Time Trial / Time Trialling / TT

Might want to pop a chain on.

Looks fast!

Wheel choice - can anyome advise which is supposedly faster on paper for TT's: Corima aero 16 spoke carbon front wheel or Corima 4 spoke carbon. I appreciate all very dated by modern terms.

Depends on the yaw and the tyre, but I'd say 16 spoke on a perfectly still day, otherwise 4 spoke (though I don't think they ever tested that well?)

don't think they ever tested that well?

They were never class leading, but you shouldn't forget that in practice either wheel will only cost you at most 1s per mile against the class leader. Between the two there's so little difference that it's better to pick the one which feels better.

(I'll never know why Boardman didn't use at least a rear disc but) contemporary 4 spokes were chosen over the 16 spoke deeps for the 1993 hour record

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I'll never know why Boardman didn't use at least a rear disc

Same reason as Obree used two trispokes - so that everybody could Monday-morning quarterback the decision for the next 30 years 🙂

Lush .....you can't beat a bit of nostaliga

Anyone know of a place doing cheap "mono" armrests? I've got Zipp Vuka carbon bars on my Mason and I've added extra nuts to the armrest bolts so they don't slip around. Prior to that I'd use zipties between the two. If I moved to a single piece of carbon that sits across the top, they've never rotate around the extensions. It would make travel easier as currently I have to undo all the pads to get the bike in the box.

Have you thought of gettting a strip of perspex and moulding yourself ? I remember doing this stuff in technical studies at school back in the 80's with a gentle heat source it is very maluable and a lot cheaper than carbon fibre and bucks the hipster look.

I had not. But I would think it might be a bit brittle across the two armrests, compared to carbon at least and especially once it's been drilled and countersunk. No actual idea, just an assumption.

Plenty of cheap tribars have plastic elbow cups. On the other hand, making your own carbon fibre ones isn't much harder than forming them from plastic.

gettting a strip of perspex

I'd go polycarbonate (e.g. Lexan) rather than acrylic (e.g. Perspex)

Making single plane curved stuff in carbon is pretty simple if you want to DIY it. Brown packing tape is an excellent release agent, and carbon cloth and epoxy resin are easy enough to source.

If you want advice on making a DIY oven for curing prepreg carbon cloth, let me know...

You guys must be thinking of someone else. Don't let my awesome wrenching ability lure you into the sense that I like making anything that I could just buy from someone better at it than me.

I'm struggling to even muster the effort to measure the bolt hole locations.

Looks like there used to be some on ebay

Also need to find some 25mm bolts for the existing Zipp pads.

Where's your sense of adventure? I made this carbon fibre seat:

by taking a mould of my bottom.

mould of my bottom

I see you. I knew there was another reason you might want to help with this. You just want your own hippy arse™ for some kind of sick recreation, no doubt.

Actually one of those seats could make a TCR much more comfortable. Do they fit on standard saddle rails?

Could do. Definitely could do...

£150 for a WattShop one
https://www.shopforwatts.co.uk/collections/all/products/anemoi-arm-rests

I'm sure I've seen others though.

£141-£300
https://www.revolverwheels.co.uk/shop/components-accessories/revolver-blackbird-mono-tribar-arm-rest/

Also, looking at the clamps, I reckon a mono-rest would let me swap the clamps to the inside of the extensions which would give my hands more space on the tops.

Going to speak to Simon at Hotta Designs to see what can be done.

First event of the new season done in LFGSS colours held on U41 Chippenham & District Whls. Lovely flat course but very cold start about 2 degrees. Towards the end of the field with 26:18 probably over geared on 56x15 avg 80 rpm. Focuses the mind to improve and get down to hard work. Next weekend double weekend of events in Brizol.

Aaaand its -somewhat- ready!

More on the bodged / hacked di2 here: Current Projects

In this current setup its for a 90km event with 2 climbs in it totalling 1000m hence gearing. 50/11 should be enough for the first 40k flat. Then for club TT's it'll be 1x anyway. Race tyres will be Vittoria corsa.

Abandoned the spacer/bridge creation as I needed a different position. I bought the angled extension spacers from a Kingswann on Timetriallingforum.

Very happy with the position, did a few 1-1.5h rides on the turbo spending vast majority on the extensions.

What is the make of frame as part of your build project?

Its a Vitus Chrono II
https://www.bikeradar.com/news/vitus-chrono-ii-first-look/

After faffing with pins, numbers and wonky race number I thought it was time to upgrade my skinsuit. Just ordered a no pinz outfit. Will update on performance after this weeks races on Saturday and Sunday in Brizol.