Does such thing exist?
I'd love one 😀
how many arms on your crank?
I have an xtralite one on an old XT 5 arm 94BCD
and druidh linked to this 4 arm 104 BCD the other day.
It woudl appear they only do 104mm BCD nowadays though
http://www.extralite.com/index_euro.htm
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Get an old 5 arm crankset or spider. I'm running middleburn 20,30,40 on a Surly Mr Whirly. It's great.
Middleburn do them.
The 4 arm 30t chain rings often require the crank to be ground down.
They were common on old 5 arm compact cranks, I used to have a TA one about 16 years ago I'm sure...
you'd be too close to breaking through the tooth profile with the chainring bolt hole on a 104 PCD ring, hence 32t seems to be about the lower limit for current "Normal" 104/4 arm cranks
Theres always Middleburn cranks...
Looking at my SLX crank arms I dont see enough clearance and Im running a 32. Any smaller and the spider will hit the chain.
You can go ten speed and 36 at the rear though. Or have you done that already.
31 from here - but you still might need to modify the crank.
http://www.homebrewedcomponents.com/store.php/products/aluminum-104bcd-4-bolt-chainrings
doh I forgot to mention in my post that those xtralite ones are 30T.
Yep, I have one on each of my 2 bikes.
Andersen machine
http://andersenmachine.wordpress.com/product-info/
Extralite
http://www.extralite.com/Products/octaramps_anglo.htm
I prefer the andersen machine personally, it just seems a bit more robust, that being said, I have no complaints on either of them.
As mentioned, bother have required me to file away a bit of material from the spider on my xt m770 cranks.
I suppose you could mount something off of the 64 PCD granny tabs if it a bit of return to bring it back closer to the middle ring position so the chainline makes sense...
Or is that just a bad idea?
I'm assuming this question has been raised by the idea of a for a 1x10 drivetrain (Perhaps using a certain 9-36t Cassette?)
Ten helpful responses and nobody telling him to MTFU? WTF?
in fact thinking about it some more why even go to the faff of making a whole special ring when you could make a 64 PCD/4 arm "Granny adapter" that let you bolt a 5 arm 94 PCD chainring on?
Must be achievable...
you can get down to a 29t with 5 arm 94bcd, have one in my spares waiting for the right project
Cheers everyone I'll see if the LBS can have them 😀
Extralite do the Octaramp Gara to allow you to run smaller rings and offset them, or they do the 30t Octaramp up there. I used to use those (and file the spider accordingly) and they weren't bad.
Not an LBS job though - order direct from Extralite.
MTFU. 52 teeth for real men.
MTFU. 52 teeth for real men.
Among permanent teeth, 16 are found in the maxilla and 16 in the mandible, for a total of 32.
32 FTW, unless you are a shark...