replacment rear gears cassette

[shakie]

Hi everyone at Cycling Forums, New to these pages and need some advice. Just bought a new road bike a Trek 1.1and am getting on fine with except ( due to my age) I need a lower bottom gear to climb the steep ones,don,t want to spend loadsamoney on this problem so have found on the net some Shimano Acera HG41 8speed cassettes, raitios being 11-30 11-32 11-34. The ratio on my bike I think is 12-25, which one would you advise me to go for? and they the same fitting?. Your help on this would be appreciated me being a novice in this and thanks in advance for your thoughts Shakie.

 

[oldbobcat]

Only your own experience can tell you which cassette range will work best for you.

I can tell you that the 2300 or Claris rear derailleur on your 1.1 will not clear the larger cogs on these cassettes. You will need a Shimano MTB 7/8-speed rear derailleur, Altus or Acera, part numbers RD-M280, RD-M310, or RD-M360, to handle the wide range cassette, and then you will need a longer 8-speed chain to handle the larger cogs and longer derailleur cage.

 

[alfeng]

Originally Posted by oldbobcat
Only your own experience can tell you which cassette range will work best for you.

I can tell you that the 2300 or Claris rear derailleur on your 1.1 will not clear the larger cogs on these cassettes. You will need a Shimano MTB 7/8-speed rear derailleur, Altus or Acera, part numbers RD-M280, RD-M310, or RD-M360, to handle the wide range cassette, and then you will need a longer 8-speed chain to handle the larger cogs and longer derailleur cage.

OR, the OP can change the crankset ...

• if the bike has a "standard" (130BCD) crankset, then a "compact" (110BCD) FSA crankset may do the trick ...
• if the bike already has a "compact" crankset, then a MTB (104BCD) crankset (sans granny) should work ...

a 42t is a bit small for an outer chainring, but a 46t will certainly be large enough for most people when the smallest Cog has 12t.

 

[shakie]

Hi Old bobcat&Alfeng, thanks for your advice on my little problem looks like will have to get the the old legs going a bit more, I must say I am better on this bike than my old one which was only a 12 speed and was2 sizes too big for me !! so will see how I get on over the next few weeks. Have been out clocking the miles up today, getting ready for my first century ride which I had said I was going to do this year but family problems have delayed me, so it will have to be next year now.Thanks again for your interest in this and will let you know when I get my century in.Good riding to both. Shakie

 

[oldbobcat]

Originally Posted by alfeng

OR, the OP can change the crankset ...

• if the bike has a "standard" (130BCD) crankset, then a "compact" (110BCD) FSA crankset may do the trick ...
• if the bike already has a "compact" crankset, then a MTB (104BCD) crankset (sans granny) should work ...

a 42t is a bit small for an outer chainring, but a 46t will certainly be large enough for most people when the smallest Cog has 12t.

1.1s only come with compact double cranksets. These days standard road doubles and triples are usually a special order item, and Shimano 11-speed is all based on 110 mm bcd doubles.

34/28 is a pretty stout climbing gear. By working up gradually your climbing with this gearing will improve without too much pain. The disadvantage of wide range cassettes, especially with only 8 cogs, is big jumps between ratios. And I say "only" being fully aware of the irony.

 

[alfeng]

Originally Posted by oldbobcat
1.1s only come with compact double cranksets. These days standard road doubles and triples are usually a special order item, and Shimano 11-speed is all based on 110 mm bcd doubles.

34/28 is a pretty stout climbing gear. By working up gradually your climbing with this gearing will improve without too much pain. The disadvantage of wide range cassettes, especially with only 8 cogs, is big jumps between ratios. And I say "only" being fully aware of the irony.

Thanks for clarifying what the 1.1 is equipped with ... I didn't know and that is why I qualified by saying "if" before mentioning a 110BCD crank as an option ...

Are those the currently-proprietary 4-arm 110BCD cranks on the 11-speed Shimano equipped bikes or are the traditional 5-arm cranksets the off-the-shelf option?

BTW. Do you know if (for the near term) whether-or-not the prospective buyer of an 11-speed equipped Shimano bike have a chainring option?

I agree that a 34/28 is/(should be) a substantially low enough combination for most climbing situations for most people below an altitude of 7000 feet ... heck, the 28t could probably be considered a bailout Cog when mated to a 34t chainring.

Loaded touring typically needs a lower gear OR for the riders to dismount & to walk their bikes.

 

[oldbobcat]

Originally Posted by alfeng

- Are those the currently-proprietary 4-arm 110BCD cranks on the 11-speed Shimano equipped bikes or are the traditional 5-arm cranksets the off-the-shelf option?

BTW. Do you know if (for the near term) whether-or-not the prospective buyer of an 11-speed equipped Shimano bike have a chainring option?

I agree that a 34/28 is/(should be) a substantially low enough combination for most climbing situations for most people below an altitude of 7000 feet ... heck, the 28t could probably be considered a bailout Cog when mated to a 34t chainring.

Loaded touring typically needs a lower gear OR for the riders to dismount & to walk their bikes.

Y'r welcome.

Shimano's 11-speed uses the new asymmetric 4-arm configuration in 110 mm BCD only. The rings are so stiff that the BCD really doesn't matter.

Currently, 53-39, 52-38, 52-36, and 50-34 are the available combinations when you order Dura-Ace as a complete set, either on a bike or aftermarket. There's also a triathalon/time-trial setup that offers 54-42 or 55-42 rings. What you can get on a bike will depend on the brand. Ultegra offers 53-39, 52-36, 50-34, and 46-36 (for junior race gearing?). I can envision 50-34 being the mainstay Ultegra setup. Also, I'm sure 53-44 or 53-46 Dura-Ace sets will become available to the pros for the northern classics.

As usual, Shimano will insist that rings be bought in pairs for optimum shifting. I'm not sure how important this is. I am sure it won't take long for the Fred market to try a 53-34 setup (with an 11-30 in the back) and get into all kinds of derailleur and chain trouble.

And, yeah, I agree that a 34/28 should get most guys up most hills most of the time. A beginner struggling with this gearing should probably wait til he isn't a beginner anymore before deciding to modify the bike.

 

[shakie]

Hi again you two, have been following your discussion and all your numbers and measurments are way over my head. Just to keep you in the picture, over here in merry England my Trek 1.1 came with Front chainring 50-34 tooth and 12-25 rear cassette.I must say I am getting on with this combination better than my old bike( which was heavy and only a 12speed as i said)so will see how I go.In my local area we have a couple of very stiff climbs and when I get out in the Derbyshire hills they tend to go on for ever (well they seem to anyway) Shakie

 

[alienator]

Hi again you two, have been following your discussion and all your numbers and measurments are way over my head. Just to keep you in the picture, over here in merry England my Trek 1.1 came with Front chainring 50-34 tooth and 12-25 rear cassette.I must say I am getting on with this combination better than my old bike( which was heavy and only a 12speed as i said)so will see how I go.In my local area we have a couple of very stiff climbs and when I get out in the Derbyshire hills they tend to go on for  ever (well they seem to anyway) Shakie

With longer, steeper climbs on a longer ride, I think you should give serious consideration to something like a 12-28 cassette. It's better to have that extra 28 available to you than to end up on one of those steep climbs that seem to go on forever wishing you had an extra gear.

 

[shakie]

Hi,so anyway whatever the problems with the gearing I dicided to just go out and do my century AND DID IT. 7hrs 50mns,dont think thats to bad for a 69y old and the gearing will have to stay the same for timebeing. Thanks for all your advise everyone,see you around . Good biking.Shakie

 

[alienator]

Hi,so anyway whatever the problems with the gearing I dicided to just go out and do my century AND DID IT. 7hrs 50mns,dont think thats to bad for a 69y old and the gearing will have to stay the same for timebeing. Thanks for all your advise everyone,see you around . Good biking.Shakie

Good job. Sometimes "just do it" is the exact gear you need.

 

[oldbobcat]

Way to go, Shakie.