Bicycle Tech/Gear Discussion Thread

Oct 28, 2013 at 02:25 PM

@David

The 4-axis stem is solid and works well. The c260 seems nifty, but you have to remove the bar tape and lever to install it. Ask Ryan about his. Go with the 4-axis. You won't regret it

Jules

Oct 28, 2013 at 09:44 PM

@Wump I forgot to ask; some guy had a bizarre Polar contraption on his bike at the Donut Derby; looked like a long (large) device attached to his chain stay, with two wires coming out - one of which went to the Jockey Wheel of his rear derailleur.

What the hell is it?

Didn't get a photo, but thought the walking Encyclopedia of Bike Tech might know...

Craig Zolan

Oct 28, 2013 at 09:52 PM

Did it look like this:

This was Polar's first attempt at a power meter but it wasn't direct force measurement. It used chain speed and chain tension to calculate power. More info here:
http://www.bikeradar.com/us/gear/category/accessories/gadgets/cycle-computers/product/review-polar-cs600-cycling-computer-with-power-output-sensor-17033/

dstokes

Oct 28, 2013 at 10:04 PM

Here is the equation governing the vibration:

Where f_l is the frequency of vibration (substitute 'chain' for 'string')

If the system is calibrated, you can calculate power from the tension on the chain (directly related to force you are applying to the pedal produces tension on the chain) and the speed that you are moving.

Jules

Oct 28, 2013 at 10:32 PM

Wow. Yup, that was it.

mattie davitt

Oct 28, 2013 at 11:39 PM

It was a turd. All you need to know.

Wes Tillman

Oct 29, 2013 at 01:27 AM

I need some fall / winter tires... Should I go with gatorskins or grand prix 4 seasons?

Jules

Oct 29, 2013 at 01:54 AM

Wes Tillman said:

I need some fall / winter tires... Should I go with gatorskins or grand prix 4 seasons?

Gatorskins

Jeff Owens

Oct 29, 2013 at 02:25 AM

Jules said:

Wes Tillman said:

I need some fall / winter tires... Should I go with gatorskins or grand prix 4 seasons?

Gatorskins

4 seasons: more expensive and not as durable, but better cornering and wet conditions and more comfy. And lighter (?).

But when it's super nasty, you're probably not going much over 80 miles in cold and rainy conditions, so it's hard to argue against the gators. I liked the Vittoria Rubinos last year as far as comfort and cornering (and much cheaper than both the seasons and gators), but not quite as durable. Changing a flat when it's 36 degrees and raining sucks. Yet I bought a pair of 4 seasons again this year b/c I have a taint crushing aluminum bike. 25c Gatorskins at a lower pressure and you'll be fine.

Jules

Oct 29, 2013 at 02:29 AM

For what it's worth: away back when I posed about a shifter that would shift to the 11... I took it to Murray at RB and he sorted me out; cable was frayed up by the metal ball. Replace cable, all is good. Rode like silk at bubble; there's the pity of it I suppose.

mugwump

Oct 29, 2013 at 02:37 AM

Craig Zolan said:

Did it look like this:
This was Polar's first attempt at a power meter but it wasn't direct force measurement. It used chain speed and chain tension to calculate power. More info here:
http://www.bikeradar.com/us/gear/category/accessories/gadgets/cycle-computers/product/review-polar-cs600-cycling-computer-with-power-output-sensor-17033/

Mattie had it right. A turd. I tested one out. If you measured your chain wrong, either the length or the weight,it was useless.

Brendan Rigby

Oct 29, 2013 at 10:20 AM

Tires: I've been riding 4Seasons since March or so and find them quite nice. I have suffered sidewall tears at a higher rate than previous tires (one sliced en route to Floyd, another frayed). Seems that the sidewalls fail before the tread runs out.

Haven't tried Gatorskins. Haven't gotten enough flats running these 4seasons to make me switch.

Erika Tarte

Oct 29, 2013 at 02:32 PM

Am I alone in having the worst experience with Gatorskins and pinch flats? As soon as I switched from Conti Grand Prix over to Gatorskins on my clunky commuter DT Axis 2.0s, I started averaging 2 pinch flats a week regardless of tire pressure.

Jules

Oct 29, 2013 at 03:42 PM

@Erika wow. That's a lot of pinch flats! I've never punctured a gatorskin but I did just recently pinch flat one on a low pressure trying to ride some stairs.

That definitely sounds very fishy.

neilx

Oct 29, 2013 at 03:58 PM

For winter, I like Maxxis Re-fuse 25s. The ride is a little stiff, weight isn't bad, they're generally less expensive than the Contis etc. and I haven't flatted one yet (fingers crossed).

Brendan Rigby

Oct 29, 2013 at 04:06 PM

Erika Tarte said:

Am I alone in having the worst experience with Gatorskins and pinch flats? As soon as I switched from Conti Grand Prix over to Gatorskins on my clunky commuter DT Axis 2.0s, I started averaging 2 pinch flats a week regardless of tire pressure.

when i first read this i didn't see you said per week. that's too many pinch flats; something is wrong. maybe it's the tire, but maybe it's your rim or tube or a combination of all of the above. are you riding over a bunch of actual gators? someone with more experience will likely have some insight.

Erika Tarte

Oct 29, 2013 at 04:30 PM

Rolled over only 1 actual gator (maybe just a particularly scaly rat?) but otherwise just my normal commute and PP laps. Didn't see anything on either of my rims (yep, both front and rear pinch flats) and only ever flatted once — in a construction zone — in the 9 months I rode the Contis. I actually switched wheels and tires after about the 6th or 7th flat and haven't had a problem. FWIW, the Gatorskins were hell to get on, so I fully acknowledge there may have been tube/bead issues, but I was always fairly diligent about checking for that...

dstokes

Oct 29, 2013 at 04:42 PM

Erika Tarte said:

Am I alone in having the worst experience with Gatorskins and pinch flats? As soon as I switched from Conti Grand Prix over to Gatorskins on my clunky commuter DT Axis 2.0s, I started averaging 2 pinch flats a week regardless of tire pressure.

I once had a similar experience with a particular tire/rim combination where I was having pinch flats every day! This is a long and wonderful story that I won't get started with. But the take home message is that certain tire/rim combinations just don't work. The fact that you solved your problem by swapping rims/tires is what I would have recommended.

vlad

Oct 29, 2013 at 07:18 PM

Oh man, I wanted to hear that wonderful story.

Erika Tarte

Oct 29, 2013 at 07:30 PM

Guess it just wasn't meant to be, and the DTs are now my CX wheels. On a related note, I have some used Gatorskins w/ low mileage that I'd like to be rid of...

David Yang

Oct 29, 2013 at 08:09 PM

Erika Tarte said:

Guess it just wasn't meant to be, and the DTs are now my CX wheels. On a related note, I have some used Gatorskins w/ low mileage that I'd like to be rid of...

Thierry Bonnaire

Oct 29, 2013 at 09:41 PM

I got a second offer from Piermont connection for this Powertap. Should I go for it??

http://www.ebay.com/itm/121204034560?ssPageName=STRK:null:IT

Craig Zolan

Oct 29, 2013 at 09:54 PM

Thierry Bonnaire said:

I got a second offer from Piermont connection for this Powertap. Should I go for it??
http://www.ebay.com/itm/121204034560?ssPageName=STRK:null:IT

I'd say yes. I just had my SL+ rebuilt with a G3 internals and so far so good. The hub is essentially brand new. New bearings, axle, freehub, strain gauges and electronics. The only thing you'll have to worry about in the future is wear on the brake track of the rim at which point just rebuild the wheel with a new rim (and spokes if desired). The alternative is to buy a new wheel from Neuvation or elsewhere which will run you about $750-$800.

mperlberg

Oct 29, 2013 at 10:35 PM

Someone is selling an ant+ quarq and garmin cheap on the nyc cyclocross Facebook page.... just saying

Thierry Bonnaire

Oct 29, 2013 at 11:36 PM

Thanks Mike for the tip but I would prefer getting a Powertap since I own 2 bikes for training and racing.

eragot

Oct 30, 2013 at 01:02 AM

It is super easy to swap the gxp crank. I too have two bikes for racing and training. Not even 5 minutes. The price is great and someone should snap it up.

David Yang

Oct 30, 2013 at 01:43 AM

FYI 172.5.

Marc Bertucco

Nov 01, 2013 at 09:02 PM

Neuvation's having a sale this weekend. And it appears a bit better than their usual pitch. So, CX wheel experts...

If I was to buy some trick carbon tubulars for CX, what should I choose?

mugwump

Nov 01, 2013 at 09:49 PM

Start with the alloy. Switching to carbon is a commitment. You haven't been on tubs for years and years, and it's a big change in terms of care and feeding. You'll need to switch pads each time you go from alloy training wheels to carbon race wheels and then back after the race. you'll need to be a little more careful with the care of the wheels and the tires. And the cross season is three months long, so you should probably also consider what you would want to race on the road with.

Even if you get them next week, getting tires and having them glued on will add another week or more, so you'll have them for a month of this season or less.

Rushing on a commitment like carbon tubulars is unwise.

dstokes

Nov 02, 2013 at 01:43 AM

C50 carbon tubulars. I used then for both road and cross.

Swapping the brake pads is trivial