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Old July 17th 19, 03:53 PM posted to rec.bicycles.tech
Tom Kunich[_5_]
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Default Electronic Shifting

On Tuesday, July 16, 2019 at 6:11:11 PM UTC-7, jbeattie wrote:
On Tuesday, July 16, 2019 at 12:41:39 PM UTC-7, Tom Kunich wrote:
On Monday, July 15, 2019 at 6:23:58 PM UTC-7, jbeattie wrote:
On Monday, July 15, 2019 at 4:16:33 PM UTC-7, Tom Kunich wrote:
On Monday, July 15, 2019 at 10:22:16 AM UTC-7, jbeattie wrote:
On Monday, July 15, 2019 at 7:14:19 AM UTC-7, Tom Kunich wrote:
On Sunday, July 14, 2019 at 5:04:19 PM UTC-7, jbeattie wrote:
On Sunday, July 14, 2019 at 4:13:09 PM UTC-7, Tom Kunich wrote:
On Sunday, July 14, 2019 at 12:53:36 PM UTC-7, jbeattie wrote:
On Sunday, July 14, 2019 at 8:59:31 AM UTC-7, Tom Kunich wrote:
On Sunday, July 14, 2019 at 1:44:40 AM UTC-7, Tom Evans wrote:
On 12/07/2019 22:01, Tom Kunich wrote:
On Friday, July 12, 2019 at 9:13:51 AM UTC-7, Tom Evans wrote:
On 10/07/2019 21:19, Tom Kunich wrote:

I am sure that electronic shifting will get more reliable. But again - is there any advantage to it? There can't be more than 20 grams weight advantage to the electronic stuff.

Long term it will probably be cheaper than mechanical.

It simplifies quite a few things. Simpler shifters, no gear cables, no
need for frame additions to route gear cables. The electronic components
will be dirt cheap.

What is the different between internal routing of wires (that come with the group) and cables? Since the ratcheting mechanism is in the rear derailleur instead of the shifters it would be a little cheaper to maintain I imagine.

My expectation for the future would be no wiring. Each component having
its own battery and the using wireless communication. Cheap and simple.


Yesterday in Stage 7 you could see some guy grab a handful of brakes because he was about to touch a wheel. The hydraulic disk locked up and top-ended and threw him right on his face. Pretty ugly and EXACTLY what I did on my cyclocross bike.

My disk brake newbie/cross bike newbie failure was to lose the back
wheel braking and cornering in the wet. For some reason I thought disk
brakes and 40mm tyres could change the laws of physics, unfortunately not.

They had the camera directly on one of the bikes in the Tour as he took a near miss and slammed on the disk. The effect was exactly the same that I had on my cyclocross bike coming down a steep off-road hill - The bike turned directly over the front wheel. On flat road that is one thing but going down that steep hill was another thing altogether since I must have fallen at least 10 feet and more likely 12. But that also gave me time to turn and land on my side. And the ground was soft enough not to break bones.

I've never gotten close to going OTB on my discs -- at least no closer than with well adjusted dual pivot rim brakes. Modern road discs usually have a 140mm (small) front rotor and front braking only modestly better than rim brakes in dry weather. Rear braking is considerably stronger, and you have to learn not to be ham-handed. I fish-tailed a few times getting the hang of my rear disc.

I was riding today with a couple of friends -- all of us were on CF and one had Di2. All of our bikes exploded at the same time, and the Di2 caused an electrical fire. One guy was riding discs, and he also went over his bars as his frame exploded. These modern bikes are super dangerous!

-- Jay Beattie.

Jay, that it can happen is incontrovertible. Not just my case. You don't have to believe me and most do not as if I could care. It happened to one of the most experienced riders in the world on TV during the Tour de France. On paved road and without him touching another bike.

As far as I could make out, he got an overlap and then the guy in front started coming over on him and he hit the brakes hard. Though perhaps this isn't pertinent to your situation since the disks used on these racers are the 206 mm and most normal road bikes used the smaller 150 or 140 mm and it would take a lot more hand pressure to lock those.

You can go OTB with dual pivots. And are you nuts, the pros are using 140mm/160mm front rotors -- not 206mm. That's tandem size.

-- Jay Beattie.

You better tell that to Bob Roll then who said that they were using 206's on the mountain stages.

You better get your ears cleaned. Just for context, this is a 203mm (not 206mm) rotor on this tandem. https://tinyurl.com/yy8y8w43 https://tinyurl.com/y3zkk4db

http://www.cyclingnews.com/features/...emsix-gallery/ 160mm rotors and many on 140mm rotors. Look at the footage and consider the effort mechanics would have to go through to adapt the calipers for 206mm rotors.

I have the 200 mm rotors on my CX bike and all I did was use the standard mounts. I have been trying to sell that bike or else I would convert it to smaller disks just by using the other set of mounting holes.

WTF? A 200mm front rotor on a CX bike? No wonder you're going over the bars. Why would you do that?

-- Jay Beattie.


Because at the time there wasn't anything smaller available. Road disks are a relatively new thing.


Hmm, in 2005, 160mm discs were OE on my Cannondale CX bike. I've never seen a CX bike with 200mm front rotors -- and these days, a lot of the CX bikes are going small with 140mm rotors. If you still have the bike, you should size down to 140s or 160s and see what you think.

-- Jay Beattie.


Why should I invest in something I'm trying to sell?
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