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Quote:

Originally Posted by I_like_cereal (Post 12420546)

Running a 12/25 soon a 12/27 with a 53/39. I have a 30 for a bail out. I am trying to not use it.

The cranks turn easy. No way am I Lance Armstronging at 90 rpm more likely 60 - 70 rpm.

I turn comfortably for the hour or so commute. I generally sit for the entire commute I only come out of the saddle for a really hard hill. I'd say that one is 8% or 9% over 500 or 1000 feet. On that one I have to come out of the saddle. I can sit for whole hill, but it is a struggle.

Again thanks. I learned a lot. I think I will put a 25 on the back and a 23 on the front. I think that will give me the contact patch I need on the back and the aero on the front to help with the aero.

I am going to work on lower strength and conditioning. Thanks.

Put 25s or 28s on both wheels. Tyre aero buys a marginal edge at +25mph. At slower speeds it matters less than rolling resistance, which is lower for wider tyres:

http://www.bikeradar.com/news/articl...e-myths-29245/

Also your front tyre is the one that matters most contact patch wise for steering and braking.

In fact, just forget about bike aerodynamics. Go into the drops for pedalling into the wind, yes, but don't fiddle with the bike. Almost all aero improvements come from rider position. After that the biggest aero advantage are disc wheels... which can save a triathlete about ONE MINUTE in a 40km race. (http://www.beginnertriathlete.com/cm...articleid=1099) A great investment of $1500 on a commuter bike... not!

You have a bail out gear, but refuse to use it because you want to struggle up a hill? The goal is to be comfortable when you climb. Use the saddle and bar to direct the energy to the crank. Stay smooth. Get a smaller front chain ring and toe clips if needed. Leg strength will come with time if you maintain good riding technique. It takes months to pickup 1-2mph on a climb.

My Cannondale has tight geometry, but I can still squeeze in 28C. It may be a little tight at the back. Do not over-inflate the tire...no more than 80psi if you're 150lbs and ride 28C or larger. You don't want to bunny-hop the bike. A tiny head wind will wipe out any minute edge in tire performance. Aero is not a factor when you climb hills.

I did use the bail out gear, but I stopped because it felt "harder" to maintain cadence than it does with the 39/25. I feel more comfortable with the 39/25 than the 30/25. Odd? I think so, but I can keep a more equal cadence with the 39/25 than the 30/25. It may change with the new wheel I had to get yesterday.

The bike already feels lighter in the rear. I know because I carried it 3 miles this morning. With the old wheel my should would have been hurting really quick from the frame digging into my shoulder.

My other thread about rims blowing out. Has become Shakespearian. Part comedy, part tragedy.

Quote:

Originally Posted by I_like_cereal (Post 12422598)

That's perfectly valid. A lot of MTBers climb in that cadence, and San Fransisco couriers. furballi's advice is based on commonly accepted wisdom derived from the cadence of pro road racers. When applied to other groups of cyclists it turns out to be garbage:

http://www.pponline.co.uk/encyc/cycl...nt-rider-42241

In fact, I can estimate your power output at around 100W from your climb speed, and your cadence is about right for this power output. (And I'd have made the same mistake as furballi until recently.)

Quote:

Originally Posted by furballi (Post 12422436)

It takes months to pickup 1-2mph on a climb.

A lot depends on personal metabolism, but with the right training you can speed up very quickly at first. *Then* gains get slow, because you've taken the easy ones. At this stage I'd say that an improvement of 1 to 2 mph at the end of the first two months of hard interval training would be realistic.

Quote:

Originally Posted by I_like_cereal (Post 12422598)

Has become Shakespearian. Part comedy, part tragedy.

That would be Twelfth Night, then?

@meanwhile.
I read the article. Good read. I actually saw a guy with those Power Cranks the other day. He swore by them. I thought they looked suspect.

I thought about Qrings, but I thought it was just another thing for your bike. I'll look into it more. I wish there was more date to support this.

I may get a roller for the winter.

http://www.online-cycling.net/article-3.html
Interesting article on Osymetric chain rings.

The graph is what I find interesting.

Quote:

Originally Posted by I_like_cereal (Post 12423231)

Powercranks are definitely suspect:

http://www.bikeradar.com/gear/catego...ranks-11-44574

And eliptical chainrings can only give a very small increase in power. My advice is to interval train, stay hydrated, and have a small carb snack before that hill climb commute.