at 14:13

Wiggle parcel arrived, paid for guaranteed next day delivery at ~2145 last night...
DHB thermal bib tights (feels weird wearing bibs and tights at that, but good fit)
DHB bib shorts
DHB Flashlight thermolite socks

Used DHBLOOKBOOK code for £10 off £60+ order.

Only thing I wondered in hindsight was if I could have used DHB code, British Cycling code and got Topcashback if I placed the order at ChainReaction with a £99+ basket... But too late this time!

Roady · 30 Nov 2017 at 15:34

Lethal` said:
What actually is it?

I notice you cropped the thumb out for the forum version too

Specialized S.W.A.T. box (Storage Water Air Tools). Just allows me to carry 2 tubes as I don't carry co2 (1 in my saddle bag). It's large enough to also squeeze some arm/knee warmers into if required.

merlin said:
I can access the track any time, it's lit at night too which is handy.

I had a look for the entrance yesterday when driving past on the A456 and totally failed to spot it before the pub. Is there actually a turning you can make out/turn into when travelling East, or only West? It's on the dual lane part but there's no central reservation is there?

UTmaniac said:
Only thing I wondered in hindsight was if I could have used DHB code, British Cycling code and got Topcashback if I placed the order at ChainReaction with a £99+ basket... But too late this time!

Topcashback on Wiggle every time! Currently 4% too! :cool:

merlin · 30 Nov 2017 at 16:06

Roady said:
I had a look for the entrance yesterday when driving past on the A456 and totally failed to spot it before the pub. Is there actually a turning you can make out/turn into when travelling East, or only West? It's on the dual lane part but there's no central reservation is there?

It's after the pub not before.

You can only access it going Kidderminster bound - if you miss it you have to do the full RB to RB loop again! It's an accident blackspot too - the club secretary got run over outside the entrance last year.

Roady · 30 Nov 2017 at 16:23

After the pub heading to Kiddi = West bound only

Brutal! Too right, damn busy roads there. I think there's a school or something from looking at the map, with the track there, a school and the pub further up it'd make sense to have an underpass as it's such a busy road.

Vonhelmet · 30 Nov 2017 at 18:52

Boo, I lost a rear light on the ride home. I hit a pothole and it flew off and got run over by a bus. Fortunately I had a second one on the go.

Any recommendations for a cheapish flashing rear light that’ll clip onto a saddle bag? Ta.

merlin · 30 Nov 2017 at 19:06

Blackburn Local 20 lumen on offer at Ribble.