Bike Forums

Bike Forums (https://www.bikeforums.net/forum.php)
-   "The 33"-Road Bike Racing (https://www.bikeforums.net/33-road-bike-racing/)
-   -   Racer Tech Thread (https://www.bikeforums.net/33-road-bike-racing/956936-racer-tech-thread.html)

mattm 05-19-15 05:24 PM


Originally Posted by globecanvas (Post 17819458)
SRAM is marketing 1x11 for crit racing now. It's kind of not a bad idea.

I'd say it's a bad idea if you want to use the bike outside of crit racing.. like for training and such.

Even I use a small ring every once in a while!

carpediemracing 05-19-15 05:46 PM


Originally Posted by globecanvas (Post 17819458)
SRAM is marketing 1x11 for crit racing now. It's kind of not a bad idea.

I rode for most of a season with a 1x10 set up after a front derailleur problem in a race. I didn't bother fixing the thing because, you know, crits. Made training a bit more tricky. I was super thankful for the option to shift into the small ring, even though I *ahem* never need it. That season taught me that I want the small ring. May not "need" it, for my training, but definitely want it.

notwist 05-20-15 06:33 AM

Does anyone have experience with the SRAM WiFli rear derailleurs? My bike currently has 2011(?) SRAM Force. Would I need to replace anything else other than the derailleur itself?

I'm planning on doing Catkills (and some other hilly RRs) and was thinking buying a long cage derailleur and 11-32 cassette might be easier/cheaper than buying a completely new crank. Plus, i'd like to have the power numbers from my Quarq to look at. It's a 130bcd so my chainring options are limited.

globecanvas 05-20-15 06:44 AM

You might need a longer chain as well, definitely not anything else though. Depending on your crank it might be just as easy to swap in a compact as it is to change the RD, cassette, and chain. Thought the quarq might be the deciding factor there.

Wylde06 05-20-15 06:58 AM

I could get away with a 1x11 here.

Doge 05-20-15 08:20 AM


Originally Posted by Dutch Jazz (Post 17819028)
Correct me if I'm wrong here; but if you are saying that friction = power lost, doesn't that mean that 45x12 is better than 52x14, because the chain makes contact with fewer teeth. Fewer contact points = less friction = less power losses?

Couple more things to add (my beating a dead horse personality).
Higher cadence is similar to larger rings/cogs. More teeth come into play and the chain tension is lower. (There is more bearing and human movement energy when spinning - a different conversation.).

If you've has a fixie, track bike, tandem sync chain that is too tight (the eccentric adjustment) you may have experienced it is quite hard to spin. I don't know where each friction component comes into play, or how much each contributes but between the chain/gears/bearings and frame flex it is a lot. The tandem sync chain over tension I am very familiar with and the tension that produced lots of friction (20W area) was about the same we'd get putting out 300W.

topflightpro 05-20-15 01:12 PM


Originally Posted by notwist (Post 17821525)
Does anyone have experience with the SRAM WiFli rear derailleurs? My bike currently has 2011(?) SRAM Force. Would I need to replace anything else other than the derailleur itself?

I'm planning on doing Catkills (and some other hilly RRs) and was thinking buying a long cage derailleur and 11-32 cassette might be easier/cheaper than buying a completely new crank. Plus, i'd like to have the power numbers from my Quarq to look at. It's a 130bcd so my chainring options are limited.

I have a Sram Apex Wifli RD, an 11-32 cassette and a longer chain for going out to the mountains. The 39-32 combo is equal to a 34-27. It works ok. The shifting isn't great - due in part to the cheaper quality components I am using and in part to the big gaps between the cogs on the 11-32. But it allows me to keep power when riding in the mountains.

But year, putting a compact crank on is an easier task. I just don't also have a compact SRM, nor do I really need a compact full time around here.

caloso 05-20-15 01:30 PM

I put a 45t chainring on my son's bike because X-12t cassettes are a lot cheaper and easier to find than X-14t cassettes. Since he's 11, he's not wearing it out with massive watts. Not yet, anyway.

Edonis13 05-20-15 02:30 PM


Originally Posted by notwist (Post 17821525)
Does anyone have experience with the SRAM WiFli rear derailleurs? My bike currently has 2011(?) SRAM Force. Would I need to replace anything else other than the derailleur itself?

I'm planning on doing Catkills (and some other hilly RRs) and was thinking buying a long cage derailleur and 11-32 cassette might be easier/cheaper than buying a completely new crank. Plus, i'd like to have the power numbers from my Quarq to look at. It's a 130bcd so my chainring options are limited.

I have the wiFli Force 22 with a compact on my Tarmac and I have nothing bad to say about it. You will just need the RD and a longer chain.

mike868y 05-21-15 08:02 AM

i hate shoddy bike shop work. just realized the shop that assembled my bike (grolby - not our shop. i was young and dumb last year...should have went to our shop) didn't use any carbon paste on the compressor plug in the fork so it was slipping when I tightened the top cap...helps to explain why it's been damn near impossible to keep my headset tight for more than a few weeks at a time.

echappist 05-21-15 09:19 AM


Originally Posted by notwist (Post 17821525)
Does anyone have experience with the SRAM WiFli rear derailleurs? My bike currently has 2011(?) SRAM Force. Would I need to replace anything else other than the derailleur itself?

I'm planning on doing Catkills (and some other hilly RRs) and was thinking buying a long cage derailleur and 11-32 cassette might be easier/cheaper than buying a completely new crank. Plus, i'd like to have the power numbers from my Quarq to look at. It's a 130bcd so my chainring options are limited.


why not get a Sram VIA GT and run a 11/36t cassette? It's in the style of a road derailleur, so you won't have to worry about the lack of barrel adjusters, etc

fwiw, I'm running a 50/34t and a 11/36t for a race this weekend. Last time i did the race i was doing 75 rpm avg on a 34x28t, with quite a few minutes bogged down to 65 rpm at 4.65 w/kg for the particular section and 4.25 w/kg FTP. Having a 36t would allow me to spin up at my normal climbing cadence of 90-100 rpm, and the worst section would be 85 rpm, assuming the same w/kg.

echappist 05-21-15 02:48 PM

anybody wants pie? Got a plate here

https://lh6.googleusercontent.com/-G...o/IMG_0266.JPG

globecanvas 05-21-15 02:53 PM

Those wheels don't go with that cassette.

Hermes 05-21-15 03:57 PM

You have me beat. I have a 30t on the rear. However, the wheels are a better match.

http://i170.photobucket.com/albums/u...psn7t4gqih.jpg

Homebrew01 05-22-15 06:02 AM


Originally Posted by echappist (Post 17826148)
anybody wants pie? Got a plate here

https://lh6.googleusercontent.com/-G...o/IMG_0266.JPG

Jeepers !! Loaded touring bike ?? Mt Washington ?

topflightpro 05-22-15 06:37 AM

Have any of you guys swapped out SRM spiders onto different cranks?

I ordered a Cannondale SRM spider for my Hollowgrams. I have the tools needed to swap the spiders, so that is not an issue. But SRM says I should really send it to them for install, and I really don't want to wait for them to do that. Is it really necessary I send it to them, or will everything work fine if I install myself?

tetonrider 05-22-15 11:11 AM


Originally Posted by topflightpro (Post 17827616)
Have any of you guys swapped out SRM spiders onto different cranks?

yes.


Originally Posted by topflightpro (Post 17827616)
Is it really necessary I send it to them...?

no.

it's a simple job if you have the tool and know what you are doing. that said, many people have zero mechanical skills and can both it. just don't over tighten and mess up the lockring.

tetonrider 05-22-15 11:15 AM

on a tangent, the design of the cannondale MTB SRM units required a modified lockring removal tool. it's not necessary for the road units or, if memory serves, the 1x MTB units...but the 2x MTB units had a thicker spider. a few turns on a lathe would modify a tool.

doesn't affect you, but just wanted to be clear that self-install is not always trivial because people think they have the right tool but actually need a custom one.

echappist 05-22-15 12:38 PM


Originally Posted by Homebrew01 (Post 17827544)
Jeepers !! Loaded touring bike ?? Mt Washington ?

Tour of Tucker County in WV. 3.5 mile finishing climb, first 1.1 at 12%, and i really prefer to spin.

Hermes 05-22-15 12:44 PM

Put my 54t on my TT bike and recalibrated the Quarq using Qalvin and a known weight. Raised the slope by 1.27%+. The zero offset changed from -170 to +34. According to Quarq, the zero offset change is okay and due to the changing of the ring i.e. loosening and tightening of chainring bolts. It is okay as long as it does not vary by 50 units from the start to the finish of the ride.

Fudgy will still kick my ass (a lot) on Saturday. So it goes.

mike868y 05-22-15 01:48 PM

Tour of tucker county is...fun?

hack 05-22-15 02:26 PM


Originally Posted by Hermes (Post 17828862)
Put my 54t on my TT bike and recalibrated the Quarq using Qalvin and a known weight. Raised the slope by 1.27%+. The zero offset changed from -170 to +34. According to Quarq, the zero offset change is okay and due to the changing of the ring i.e. loosening and tightening of chainring bolts. It is okay as long as it does not vary by 50 units from the start to the finish of the ride.

Fudgy will still kick my ass (a lot) on Saturday. So it goes.

I think Quarq would also say to expect a bit of zero offset noise for the first few rides while things settle.

Hls2k6 05-23-15 04:24 AM


Originally Posted by Doge (Post 17815177)
I believe the tests, but think about how you will be racing and those tests may not be as relevant to you. Aero bikes are not the most predominant in the pro peloton.

I love reading about this stuff. Especially stuff from Josh Poertner, who has written tons about perception vs. reality, especially in the pro ranks. Two of my faves:

Lightweight climbing wheels and the 6.8 kg limit at the Tour (Page 2): Triathlon Forum: Slowtwitch Forums

Lightweight climbing wheels and the 6.8 kg limit at the Tour (Page 5): Triathlon Forum: Slowtwitch Forums

Doge 05-23-15 08:39 AM

I am not aware of all that data those links cite. The data I have seen is TT and lab based, not riding in a pack based. That would be hard data to get I expect, but my guess is it is being calculated / guessed. The pros have gone aero 50mm profiles generally over 30s and over 80s. Add some gusty side winds and those different profiles can really be felt, contrary to what those slowtwitch articles were saying.

tetonrider 05-23-15 11:09 AM


Originally Posted by Doge (Post 17830640)
I am not aware of all that data those links cite. The data I have seen is TT and lab based, not riding in a pack based. That would be hard data to get I expect, but my guess is it is being calculated / guessed. The pros have gone aero 50mm profiles generally over 30s and over 80s. Add some gusty side winds and those different profiles can really be felt, contrary to what those slowtwitch articles were saying.

josh pertness knows his stuff and is pretty transparent. those posts were from 2 years ago and some things have changed.

basic message -- and it is a bit different for true pros v amateurs -- is that these guys don't have to choose between light and aero due to the 6.8kg limit......so "light" is pretty dumb for them. there are a few circumstances (for amateurs) when it matters, but even those are rare. (uphill only and even then above a certain grade.)

agree that handling comes into play, and it could be that the 80mm profiles are just enough heavier that 6.8kg becomes a bit harder to meet with them. those profiles can be a handful in certain winds and descents (IME), and could result in slower times despite being more aero. ~50 with modern rims is pretty much no big deal, even in the mountains (descents)...and i'm just a hack.


All times are GMT -6. The time now is 06:03 AM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.