Big rings

[astar92]

I am thinking of gearing up my alpinestars cro-mega for a bit of road use so im looking at putting the biggest chainring i can fit on it.
going by the old dx manual the capacity of the front mech is 26t my granny ring is 24t so in theory i should fit a 50t ring on it.
before i go out and find one though I wondered if anyone had tried fitting a ring of this size difference particuarly to an alpinestars frame where adjustment of the front mech is limited by the tab that it fixes to ? thanks

 

[feetabix]

Admittedly I've never fitted one to a position limited mech but I've ran 50 tooth rings on several slick tyred road biased mountain bikes and it does make things better........2 extra teeth over the standard set up shouldn't cause a great problem though, I wouldn't think the standard set up would be right on the outer limits.......

 

[feetabix]

An 11/23 rear block is good for this too.......they are available and take away the low gears that you won't touch on Tarmac........

 

[FluffyChicken]

I run 24-48 at the front and 11-28 at the back and have done since way M737 came out. Admittedly just a standard retroMTB but another two teeth at the front wouldn't harm it.

 

[astar92]

thanks for the advise, yeah I have seen that 11-28 cassetes are available so im going to give one of those a go and keep a look out for a nicely priced 50t chainring so if anyone has a cheap one for sale please let me know and I will post back how it works out

 

[jimo746]

The last MTB that I used a lot on road I fitted a road type chainset to, other than the bigger rings it still looked pretty retro (pics in my Dyna-Tech Diablo build thread below). I used it off road with the same gearing too.
Even A few teeth extra on the front can make a noticeable difference, although like Fluffychicken I have used 48T front with 11T rear for years on MTB, even with slick tyres fitted its rare I'd run out of gearing.

Why not ditch the front mech and run a big single ring up front? Its one way to build up your leg muscles !

 

[FluffyChicken]

Given it a 24T at the front. I assume it's a 110BCD ring you're after.

If so I have 50/52/54 new rings.

 

[astar92]

cool yeah its 110 bcd i believe on a standard shimano triple crank what make rings are they and how much would you be after for the 50t ?

 

[FMJ]

My LBS still has 110s in the 60+ range.

 

[drystonepaul]

One of the great things about modern compact road chainsets is that they mostly use the old non compact MTB size 110 BCD 5 arm chainrings. They typically come with 50 and 34 tooth rings, but there are also loads of replacement options around nowadays.

I have a Ridgeback which is currently set up as a winter road runaround. 50 and 34 up front on Deore MT-60 cranks, an 11-28 cassette and a long cage DX mech.
I used to run a similar set up in the early to mid nineties for getting to and from work. I used an 11-24 cassette back then which worked with a short cage mech with no issues at all.

I don't really see the point of a granny ring on a road set up unless you're touring and or carrying heavy loads.
I can totally see the point of a bigger top gear though.