Help me choose a cassette.

johnnyc71

I'm buyiny a road bike.

It will have an Ultegra compact (50/34) fitted. The cassette choice:

11-23
12-25
12-27

My current hybrid is 48/36/26 with a 12/26 cassette fitted.

I'm not sure on what cassette to get, I was thinking 12-27 or 12-25. What do you guys suggest?

I currently cycle 80 miles a week on rolling roads/hills. Will the 12-25 suffice? Fitness is ok (ish) I can cycle 15 miles at a 14.3 mph average - no problems.

davelakers

Personally I would go for the 12-27. I cant think of any reason to need a 53/11 combo unless you are racing. The 27 will make a big difference on the hills.

While we are on the subject of cassettes, Im buying a Trek 1.9 with a 105 -10 speed cassette on the back. Its got Ultegra everything else so I was wondering can I fit my current 9 speed Ultegra (12-27) on the back?

Smokin Joe

Apart from the fact that the gears won't index because the cassette spacing is different, why on earth would you want to do that? Just get the dealer to fit a cassette with your preferred sprockets.

davelakers

Smokin Joe wrote:

Apart from the fact that the gears won't index because the cassette spacing is different, why on earth would you want to do that? Just get the dealer to fit a cassette with your preferred sprockets.

It probably is a dumb question, but when it comes to these things I am!!

I didnt know if there was a way round it. Obviously not!!

azzerb

Go for the 27, if you don't ever use the 27 then it's no big deal, as you just lose a couple of inbetween cogs. If you went for lower but couldn't use you might find it not as enjoyable to ride.

If you do find the 27 easy, just ride it with confidence and when you wear out the cassette buy a different one.

johnnyc71

Think I'll go for the 27 - makes sense really - thanks for the help. BTW this is for a Planet X Sportive Ti. I hope I will be making a good choice for my first road bike.