Did you ever get this off out of interest? I've attempted removing my sprocket carrier from my NC30 today and last night and just no joy. I used a puller, LOTS of WD40 including soaking overnight, parafin, lots of heat (bearing in mind the bearings within - pun intended) and some whacking with a brass punch on the reverse of the carrier but nothing.

Clearly not enough copper slip has been used and its welded itself onto the axle any other suggestions? I was removing to repack the bearings and replace the rear disc, but for the meantime i've had to replace and use new pads with the old disc.

Finally got this off using a load of heat and very tight fitting socket with very long bar!

I will have to have another go at this sometime. Bike passed the mot so another year to sort. There is a tiny amount of play in my rear bearing so need to strip and clean, and I encountered the same problem; removing the chain and hub nut, caliper etc and the sprocket carrier would not come off the splines at all, even with heat and an overnight soaking in copious amounts of WD...

I look forward to this job again sometime soon [/sarcasm]