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[papasmurf]

PeteF I agree pinch bolt should not need wrenching tight to grip, something is badly wrong.

[papasmurf]

Deanobats, the problem could also be causes by the bolt not having enough thread for the nut to tighten enough.

That would explain other people having the problem. A batch of the wrong length bolts that side of the production line at the factory.
(I have had similar problems several times in the past with bolts.)

[Les]

I am with Pete and Papa on this one, on all the bikes I have had when you tighten the spindle up nothing moves about, the pinch bolts are then just nipped up, if the spindle is fitted and tightened correctly any movement means a problem of some sort, I do not have any experience of the type of fork you have on your bike, I would certainly get it confirmed by the dealer that is how they are if it is that would be a surprise to me

[Deanobats]

Thanks guys,
it's going back to the dealers to get looked at. I put another bolt on it last night and nipped it up to 9 NM torque which is about right for a dry 6mm 8.8 grade nut and bolt. It seemed to do the trick but I took it out for a spin this morning and the 'clunk' is back as the pinch bolt isn't tightening the fork end onto the spindle properly. I would have expected a tighter fit between the spindle and the hole in the alloy fork end, but with no pinch bolt in there you can just slide the fork side to side along the spindle by a few mm so you would need to apply some force to pinch the fork ends onto the spindle. There's no obvious looseness if you apply the front brake and rock the bike back and forth, so it's not far out, but it doesn't feel right to me. I'm just posting this for information now in case any other B5 EFI owners look in as it has been mentioned on a few other sites (thanks Google), so it may be a bit of an issue with some new bullets and it's not an obvious thing to spot. The clunk only happens when there is load on the front wheels, and you only find out why if you grab the right hand fork end and pull outwards with quite a bit of force, then you notice it's loose.

[Deanobats]

If this works, this is what the end of the forks looks like...



If is doesn't work, it's not what the fork ends looks like. Hmmm, reminds me of a two Ronnie's sketch.

[Deanobats]

Just in case anyone needs it, the workshop manual lists the torque for the M8 pinch bolts on a C5 classic front forks as 33 Nm. No mention of the thinner M6 B5 pinch bolts on B5 bullet, but as most charts give the maximum torque on a dry 8.8 grade M6 (as fitted to Lola) as around 10 Nm, I figure that's about right.

[nigelphoto]

1) Take it back - 2) If you're going to muck about with it buy a torque wrench - 3) Read this https://www.imperialsupplies.com/pdf/A_ ... Charts.pdf

[Gaz262]

Deanobats? - Shouldn't the 2 flats on the spindle be in-line with split for the pinch-bolt? Your photo shows the spindle looking like it needs rotating a few degrees clockwise to engage the flats inside the fork leg... Maybe that would allow the spindle pinch-bolt to tighten properly onto the spindle shaft with more surface contact.
Just my two-pennorth m'lud....

[Deanobats]

Hi Gaz,
the two flats don't go that far down the shaft, the section of the spindle that goes through the fork ends is cylindrical so orientation of them doesn't matter. I'm assuming the flats are there for a spanner to stop the spindle rotating when you undo the nut on the left hand side.

[Gaz262]

Right! - I was assuming the flats were there to be grippied by the fork-leg - Whoops!................................I'll get my coat.