new bike supplied with wrong cassette

[Sittingduck]

Sounds like it's not the sprocket that needs work

 

[fossyant]

Got to love the days when I could swap sprockets, and not cassettes. Keep it, and get another ! Like the others have said, you might get a need. It's not a road bike with a compact and a 28 ? - That will ride up walls that will !

 

[fossyant]

i spun out on the new bike when on the old bike i was happy with the 50-11 combination

got to learn to spin

Ohh, Spun out on 50 x 11 on a 27-28 min 10TT - you are not pedalling efficiently at all. I don't spin out on a 53 x 13 (smaller than your 50 x 11) down hill - need about 40mph to do that !

Efficient cadence is between 80 and 100 rpm. If averaging 20 mph I would expect you should be in the 50 x 17 or 16.

Really work on cadence - pedalling speed. You are grinding way too much.

 

[Zakalwe]

What cadence are you doing at the limit? 120-130 should be the upper limit to work towards, maintaining a steady 100 or so for long stretches. 130rpm in 50x12 works out to 68km/h, thats how fast Chris Hoy crosses the line in a sprint.

 

[busdennis]

Ohh, Spun out on 50 x 11 on a 27-28 min 10TT - .

no friend
the 2nd tt i did 27.45 not 27.28 and i didnt spin out, just nearly died
on my first ride on the new bike when i was getting a few miles under my belt i thought " this bikes so much quicker than the old, i feel like i need another gear and guess what, its got one gear less.


note to self. should not get into these discussion when hammered