New to Ebikes Crank removal and new tools to buy


New Member
Hi All

I have recently purchased my first EBIKE, a second hand Gazelle CityZen ebike, 2018 with Bosch performance line motor and 10 speed rear cassette 36-11. I find the gearing is too high, I currently pedal in the lowest gear between 14 and 19 kmh and rarely use any more gears than 4-5th. We are speed limited to 25kmh in Australia. So bought a 46-11 Shimano cassette but will not engage the two larger gears because it hits on derailleur. I am thinking of buying a Shimano SLX m7100 rear derailleur rated to 51 tooth. Is this a good choice?

I am also looking at changing the front chainring to a smaller size as an alternative to changing the rear cassette, because it is very small (14-22 size range to be confirmed once removed) I assume it will need regular replacement.

My collection of bike tools is 20-30 years old and so far I have been unable to get the Miranda crank arm off. It has an 8 mm hex bolt which was easy enough but my crank extractor does not work. I am lookin for advice as the which Park crank arm removal tool and a bosch lock ring removal tool, is suitable?

Also my eyesight is not as good as it was 50 years ago and can you please look at pic of crank arm and advise if it is ready for new crank arm removal tool to be used or is there a washer in there that I need to remove?

Thanks for any information and have a good day


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    miranda crank arm.jpg
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    bolt and my extractor tool.jpg
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