Please Help With A Crankset
 

Hi,
I am new to this forum, and I am sorry if this is posted in the wrong place. I have a 2012 Trek 1.1. I am a runner at heart, but I use my bike to xtrain, and I ride it to work and various other places. I just purchased a Dura Ace 7701 Crankset, used, hoping that it will make the topspeed of my bike faster. I think the crank uses an octalink bottom bracket (im not positive), and I am curious what kind of bottom bracket I need to buy, that will fit my bike and this crank. Thanks for any help.

You need to contact Trek customer service and find out what BB they put on that bike model. If the BB is threaded you should be OK but probably no go mounting to any BB30 derivative.
Personally, I wouldn't have bought that crank for that bike...not a fan of Octalink and economics of that crank will not be favorable after you buy the BB for your crank.

Couldn't you just swap out chainrings?

In most cases, top speed is determined by how fast you pedal. Most bikes have big enough gears that the limit is your legs. Exceptions being areas with very steep downhills.

Does your bike still have the Vuelta Corsa crankset? If so everything I see on google points to it using a standard square taper bb. Which means the bb shell is most likely a standard 68mm english thread. Which means for your DA-7701 crankset you need an octalink v1 bb like the bb-6500 (ultegra) or bb-5500 (105). Stay away from the bb-7700 (Dura-Ace) since it is not a sealed type it will need maintenance.

No I am limited, with the current setup on trek 1.1 I am in top gear, peddling (about 28mph) and I am topped out in my top gear. I need more, want to go faster :)

Excellent, thank you so much. That is what I am looking for. I really appreciate your help :)

You need to learn to pedal at a higher cadence.

Your bike likely has a 50/34 crank, and a 12-25 rear cassette (current spec for a Trek 1.1) That gets you to 29mph at 90 rpm, 33mph at 100 rpms, and almost 40 mph at 120 rpm.

90 rpm is a reasonable cruising cadence, 100 rpm is also reasonable particualrly when your hammering, and 120 rpm is a typical sprinting cadence.

You're not being held back by your gearing. On the off chance you can sustain 33mph on flat gorund without a killer tailwind, for a sustained period of time, your team mechanic should be taking care of your selection of bottom brackets.

All that said,if you must have a higher gear, going to an 11-23 or 11-25 cassette woul be cheaper and easier.

Go Big, Go custom with a 100/80 crankset.
http://bikeforums.net/attachment.php...hmentid=339460

But a standard crankset looks​ much more impressive.

Thanks for the help everyone. I was able to get the bb I needed for 30 bucks. I'm not so worried about looks. I think this setup will work nicely for my commute to work. On the way there its mostly uphill, and I am able to handle them all with my current setup in four gears up from the easiest gear. On the way back there is a 7 mile section where it is about -2 percent grade, and always a really nice tail wind. I have only been able to keep a speed of about 37 (according to my Garmin running watch), and I think now ill be able to pick it up a little more on that section.

Not so much worried about looks. I feel like enough of a bad ass when I complete 50 mile ultra marathons. I don't need an expensive looking bike to make friends or look "cool". Thanks for the help with my bottom bracket question, oh wait you didn't do that. Maybe its time to stop trolling the forums for people to pick on, and go out and ride.

I'm sorry. Welcome to The 41. If you're gonna stick around here, you should learn how to 'roll with the punches'. Just sayin'.... thin skin is only bothersome to the one wearing it. Hopefully this will make it better....

:D

Peace out.

I apologize too. I shouldn't have been so mouthy. I just didn't want to be classified with the people that just go buy new stuff to look cool. Thanks for the apology and for being the bigger person.

I still think you need to learn to spin. You come from running, and are likely aerobically strong, but also likely don't have a good idea of approriate cadence.

FWIW, I'm a Cat 3, so no big deal, but also not slow,at least in a 41 sense. My principal racing bike has a compact crank. I've raced on bikes with compact gears in the Rockies, the Appalachian mountains, and the Sierras, as well as doing some very fast crits in Florida. I've never run out of gear with a compact.

My bet is that if you continue to ride, you'll see before long it's not the gearing that's the limiter.

Hi,

FWIW the assumption you can go fastest is top gear is usually wrong (except big downhills),
and consequently higher gearing will make you faster (except big downhills) also wrong.

On the flat (wind behind), or mild downhill I'm fastest @ 120 rpm in 5th of 7 lowish gears.
Higher gears (except big downhills) will do nothing for me in terms of going faster.

You will find that out. New road bikes are hardly ever undergeared, nearly all are overgeared.

rgds, sreten.