Re:
hmmm....
Last weekend I messed up whilst rushing and left a spacer out of my cassette - and when I realised I managed to get to an LBS near the forest, who kindly removed the cassette and installed a replacement. I also knew as I watched the guy spanner it back on that he was tightening WAY too much, and had a long handled Park tool to tighten the locking. He was pretty grumpy about doing the job just as the shop was closing, so I bit my tongue and said thanks - and was genuinely grateful since it had saved the ride. And so the next day out came the chain whip and my hyperglide tool that goes onto a 3/8 drive, with quite a long handle. Nothing. Would not budge. So out with Shimano tool, which I can clamp into the cassette with an axle, leaving just a little bit of play, Then a mahoosive Bahco adjustable spanner - long and HUGE. And with ALL my weight on it and and the chain whip, with the Grom leaning on the wheel......still nothing. So, finally align chain whip and spanner so that I can get both hands round both and PULL them together....and that did it. A LOT of force needed.
Then cleaned it, since grit jams them on, replaced locking with plenty of COPPASLIP anti seize, and just tightened a few clicks. Done.