Chainrings

Noclue

I've been on my bike for nearly 3 years and when i bought it i opted for a compact chainset, but as my fitness and strength have increased i find that i hardly ever use the lowest gears when in the granny. If i was to buy a new bike now i'd probably opt for a standard chainset but i'm not getting a new bike and can't afford to buy a new chainset either, so i was wondering if it is possible to fit a larger granny, thinking of a 36t, to my existing chainset and if so could anyone reccomend one for a Shimano Ultegra chainset? Thanks.

pilot_pete

Why bother? If you don't use your current lowest gears one would assume you are not riding steep hills (apologies if you are and are just superhuman!) and the other ratios are ok, then why spend money on another inner ring which will presumably just give more duplicated ratios?

PP

jibberjim

Pilot Pete wrote:

Why bother? If you don't use your current lowest gears one would assume you are not riding steep hills (apologies if you are and are just superhuman!) and the other ratios are ok, then why spend money on another inner ring which will presumably just give more duplicated ratios?

because it will give him a smaller jump between gears meaning he'll find a gear that allows him to ride at just the cadence he wants.

OP - you can buy just the chain rings cheaply e.g. a 36 or 38t inner ring from http://www.spacycles.co.uk/products.php ... b0s149p292

Berk Bonebonce

I dunno what you got at the back, but changing some/all of the sprockets is another option.

And I thought West Sussex had some hills.

Monty Dog

Frankly, it's a regular question and the answer is to learn to pedal faster. You can fit a 36 tooth inner ring no problem or as suggested, change your cassette to something like 12-25 or even 11-23 if you want a more even step between ratios.

Noclue

Thanks for the replies, at the moment i have a 12-25 cassette at the rear so fitting 12-23 could be an option and i do ride some hills, quite a few actually, and certainley when i got the bike i did use the lowest gear to get up them but now find that the 2 smallest rarely get used and it would be nice to have a smaller drop when changing into the granny.

Thanks for that link Jibberjim, they would be ideal and certainley cheaper than either a new cassette or chainset.

Pross

I would go for a straight through cassette but as others have said there are larger chainrings available that will fit. Keep hold of your existing cassette or chainring when you change it as you never know when it will come in handy (you may fancy a trip to the Alps or something).

1_reaper

Noclue wrote:

Thanks for the replies, at the moment i have a 12-25 cassette at the rear so fitting 12-23 could be an option and i do ride some hills, quite a few actually, and certainley when i got the bike i did use the lowest gear to get up them but now find that the 2 smallest rarely get used and it would be nice to have a smaller drop when changing into the granny.

Thanks for that link Jibberjim, they would be ideal and certainley cheaper than either a new cassette or chainset.

Use a 12-23 with a compact and when going up hills of 14% it's hard work. Being slightly heavy does not help

CrackFox

I can recommend these Specialites TA Syrius chainrings. They are compatible with your Ultegra compact cranks.

http://www.dotbike.com/ProductsP1684.as ... aign%3dDDI

John.T

Just fit bigger chainrings. I now use 52/38 110BCD rings on my best bike. I can fit the 50/34 back on in about 10 min if I need to.
http://www.spacycles.co.uk/products.php?plid=m2b0s149p296

http://www.spacycles.co.uk/products.php?plid=m2b0s149p294
As I run my chains as long as possible I do not need to alter the length. If the 50/34 are only going on for a short time I do not drop the front mech either. It does not seem to affect the change much.

Down the Road

36T was the original compact. It was only after talking to Mamil's that Shimano went for the "girly" 34 option.

A 36 is more or less putting one extra gear on the back compared to the old 39 ring. That is why it was originally chosen. It also means you can ride on the small ring a bit more as your "cross over " speed is more realistic.

I would advocate everyone fitting 36 inners on compacts

markos1963

I got a 36t on my compact. It has made it so much better. I have some cruising gears now on the small ring that i never had before. In fact I may even change both rings over and go to a 53/39 set up.

Down the Road

Just change the block in that case

50 x 11 is bigger than 53 x 12 and 99% of us can't turn that at 100rpm

pneumatic

Down the Road wrote:

36T was the original compact. It was only after talking to Mamil's that Shimano went for the "girly" 34 option.

Harsh, but true. My compact came with a 36T chainring and I had to swap it for a 34T to give me better climbing options. In my defence, the thing I was trying to climb was the Mont Ventoux from Bedoin, and I definitely needed the extra help!

this thread makes me wonder, though, whether I should now put the 36T back on for a smoother ride.

BTW, the change to 34 didn't require any adjustment of the front derailleur but I did have to adjust the rear one a little, because the extra chain length caused the jockey wheels to rub.

markos1963

Down the Road wrote:

Just change the block in that case

50 x 11 is bigger than 53 x 12 and 99% of us can't turn that at 100rpm

Granted but it still doesn't address the big jump between rings on a 50/34

Down the Road

Agree that's why it should be a 36.

John.T

BTW, the change to 34 didn't require any adjustment of the front derailleur but I did have to adjust the rear one a little, because the extra chain length caused the jockey wheels to rub.

Why did you lengthen the chain? It is the big/big combination that sets the minimum chain length.
Also it is the big ring size that dictates whether you need to adjust the front mech position.

pneumatic

John.T wrote:

BTW, the change to 34 didn't require any adjustment of the front derailleur but I did have to adjust the rear one a little, because the extra chain length caused the jockey wheels to rub.

Why did you lengthen the chain? It is the big/big combination that sets the minimum chain length.
Also it is the big ring size that dictates whether you need to adjust the front mech position.

I didn't lengthen the chain; I put on a smaller small chainring and that made the chain slacker at the rear than the original setup. Anyway, I found a way to adjust the rear derailleur to cope. Agreed about the front mech issue, just trying to reassure the OP that it can be done without hassle.

John.T

pneumatic wrote:

John.T wrote:

BTW, the change to 34 didn't require any adjustment of the front derailleur but I did have to adjust the rear one a little, because the extra chain length caused the jockey wheels to rub.

Why did you lengthen the chain? It is the big/big combination that sets the minimum chain length.
Also it is the big ring size that dictates whether you need to adjust the front mech position.

I didn't lengthen the chain; I put on a smaller small chainring and that made the chain slacker at the rear than the original setup. Anyway, I found a way to adjust the rear derailleur to cope. Agreed about the front mech issue, just trying to reassure the OP that it can be done without hassle.

OOOOPS. I should read the post better. I took it as going from 34 to 36. :oops:

pneumatic

John.T wrote:

OOOOPS. I should read the post better. I took it as going from 34 to 36. :oops:

Worry not at all. We all make mistakes (as the Dalek said climbing off the dustbin! )