Deep section wheels and mountains

markwb79

Anyone mix the two?

I am riding L'etape this year and would like to ride my Easton wheels, they are 58mm rims though.

A big no no, or ok to ride them? (assuming it isnt too windy?)

Cheers
Mark

hatone

58 mm is pushing it. I'd say 50 mm is the max I would ride in the mountains.

Having said that, when climbing rim depth isn't the real issue, but wheel weight. If your deep sections are light enough, then you'll be fine providing there is low'ish wind.

markwb79

Yes they are light enough, thats I want to ride them.

I was more worried about descending actually?

maddog 2

yeah, wind is the issue. I came off Fleet Moss the other day on 50mm RS80s and over 40mph they were proper scary - I had to brake!

Normal rims are much better in the hills IMO.

ugo.santalucia

If you are braking on carbon, leave them at home... last thing you want is having to worry on the descends instead of enjoying them... especially if it's wet.
If you have alu braking surface, well, then they're not that light, and you are better off with less profile.

Descents are full of idiots who can't descend and brake at the wrong time, best to have the edge

oldwelshman

ugo.santalucia wrote:

If you are braking on carbon, leave them at home... last thing you want is having to worry on the descends instead of enjoying them... especially if it's wet.
If you have alu braking surface, well, then they're not that light, and you are better off with less profile.

Descents are full of idiots who can't descend and brake at the wrong time, best to have the edge

+1.
No benefit going up hill and even worse going down!!
I went down MonteGrappa in italy and had no brakes half way down!! rims were scorching.Nothing to do with technioque just so many short fast switchbacks and no choice other than brake.
It was much better usin 35mm dura ace carbon laminates, better up and down.
Couldnt beat the deep section on the italian nice flat smooth roads tho :-)

markwb79

Whats wrong with braking on Carbon rims?

Barbarossa

Markwb79 wrote:

Whats wrong with braking on Carbon rims?

The carbon - or rather the epoxy that holds it together - is a poor conductor, so on long descents the wheels can overheat.

hatone

So why then do Pros for that matter still descend faster than all of us on carbon rims and don't have the over-heating issue? Better technique?

proto

Fair few on the Dragon Ride on sunday. I thought they were nuts. Mostly Cosmc Carbone clinchers, quite heavy and not much aero advantage grovelling uo Devil's Elbow and the Bwlch

benno68

proto wrote:

Fair few on the Dragon Ride on sunday. I thought they were nuts. Mostly Cosmc Carbone clinchers, quite heavy and not much aero advantage grovelling uo Devil's Elbow and the Bwlch

The deep section rims look good though, that's all that matter to some. I was on Ksyrium Elites, but that's cos I'm a fat boy - the more bombproof the better!

ugo.santalucia

hatone wrote:

So why then do Pros for that matter still descend faster than all of us on carbon rims and don't have the over-heating issue? Better technique?

Because they do have all the road for themselves and don't have to share it with cars coming up. When it is wet you see the difference between those who chose carbon and those who went for alloy... They can lose minutes

Rule74Please

hatone wrote:

So why then do Pros for that matter still descend faster than all of us on carbon rims and don't have the over-heating issue? Better technique?

a racing rule "brakes are for cowards"

Most pro's live and die by these words. that's why (and closed roads) they can descend like a stone.

PS it is good fun too but mass start sportif is not the place to practice descending on account of the morons who obey the above rule

slow_step

I've just got back from a weeks training in the Pyrenees and decided to take my carbon deep section tubs (38 at the front 58 at the back) . I have previously used Mavic R-sys wheels, which are great wheel but much prefer the feel of the deep sections.

I was a bit dubious at first as my head said take the Mavics but my heart the Miche Super types. Having pre-pared them with some stans tyre sealant I had a hassle free week with them. They appeared to climb better than the alu clinchers and were far better at descending. Will definitely be using them for the etape this year, the roads are closed for it !

That said a friend of mine did not have such good luck with carbon clinchers, the rims overheated in descending the Aubisque resulting with rims that warped so much they were not ride-able.

If your Easton's are tubs I'd be tempted to give them a go but put in some sealant first and take a spare tub with you

friso

Like a numpty i did last years Lakeland Loop on cheap full carbon 50mm clinchers and nearly died because of it

It was a very hot day and due to having carbon braking services the rims heated up so much that the air presure in the tyres increased with the heat and first exploded the front tyre off the rim coming down Hardnott and then exploded the rear tyre clean off coming off Wrynose

Both times when i tryed to fit new tubes i had to wait for the rims to cool down as they where too hot to touch. This year i used Kysrium SL's and being a bit nervous after what had happened the year previous i stopped at the bottom of Wrynose to check the rim temperatures by hand and they weren't even hot to touch

So i think it comes down to the quality of the wheels and how skilled a rider you are as i know i brake a lot more than a pro would adding more heat in to the rims

markwb79

slow_step wrote:

I've just got back from a weeks training in the Pyrenees and decided to take my carbon deep section tubs (38 at the front 58 at the back) . I have previously used Mavic R-sys wheels, which are great wheel but much prefer the feel of the deep sections.

I was a bit dubious at first as my head said take the Mavics but my heart the Miche Super types. Having pre-pared them with some stans tyre sealant I had a hassle free week with them. They appeared to climb better than the alu clinchers and were far better at descending. Will definitely be using them for the etape this year, the roads are closed for it !

That said a friend of mine did not have such good luck with carbon clinchers, the rims overheated in descending the Aubisque resulting with rims that warped so much they were not ride-able.

If your Easton's are tubs I'd be tempted to give them a go but put in some sealant first and take a spare tub with you

Indeed they are tubs, so there is a large weight advantage over my other wheels. Sounds like a similar dilemma to yours then!

I am contiplating taking two spare tubs for the etape, never thought of using sealant in before a puncture though?

mamba80

I ve used Carbon tubs (Conti comps) for the Maratona and for a few UK sportives and take a Pre used Vitt cx for a spare and a tin of Pit Stop and touch wood never had to use either, road surfaces tend to be better, less likely to pinch flat and as the tube isnt in direct contact with the rim, there shouldnt be any issues with heat.
Using Shimano carbon pads, the braking is far more powerful in the dry and better in the wet and with far less pad wear.

I would use the Pit stop first and then the tub if you do flat. chuckin in a load of sealant first seems pointless, you ll soon be up to the weight of Clinchers - with no garantee it will work.

hatone

Talking of braking power on carbon rims, I've noticed cork pads brake even more sharply and dissipate heat better than conventional carbon pads.

Has anyone experienced this?

itsnotarace

Yes I use Corima cork pads and am very happy with their performance. They give a very modular feel, I tried a number of other carbon specific compounds and found they either left nasty residue on the brake track or were really grabby.

BeaconJon

Interesting topic. I've just built up an FM028 with 50mm full carbon clinchers and will be taking it to the Alps to watch the Tour. Thing is I'm a bit nervous about using the carbon rims as I will be doing a few miles including descents of the Galibiere, Colombiere, Grand Colombiere and the Joux Plan.

Last year on another bike I ride my Zondas in both wet and dry conditions and didn't have any issues. I'm tempted to play it safe, put the 11 speed cassette on the Zondas and change the pads.

Tom Butcher

I think it's one of those that if you are a confident descender and it's dry (and you are confident it will stay dry) you might be OK - I know people who have used them for the Marmotte and said they didn't see the problem - personally I wouldn't.

As for the pros - in the wet it's pretty common even for them to swop in aluminium wheels or an aluminium front for the mountains.