It's a cleaner, not really a lubricant. I've done a lot of work on bikes for a job and we would never put wd40 on anything. Get some legit grease too, it's alright to use wd40 then wash and grease the bearings but I wouldn't use it as a lubricant.
dont use it. go to the skateshop and go grab some bones speed cream. awesome stuff and the bottle lasts forever. Also, you can use white lithium grease, just 2 little dabs in each bearing. Keeps them running for ever and they are SO quiet.
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