MegaSack DRAW - This year's winner is user - rgwb
We will be in touch
I've just replaced the XT 44 tooth outer ring on my XT Octalink crankeset with a Deore M510 44 tooth outer ring. The M510 ring is supposed to be compatible with Mega9 chainsets. However, the arms of the ring are rather wider the the arms of the XT's spider (the arms of the orignal XT ring flowed into the spider seamlessly). The Deore ring has the correct BCD and is held in place correctly by the chainring bolts so, apart from looking slight odd am I likely to have any problems?
I was a bit suprised by this as the XT cranks are already fitted with steel Deore 510 steel inner and middle rings which fit into the spider as did its original XT rings.
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The overlap isn't a problem. But it looks like the distance between the middle and inner ring looking down on the chainset once it is mounted might be narrower than it should be, so shifting might be a problem. It looks like the outer chainring is mounted further inboard than the original was from the shadows on your photo. In the end, there's only one way to find out and that's to ride it.
I'll have to give it a ride and see (I'm still waiting for the volcanic ash cloud to subside so my frame can arrive). I was pretty sure that Mega9 Octalink rings were compatible (the inner and middle Deore rings work fine) but it might be worth sticking the XT ring back on if it's going to be problematic.
You should be OK. Give it a go.
I think having your crank bolted into that shoddy grass would be a bigger problem 😈
The arms of the XT ring are thicker so the spider does stand a little proud of the Deore ring but I can't tell by eye whether this means the Deore ring is any closer to middle ring than the XT was, I suspect not but I'll have to give it a go when the bike's built up.