Forum

[Deanobats]

Result! Amazing what you can find out in your garage with a torch at 10pm on a Saturday night. It was a very slightly loose pinch bolt on the right hand fork guide, leading to a few mm of play in the wheel spindle. This only manifested itself as being loose at a precise point when turning the steering and only when the wheel was loaded by the fork end sliding about an eighth of an inch along the spindle - that was my 'clunk'. I'll wait for daylight to sort that one out...

[Deanobats]

Well, it never rains but it pours. I did a little research on t'interweb and apparently this is a bit of a common problem, that the pinch bolts can't be done up tight enough to grip the spindle on the right hand fork side. It's a 6mm bolt and a few people have reported that to do it up tight enough, you often break the bolt or strip the threads. Roll forward this morning, and one quarter extra turn on the nut and....stripped thread in the nut. Now I can't even get the buggar off. A few people had reported drilling out the 6mm hole to 8mm and putting an 8mm bolt in instead. First I'll remove offending bolt (I imagine much swearing will ensue) then I'll take stock of the situation. I don't know how true it is, but some people have said that the later C5 classics already have 8mm pinch bolts.

[Dennis C]

Dean, for goodness sake the bike is under guarantee, take it carefully back to the dealer show them what is loose and let them sort it, they do get paid to carry out guarantee repairs so keep quiet about tightening it yourself. If the bolt has to be so tight and still not gripping the spindle something else is wrong and needs sorting a new oversize bolt will not make it right.

[Les]

Is this the type of fork you have and is this the pinch bolt in question my concern would be by fitting a larger bolt and using much more force is there a chance of the fork breaking, a known problem like this should be brought to the attention of the dealer if you modify it and the leg breaks it could be a bit risky and could also cost a lot of money



[center]

[Les]

Because of the importance of this issue I have just been out to the shed in my slippers and found on my bike a 12mm socket fits the pinch bolt in my photo, I think that would make it an 8mm bolt, I have only checked it for size not tried to tighten or loosen it my bike was registered 1st Jan 2014 and is the Classic 500 Bullet so most probably manufactured some time in 2013 I hope this may be of some help

[papasmurf]

A pinch bolt is just what it states on the tin. They should not need much torque on then to do the job. If one isn't doing the job something is drastically wrong. The bore and the shaft that goes in it should be very close to being the same size for the pinch bolt to clamp them. Something is badly wrong if you have to overtighten a pinch bolt.

[Deanobats]

Thanks everyone, jobs a good 'un. Old one came out nice and easy, miraculously I had a spare (lucky I live by the motto of never throw anything away - who would have thought that bit of ford Focus would prove so useful?), nicely tightened and it's fine. I might treat myself to one of our host's stainless steel versions though. My forks are different to yours Les, the spindle leads the fork bottom by about an inch and a half. Interestingly, our hosts list the pinch bolt for a classic as M6 too, though another forum suggests they were later changed to M8 because of he need to tighten them hard.

[papasmurf]

Deanobats, a pinch bolt should be tightened to the specified torque and no more. Especially with anything aluminium which could fail catastrophically as a result.

[Deanobats]

Do you know if the torques are listed in the workshop manual? It looks like a heck of a lump of alloy to be clamped by a 6mm bolt.

[PeteF]

Look, something very wrong here. That pinch bolt should need hardly any torque, certainly not enough to strip the nut. If anything you should need to pry the split apart to move it. It looks to me like either the fork leg ID is too big or the spindle OD is too small. It's in warranty! Take it back! He should have spotted that the first time.