Thanks Malv. I was planning to try and get similar group names going on, but presumably Shimano model-numbers are OK to mix within Deore etc? I've had a look at the various videos of removing cranks, and I really can't see how a decent gear/bearing puller (this is the kind of thing I'm on about btw, comfortably strong enough to pull gearbox bearings apart from a car) couldn't do that easily. Thanks for the tip on the brakes, I thought it might be something like that. I'll have a look at the rear bearings, maybe just slap a load more grease in them just to help protect it from dirt and moisture.