I have an elderly, 20 year old M3. When folded, as soon as it is picked up the front wheel and bars will come loose and swing out. The hook is intact, and the the stays for the front mudguard aren't bent. Any Ideas please.
No, the seat post goes fully down.Can the seatpost be pushed down any further?
Done.Picture please
Initially, yes.Does the hook engage with the chainstay properly?
Indeed, I have just had a proper look again and the stopper disc is not there.Possibly you have lost the stopper disk that is attached behind the rear brake or it needs adjustment. When you drop the seat post and lift the bike the stopper disk is blocked by the seat post and hinders the rear frame from dropping and as a consequence the folded bike disassembling the folded package.
Glad it was an easy fix.Indeed, I have just had a proper look again and the stopper disc is not there.
I have had the bike for 18 years, bought second hand, and although this problem did occur occasionally, it now happens every time.
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