Hi,

I wondered if I could get some help.

The problem started when I noticed the entire drive train slips forward when I apply any pressure through the pedals, a few days later and the cranks/cassette/chain would move freely as if the freehub had completely gone.

I then took the freehub off and cleaned it and re-installed it, it was catching again but I still got the original drive train slip.

I replaced the freehub and the chain and the problem seems to have improved slightly but still get an annoying slip.

Any advice on what it could be? I replaced the chain rings last year and so my only other thought would be the cassette?

Does this "slip forward" happen in any/all cogs or just one or two? I wonder if you had two issues initially. A worn chain/cog so there was common skip under power (and with only a new chain this could still be happening) and also freehub body ratchet pawl skip/unable to engage. Your freehub cleaning might have fixed #2 but #1 might still be at play. Andy.

Thanks for a quick reply Andy

It seems to happen when I am in the middle of the cassette today, I had to stop testing as I realised it's probabaly not wise during rush hour! I cannot remember if it was happening in any other cogs.

I replaced my freehub as I thought the ratchet pawl was the issue but to no avail.

It sounds as though it may be the cassette in need of replacing. I am taking it to my LBS later for a visual inspection.

Sure sounds like a worn cog/new chain skip. I'll bet the skipping in on cogs you use a lot?? Good step to get pro eyes on it. Andy

Thanks Andrew, that is correct it's on cogs around the middle of the cassette. I went to the LBS and they confirmed this too. New cassette ordered!

Thanks for your help!