Time Trial / Time Trialling / TT

For anyone who uses a proper tt wheel front and a disc cover wheel rear do you notice any peculiarities in handling?
I’ve used 4,5 spoke and deep front with a shallow rim rear on the track before, and had no issues, but never on road.
Am I overthinking it

I don't. But I'm a heavyweight meathead.
The bikes either goes where I want or it doesn't and I slow down or I crash.

Am I overthinking it

Yes. But if you want to really overthink it, a disc rear moves the centre of pressure back, so a crosswind turns the bike into the wind to counter the force pushing it sideways. This is also why the fin on an aeroplane is at the back 🙂 For my money, if it's too windy for the disc, it's too windy to ride at all.

Front wheels with odd spoke counts (mostly three) can create an oscillating turning moment about the steering axis as the wheel centre of pressure alternately shifts fore and aft of the axis. This bothers some people more than others, and the factors are not fully clear; rider weight, fork design and the rider position seem to be relevant, the latter including weight distribution and effective tiller length. I've used a HED3 for over a decade in all conditions, but I'm a fat bastard who sits a long way behind the BB with my elbows close to the steerer axis. It's kind of moot if you're halfway serious as there are plenty of wire spoked wheels now which outperform the HED3 in any conditions.

For wire spoked deep fronts, the problem facing the designer is that the fork offset is trying to put the wheel centre of pressure in front of the steering axis, causing the bike to steer the wrong way to counter the side force. This seems to have been bigger problem in the past when rims were v-shaped, probably because the front half of the wheel generated a lot of lift which added to the side load and the rear half didn't do anywhere near enough to counter it because it stalled at a very low yaw angle.

TL;DR: get out and ride, if you don't like the handling try something different

Spam - got some fixed TT / Hillclimb stuff for sale.

Road bike 10mi record falls again...

https://www.cyclingtimetrials.org.uk/race-report/25163#anchor

Considering the wind, that's mental.
Good to see UoN continuing to produce niche sporting talent!

Amazing effort. Be good to see what he can do on a course without a gift hill

Looks like formerly of this parish (and reportedly still lurking 👀) user 'eyebrows' won the Farnham RC open 25 at the weekend.

Is this bike CTT legal? I assume so, but I’m surprised.

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The stoker's handlebar looks interesting 🍆😳

Technically probably not, but I think the wording in the regs is pretty open to interpretation. Remember Nik Bowdler's bike from the Nat 12hr?

Out of curiosity, what is the mixed tandem record? :)

"We finished with an inconclusive result on the day, but it's now official. We beat the old record by a mere 0.85 miles. 465.77 miles in 24hrs. A new national record in the worst weather conditions"

465.77 miles in 24hrs

Given that tandems are faster than solos at short distances, I wonder if mixed tandem long distance always involves some kind of marital tiff?

I've never been in a relationship I'd want to risk in this way!

Haha if my missus hasn't left me already I don't think a tandem will make a difference. She's a massive sook on the flat though and doesn't want to ride tandem anyway. It would be a nice reintroduction to 24hr racing to do one tandem though :)

I'm more interested in touring on grav grav these days though.

Twice as likely to need time off the bike?

Wherever your relationship is heading, you'll get there faster on a tandem...

Considering some of the solo rigs out weekly…
@umop3pisdn cheers, was a windy day that day- not the most fun I’ve ever had.

Technically probably not, but I think the wording in the regs is pretty open to interpretation.

The interpretation seems to be that you can put fairings in front of the cycle parts to your heart's desire, but anything shielding any part of the rider is going to be trouble.

Modern shaped extensions that shield the forearms seem fine though?

I never noticed his elbow-length stocking gloves until now. :D

Modern shaped extensions that shield the forearms seem fine though?

They banned single fairings covering both arms. On any safety bicycle, the handlebar partially shields the rider, a rigorous regulation would define the maximum extent of this. Since Nik was riding before everybody went praying mantis, his bar would fall within any reasonable limitation

I wasn't pointing out Nik's wing but most people spending money on bars these days have sculpted extensions which would break your rule (of thumb). If I had a set maybe I'd have made up that 800 yards in the 12hr...

I wasn't pointing out Nik's wing

No, I was simply pointing out that despite all the fuss back then, most of the fast people now are more shielded than Nik ever was. You can't have zero shielding, because even a flat MTB bar blocks the rider to an extent of about 50cm²

That's the age old argument though - is it necessary or is it fairing? The new bars are clearly fairings but if CTT are happy to allow them, then I'll run one. Who's going to be the first person to make huge wings from their 2 aerobars that deflect out the sides as well as simply covering the arms? Arms Race.. geddit?

Who's going to be the first person to make huge wings from their 2 aerobars that deflect out the sides

Wasn't it @xavierdisley ? 😁

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I thought about those when I wrote it :)

If I get back to TTs the next obvious 'kit thing' to have a crack at is the cockpit and specifically the extensions. I just can't be arsed with testing these days though so I think I'll just stick to permanent semi-retirement and leave the Shiv on the wall.