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yup, the Gazelle was specced that way, and the cannondale must have been used to TT, prior to it being Adoubltap's: brake holes front and rear.
its kind of weird, I'm sitting in a premier inn right now, posting about stuff as if it were near to me, but in actuality its not.
i can't wait for these interviews to be over. -
y
its kind of weird, I'm sitting in a premier inn right now, posting about stuff as if it were near to me, but in actuality its not.
i can't wait for these interviews to be over.?
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The most shocking thing about this information is that I might actually understand what all the numbers mean. I think I might have to side with Max now. Moar pics!!
Last time I got involved in this discussion, I actually got my hands dirty and applied a digital vernier calliper to Campag C-Record and Shimano UN-73 spindles. They were exactly the same size across the flats at the narrow end. Just to check, I've measured a Campag Victory and a cheap FSA JIS unit that happen to be on the floor beside me, and again the dimensions are the same:
Across flats at narrow end: 12.68 to 12.71 Campag, 12.67 to 12.72 FSA
Across flats 13.5mm inboard of narrow end: 13.57 to 13.62 Campag, 13.56 to 13.62 FSA
In neither case are the "square" tapers truly square, based on 8 separate measurements on each spindle. On this n=1 sampling, we might say that Campag get closer to 1/2" more of the time.The only remarkable difference between them is that the Campag has a 45deg x 1mm chamfer on the spindle ends, so on a "110mm" spindle the effective length, i.e. the full width from the start of the 2deg tapers, is only 108mm.
The slope of a 2deg taper is 1:28, so the 0.05mm difference between largest and smallest measurements could make a difference of 1.4mm in chain line, i.e. +0.6 or -0.8, which would double if the crank bores are as variable as the spindles.
Somebody else on the same discussion on WW had taken a selection of Campag and Shimano DA cranks and measured the taper bores in the cranks:
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For Herne Hill only = DA 7600 36H/CXP33/Phil cog Diamante Prolights and some sensuous green latex inner tubes....
Nice; those Diamante ProLights roll really well for a cheap tyre. My brother and his wife have just upgraded to them on their track bikes. Of course, 36 spokes flailing away in the breeze are going to kill any speed you've gained with the tyres...
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The Pro Lights make/the whole bike makes a great noise when they are inflated to 160 psi.
The tyres might be rated for that, but the rims certainly aren't, maximum 9.5bar for a 23mm tyre. I don't suppose the extra 1.5bar is going to kill them, especially if you don't wear the rims down by using them as brake discs, just saying.
They invite p_nct_r_s on the road, but in this case that's a non-issue.
I've got the even lighter Ultra Speed on my TT bike at the moment (same casing, even thinner tread), so you're erring on the side of caution as far as I'm concerned :-)
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Nice; those Diamante ProLights roll really well for a cheap tyre. My brother and his wife have just upgraded to them on their track bikes. Of course, 36 spokes flailing away in the breeze are going to kill any speed you've gained with the tyres...
Luckily have CX Rays on my Cane Creek Volos tubs with (according to WW sources) the best buy Schwalbe Milano tubs.
edit by strange coincidence I was just looking at the Vittoria Japan website and saw those Ultra Speeds listed as their "Track clincher" tyre. Never herd of them before but S-Deals seem to have some 23c.
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The tyres might be rated for that, but the rims certainly aren't, maximum 9.5bar for a 23mm tyre. I don't suppose the extra 1.5bar is going to kill them, especially if you don't wear the rims down by using them as brake discs, just saying.
I've got the even lighter Ultra Speed on my TT bike at the moment (same casing, even thinner tread), so you're erring on the side of caution as far as I'm concerned :-)
They came on some Mavic Ksyrium Elite's and some basic Alex rims.
I think they say they have a minimum PSI of either 120 or 140 (memory fail), which I doubt the Alex rims are rated to- and would hope the Ksyriums are, but I don't know that either!
I now run them on CXP30's for the track- and (you guessed it) I've no idea if those rims can take 160psi either...
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Re: Vittoria Ultra Speed
They are not in the 2010 Vittoria catalogue (I don't think they were even in the 2009 range), so any that are still around will have been on the shelf since before they were discontinued in the aftermarket, although they are listed as the stock tyre on the 2010 Felt TK2 so Vittoria must still be making them for OEMs.
For a budget track tubular, I'd take the Vittoria Pista CS, which is only £5-£10 more than the Milano. Schwalbe make great touring tyres, but I wouldn't touch their "racing tyres" with a 10 foot pole, they are notoriously slow rolling.
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I now run them on CXP30's for the track- and (you guessed it) I've no idea if those rims can take 160psi either...
9.5bar maximum for a 23mm tyre is straight from the Mavic Tech manual, and applies to all Mavic road clincher rims and wheels.
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Just a few small changes to my Mercian. Decided to put some Cinelli Criterium drops on it - I'm hoping to take it round the track come March, and want to get used to riding it with drops.
Also changed the Rolls for an Arione, which IMO doesn't look as good, but is much comfier on longer trips.
Also got a new Cinelli stem, though you can't really tell from the (crap) pic.
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So without recourse to the calculator- approx 140psi?
How about the Ksyriums? (Playing chess and too lazy to Google) I presume they come under the same thing?
In which case it seems odd that they came with those tyres.
Yes, 9.5bar=140psi, near enough given the resolution and accuracy of pump gauges.
The 120psi "minimum" written on the sidewall should be taken with a large pinch of salt, usually that number refers to the lowest pressure which will safely support the maximum design load, which would be relevant to you only if you weight 20st. The maximum written on the sidewall is again only about the tyre, and you should always check the rim rating too and use the lower figure. Corima carbon clinchers, for example, have a maximum of 8bar for 23mm tyres. Stress on the rim increases with increased tyre cross section, as the casing tension rises as a function of curvature radius.
http://hyperphysics.phy-astr.gsu.edu/Hbase/ptens.html#lap2
MaxC
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the return of another flouncer?