Racer Tech Thread
#1626
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I agree with you in general. Clear cut rules are clear cut rules, and what good are rules if they are not enforced. There may be logistical considerations, though, like they don't have a battery of scales to weigh hundreds of bikes, or enough gauges to measure setback in a reasonable amount of time. So why have the rule at all? Maybe it has to do with insurance, or compliance with UCI regulations. There's lots of fishy stuff going on at USAC.
For a RR, practically speaking, what are they going to do? They could weigh bikes from the winners, but at that point the staff is already stretched. And......it is not the world tour so even if bikes were weighed beforehand what if parts swaps happened? It gets silly quick.
Back to your point...why bother having the rule? The rule does keep some folks honest but in a way winds up penalizing the honest ones.
My my other beef is one that anyone who has done one of these things may have observed. For TTs we would like to think the jig is authoritative, but those things are often flimsy, and I've seen them set up on ground that is not level. Whether an official chooses to pass a bike can have a subjective component, which is ridiculous. The guy who tells you your saddle is level + or - 3 degrees the night before is not the one who looks at it the day of the competition.
The he amount of energy collectively wasted by amateurs in the 24h leading up to these events is absurd, but there is not much way around it unless they completely ditch enforcement (which I support).
#1628
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And posted that he did not read all my posts [on the subject is presumed]. I found his responses to mine things I agreed with, as yours. I don't know what side anyone is on. I'm not questioning his - or your knowledge of stuff.
Yes you are correct, I would generally have a rider go with what feels faster over what is faster, because for a given rider, the mind trumps the physics - within reason. I acknowledge that. But there are many things that test faster in the lab/track that are not on the road. The simplest example I gave - a front disc on a 19mm 160 psi tire.
Yes you are correct, I would generally have a rider go with what feels faster over what is faster, because for a given rider, the mind trumps the physics - within reason. I acknowledge that. But there are many things that test faster in the lab/track that are not on the road. The simplest example I gave - a front disc on a 19mm 160 psi tire.
#1629
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I switched to 11 speed on my road bike recently. I just went to put an 11s cassette on my trainer wheel and discovered that the freehub won't take an 11s cassette.
The wheel is only ever used on the trainer. Should I:
- Pull a cog off the 11s cassette, which will definitely work
or
- Leave the 10s cassette on there and hope for the best
? In either case I will need to be careful not to shift off the end of the cassette while on the trainer.
The wheel is only ever used on the trainer. Should I:
- Pull a cog off the 11s cassette, which will definitely work
or
- Leave the 10s cassette on there and hope for the best
? In either case I will need to be careful not to shift off the end of the cassette while on the trainer.
#1633
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I switched to 11 speed on my road bike recently. I just went to put an 11s cassette on my trainer wheel and discovered that the freehub won't take an 11s cassette.
The wheel is only ever used on the trainer. Should I:
- Pull a cog off the 11s cassette, which will definitely work
or
- Leave the 10s cassette on there and hope for the best
? In either case I will need to be careful not to shift off the end of the cassette while on the trainer.
The wheel is only ever used on the trainer. Should I:
- Pull a cog off the 11s cassette, which will definitely work
or
- Leave the 10s cassette on there and hope for the best
? In either case I will need to be careful not to shift off the end of the cassette while on the trainer.
I would go with the 11 speed spacing. 10speed, as you know will work, but there is a slight difference in spacing and alignment and therefore wear. Just remember to adjust the limit screws.
#1635
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I switched to 11 speed on my road bike recently. I just went to put an 11s cassette on my trainer wheel and discovered that the freehub won't take an 11s cassette.
The wheel is only ever used on the trainer. Should I:
- Pull a cog off the 11s cassette, which will definitely work
or
- Leave the 10s cassette on there and hope for the best
? In either case I will need to be careful not to shift off the end of the cassette while on the trainer.
The wheel is only ever used on the trainer. Should I:
- Pull a cog off the 11s cassette, which will definitely work
or
- Leave the 10s cassette on there and hope for the best
? In either case I will need to be careful not to shift off the end of the cassette while on the trainer.
#1636
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#1637
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Yes this is pro, but related to the discussion a few pages back:
Changing bike/stuff. Getting more common.
Also how it is done. Give your preferred equipment to a teammate and swap.
"The race leader stopped to take a wheel from Ivan Basso on the first descent from Aprica"
Contador -"The changes depend on how the stage unfolds. We can use different type of tubulars, bearings or even stiffer wheels. These are solutions that over 30-40km can give a slight advantage. "
https://www.cyclingnews.com/news/uci-checks-bikes-of-contador-hesjedal-and-gilbert-for-motors-at-giro-ditalia
Changing bike/stuff. Getting more common.
Also how it is done. Give your preferred equipment to a teammate and swap.
"The race leader stopped to take a wheel from Ivan Basso on the first descent from Aprica"
Contador -"The changes depend on how the stage unfolds. We can use different type of tubulars, bearings or even stiffer wheels. These are solutions that over 30-40km can give a slight advantage. "
https://www.cyclingnews.com/news/uci-checks-bikes-of-contador-hesjedal-and-gilbert-for-motors-at-giro-ditalia
#1638
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Maybe this has been discussed but I'm only on page 10 of this behemoth. Can you run a 53/34 chain ring with di2, preferably with an 11-28? I've heard that the reasons not to do this with mechanical groups is shifting quality tends to suck, but can di2 account fix that? Thanks.
#1641
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Maybe this has been discussed but I'm only on page 10 of this behemoth. Can you run a 53/34 chain ring with di2, preferably with an 11-28? I've heard that the reasons not to do this with mechanical groups is shifting quality tends to suck, but can di2 account fix that? Thanks.
On an 11 speed Shimano crankset, with the proprietary BCD, I expect that would more or less work. It would be a major clunk from one chainring to the other but the di2 FD will definitely push that chain over to where it needs to be.
If not on 11 speed Shimano, I think it would be a mess. A 53T chainring on 110 BCD will be too flexy for the electric FD.
... also the RD will need a lot of capacity, I'm not sure the di2 RD has enough, that is probably the more critical issue.
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Caveat: my opinion. The biggest chainring you can run on a 9000 crank set up for 110 BCD with spacers is 52t. 52/34 is a big jump even for Di2. There is a reason they offer a mid compact. 52/36 is very close to what you are asking for and is a standard offering.
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A couple of tech questions for a guy returning to the road scene after a long layoff.
1) DA 7800 or 7900 chainrings: Do they work on any normal 130mm BCD spider? I use Cannondale Hollowgram cranks on all my bikes, have another set ready to go for this one, and want to confirm compatibility before I purchase.
2) Rim width: 23mm? 25mm? 27mm?
3) Rim depth: 38mm? 40mm? 50mm? 60mm?
4) Tire width: 23mm? 25mm? 28mm?
I'll be riding and racing on the road whenever I'm not racing my MTB. I live in VA during the school year, travel out west to CO during the summers. 65kg and I go up hills pretty well.
1) DA 7800 or 7900 chainrings: Do they work on any normal 130mm BCD spider? I use Cannondale Hollowgram cranks on all my bikes, have another set ready to go for this one, and want to confirm compatibility before I purchase.
2) Rim width: 23mm? 25mm? 27mm?
3) Rim depth: 38mm? 40mm? 50mm? 60mm?
4) Tire width: 23mm? 25mm? 28mm?
I'll be riding and racing on the road whenever I'm not racing my MTB. I live in VA during the school year, travel out west to CO during the summers. 65kg and I go up hills pretty well.
#1645
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Maybe this has been discussed but I'm only on page 10 of this behemoth. Can you run a 53/34 chain ring with di2, preferably with an 11-28? I've heard that the reasons not to do this with mechanical groups is shifting quality tends to suck, but can di2 account fix that? Thanks.
you'll get not-so-great shifting due to mismatched rings (/timing/shift ramps), but beyond that the cage just isn't set up to efficiently handle a 19T drop. if you set it up (vertically) for the 53, then the bottom of the parallelogram is likely to rub in at least some gears.
Shimano is usually conservative with capacity and wrap, at least for RDs (part of that is that one's hanger geometry impacts the max cog size), but my experience is that the FDs are spec'ed properly.
MTB FDs handle greater capacity, but that doesn't help you.
and di2, while great, has nothing to do with physical limits of the FD.
#1646
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A couple of tech questions for a guy returning to the road scene after a long layoff.
1) DA 7800 or 7900 chainrings: Do they work on any normal 130mm BCD spider? I use Cannondale Hollowgram cranks on all my bikes, have another set ready to go for this one, and want to confirm compatibility before I purchase.
1) DA 7800 or 7900 chainrings: Do they work on any normal 130mm BCD spider? I use Cannondale Hollowgram cranks on all my bikes, have another set ready to go for this one, and want to confirm compatibility before I purchase.
7900 rings are fantastic. noticeably stiffer if you take time to do a comparison (few people do). no, not stiffer in terms of power transfer, but stiffer when front shifting under load. that is where we experience flex.
yep...racing....i think you want something 404-esque. you descend what you climb. not sure what your power is like but as a racer even if you're in a pure HC it's not until at least 5% that weight is a thing--and quite possibly 6, 7% or more if you are strong.
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2) Rim width: 23mm? 25mm? 27mm?
3) Rim depth: 38mm? 40mm? 50mm? 60mm?
4) Tire width: 23mm? 25mm? 28mm?
I'll be riding and racing on the road whenever I'm not racing my MTB. I live in VA during the school year, travel out west to CO during the summers. 65kg and I go up hills pretty well.
3) Rim depth: 38mm? 40mm? 50mm? 60mm?
4) Tire width: 23mm? 25mm? 28mm?
I'll be riding and racing on the road whenever I'm not racing my MTB. I live in VA during the school year, travel out west to CO during the summers. 65kg and I go up hills pretty well.
#1648
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Are you ok with adjusting brakes when swapping wheels? My stable:
Training clincher: 56mm depth 27mm wide rim
Race tubular: 80mm rear 56mm front depth 27mm wide rim
Light race tubular: 38mm depth 25mm wide rim
No adjustment necessary. 25mm tires on all three. Fast with a great ride.
Training clincher: 56mm depth 27mm wide rim
Race tubular: 80mm rear 56mm front depth 27mm wide rim
Light race tubular: 38mm depth 25mm wide rim
No adjustment necessary. 25mm tires on all three. Fast with a great ride.
#1649
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That is a good point. Mixing different brake track width is a pain. It also changes the angle of the angle of the wear on the brakes.