6 speed to 7 speed

dsmiff

Want to put 7 speed shifters and new cassette on an Trek mt-60 (20in kids bikes) shifters are from another bike (revo) - can I fit a Shimano HG50 7 Speed Cassette (11-34 - wanted a low gear for steep hills) currently has 14 - 28 6 speed.

Also BB knackerd, what BB do I need to replace it - its a "bmx" style one.

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Unknown

7 speed cassettes are wider, so you may need to respace the hub which will mean redishing the wheel. I dont think its worth it to be honest - just get a 6spd block from Halfords. As for the BB, a cup and cone type, I am pretty sure they use 1/4 bearings. if the cups have gone its a job for the LBS.

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dsmiff

Thanks again, put the shifters on today and replaced all the cables (brakes and shifters) today, the shifters still work with the 6 speed - all runs like new now, going to get the youngest up to llandegla soon so wanted bike to be in good order.

Will sort out the BB with LBS.

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