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• #52
my regular gear here in cornwall was 99", there is a course on the Lizard that has some very steep bits so dropped to 93, 94" or something, i chose a gear based on the time I wanted to do on a course.. so say I wanted to do a 21 or 22min '10' I'd need to average 27mph say, so I looked at a cadence of around 115 for that meaning I could go faster, up to say 140rpm on the bits that went down, and slower, say 85rpm on the up bits.. or slower out the saddle if it was steep.. which is how I settled on 99".. It did mean beasting it a bit but it seemed to work pretty well as a rule most of the time.
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• #53
I'm going to pop out and try the course with 52X14, if I can push it up the hill then it would be 140 rpm for 41mph down to the finish, which I reckon should be ok.
Size- I've got a position which seems to work on the 58cm Langster- but with a 60mm stem.
I think a 54cm might be the one to use, although I'd certainly have a seatpost like a broom stick at that point.
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• #54
heres mine (although i just sold the frame)
did you not just buy that frame? or was it an old thread revisited recently?
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• #55
thanks for that mdcc, that gives me something to think about and work on.
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• #56
I'm doing the same thing, currently pondering gearing for my (far, far too large) Langster framed TT bike.
The TT that I am going to do is the Bexley 10, which goes uphill for 4 miles and then downhill for 6, so you need a gear that you can push up the hill that you then don't spin out coming down.
This is something of a challenge- FixedWheelNut was running 97 gear inches, which he pushed up a hill that had me shift to the inner ring.
Inner rings, where fitted, should be kept sparkling clean and unused in order to show how well used the big ring is.
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• #57
I am aware of this
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• #58
i never tried time trialing, but as my dolan seta is not really in use i'm thinking of rebuilding it for a first fixed time trial test.
i have a 14t in the box so gear ratio would be 48/14.
syntace stratos 200 is already mounted, so i only need the aero bar.
i'm not sure if i should change the seatpost or the stem, will see how i sit on the bike with the aero bar.any further advice or typical first mistakes???
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• #59
don't lean
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• #60
Don't stop pedalling.
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• #61
Don't sleeveless
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• #62
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• #63
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• #64
heres mine (although i just sold the frame)
inverted photo with inverted tipo ?
WDF ? -
• #65
WDF ?
Shouldn't that be W le F?
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• #66
By the way, it's left hand drive; aren't all Continental bikes like that :-)
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• #67
PNut uses an old steel frame and he has gone <20:00 for 10 miles.
Et voila:
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• #68
That guy should get an aero helmet and shoe covers before even thinking about an aero frame.
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• #69
^My mate Pete uses neither and just got 8th in the National 10, oh, and he's a vet.... Heart and lungs beat marginal gains most of the time.
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• #70
Does he have those aero ear piercings though?
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• #71
Nah, his 'him' is aero, the little sod is so skinny there's nothing to hide behind when he's on the front in training.....
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• #72
^^^ Your mate Pete should also have an aero helmet and shoe covers before getting an aero frame. Marginal gains beat smaller marginal gains. Heart and lungs are irrelevant to this statement.
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• #73
......and aero helmets are irrelevent on anything other than a dragstrip!
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• #74
no.
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• #75
It's probably true that many people who haven't been to a wind tunnel or done extensive field testing are getting no more benefit from long-tailed helmets than they would get from shaving their heads
Most people use a small track frame for fixed TT use. As an example, I used a 53cm Koga FPT, while I'd have bought the 56cm for sprinting. I've now switched to a 51cm Cervelo T3 with 60mm of spacers under the tribars to get the base bar lower and create a space between the wing and the elbow cups
For a budget build, I'd keep an eye on classifieds (not just here) for an older steel (531 ideally) track bike or frame. The thin tubes are stiff enough for TT use (really, they were stiff enough for Olympic track sprinters back in the day) and since nothing under £2k has been designed to be actually aero rather than cosmetically aero, you might as well stick to keeping the A part of Cd.A down. PNut uses an old steel frame and he has gone <20:00 for 10 miles.
Since you don't yet know what position you're going to adopt, and it will change with practice and development anyway, you're going to have to take a bit of a punt on the sizing. "Stack & Reach" is the sizing model you need to think about, and of those you need to concentrate on reach, since this will affect the handling. Stack can be fixed with stem angle and risers under your tribars, but fixing reach with extreme stem lengths messes up weight distribution and tiller geometry.