The Dentist's Chair - Cervelo S2 Di2

So if you started at the height you finished, it was an average of 7.5% grade?

Well, at least it'll get dirty. And wear out. Please God let it wear out.

This build needs a redder stem!

You climbed 26,000 feet in 133 miles? Were you on a turbo trainer inside a passenger plane or something?

Nope, cycling in the Dolomites. That was the first three days.

well atleast you kept all your ugly bit, on one bike

haha nursery evaders are certainly upping their game recently

Hahaha amazing! Dan this deserves nicer looking chain rings :-(

I'm inclined to agree, now that the bike's finished (for now) and I can see it other than on a bike stand. I'll probably get some Praxis rings unless anyone's got any better suggestions for black compact 50/34t chainrings. The existing ones really are a bit too shiny.

That's at the top of the Tres Cimes de Lavaredo climb on the last day of my holiday in the Dolomites. The Chair worked perfectly (after a bit of Ui2 fine tuning) apart from the front derailleur which stopped working entirely one day. However, it turned out that this was the result of the connector to the front shifter having come loose, so it was an easy fix. Other than that (and a broken wire in transit on the way out) it worked very well, apart from an odd clicking noise from the rear wheel which I'm going to have to investigate.

It's not quite as stiff as I'd anticipated, although I think that's more the wheels than the frame. It's certainly fast in a straight line, but I did have a few interesting moments at speeds in cross winds due to the Zipps. Maybe I need some lower profile wheels for the mountains. Maybe some 202s would do the job rather nicely...

Did you have another rider on lower profile rims to compare the descent with?

We ran down Trollstigen at a fair rate and the gusts made life quite exciting- SF on low profile alloy rims was being blown around about the same amount as TW2 and I on 50-60mm carbon.

I felt it on my body though, which is easy enough to live with. Much like having a deep rear rim.

My 48mm carbon front rim tended to auto-steer a touch. The theory is that the center of pressure from the side wind is infront of the steering axis on a standard deep V shape. So it turns the front. Whereas the center of pressure is pulled back on a firecrest.

Good point, I'm now trying to remember how it felt- from unreliable memory it did feel as though I was being pushed around as a whole, rather than the front wheel being tugged hither and yon.

There were a couple of riders on low profile alloy rims who were descending at a similar rate, and another rider on deep section rims (Mavic Cosmics). The chaps on low profile rims seems to be knocked about rather less, although of course it's hard to compare without actually riding the other bikes. I think it may just be a question of getting used to the new bike and wheels.

One problem I did have occasionally was getting into a sort of feedback loop where the bike would be knocked sideways, I'd steer to correct (and, I suspect, over-correct) and then the bike would be blown sideways again. It felt similar to the front-end shimmy you sometimes get at speedy on bikes with noodley frames, but subtly different.

I think I just need more time to get used to it really. Either way, it didn't stop me from descending quickly and enjoying it.

I want me a Cervelo.

Now that Spring has sprung, and the winter bike has been put away (for now), I've made a few changes to the Chair so it'll be ready for 2014. This is what it looked like when it got put away for the winter:

I picked up a pair of Zipp 808s cheap(ish - all things are relative) and so I thought I'd try the rear one on the Chair. The front one doesn't have a tyre glued onto it, so that wasn't an option. The rear has a SRAM XG-1090 12-25 cassette fitted - a thing of great beauty, and ridiculously light at only 149g.

The other major change was a change of bottom bracket and crankset - Rotor 3D+ cranks with a Power2Max power meter spider added.

The Power2Max power meter seems pretty good so far - it paired easily with the head unit, the numbers are credible and consistent. I might try and run the Chair with a Powertap rear hub to see how the numbers compare from the two systems.

The Chair did manage to disgrace itself on the club run on Sunday, as the clinch nut which provides the preload for the bearings in the rear hub came loose (user error - the rear wheel came with a Campag freehub and I changed it for a Shimano one, and must have forgotten to do it up properly) and it had to be tightened up mid-ride. But the rear wheel does make a lovely wub-wub-wub noise, so all is forgiven. I suspect it'll mostly be used on my time trial bike though.

New cranks look around 4 million times better.

I'm a fan of large rear/shallow front, there's something not quite working in the decals though I think, but as you point out the noise over rules that.

Saddle still belongs in the bin, preferably in a plain wrapper.

Saddle still belongs in the bin, preferably in a plain wrapper.

The same "discrete packing" it arrived in, probably.

I quite liked the original cranks, and I'd bought some Praxis black chainrings to go with them. But the S2 deserves a power meter, so they had to go. I'm glad I could get some Rotor cranks with the old, and relatively understated, graphics though. The fact they were only 200 quid was nice too. Still not a fan of the current 80s-computer-game Rotor graphics.

I agree the stickers on the Zipps don't really work together, but I think the Chair will usually run with 404s front and rear.

As for the saddle, my arse gets the casting vote on saddles and it likes Flite Flow saddles. That's why I currently have about, ooooo, a dozen of them. Mind you, I am experimenting with Fizik Ariones, after being surprised how comfortable the one on the BMC track bike I rode at the BMC velodrome in Grenchen was. If I decide that I do like them after all, the Chair might end up with one of these:

http://images.evanscycles.com/product_image/image/f02/284/efe/104260/product_page/fizik-arione-r3-bmc-racing-team-edition-saddle-bar-tape.jpg

Still too early to make that switch though. Especially as I've just bought another Flite Flow Kit Carbonio as a spare for that one...

Still not a fan of the current 80s-computer-game Rotor graphics.

The nicest graphics on the whole bike. I'd have the frame repainted RITTE 8-bit stylee to match.

A few changes to the front of the Chair recently. I have:

1. Removed a couple of spacers and chopped down the steerer tube a bit. I reckon with a few months' more stretching the final spacer can go.
   
2. Removed the expanding bung and replaced it with a steerer bung I made myself (a whole 4g) and glued into place with some JB Weld.
   
3. Replaced the Ritchey C260 stem with a Zipp Service Course SL
   
4. Replaced the Ritchey Superlogic bars with Zipp Vuka Sprints
   
5. Fitted a tester stem cap - 'Rule No. 5'
   
6. Replaced the K-edge Garmin mount with a Tillquist one.
   
   

Back on 404s all round, it now looks like this. 7.21kg, which is fine by me.

Where can I find this Tillquist mount? I use this zipp stem as well and it looks neat

bro do you even weightweenie?

Morten's now got a web shop here.

Morten's now got a web shop here.

Ordered now, 20% off as well ;) thanks!

I would like one for a 3T Arx LTD, but he doesn't seem to support those.

I totally missed Dammit's earlier call to this thread, congratulations on sharing my terrible taste in chains.

Is that chain still going?

Yep, still going strong. I try to avoid cleaning it.