Topic: Replacing the upper triple on a k7

[Jonm99]

Hi,

I have recently replaced my original k7 upper triple with a new billet triple (as well as new bearings from allballs) and I'm scratching my head on a couple of things that hopefully someone more experienced can help out with. Specifically, here are my questions:
1. Although this triple is supposed to be specific to my model, it is about 6mm thinner than the original. Because of this the stem is exposed more than it originally was and I cannot lock the triple in place with the crown nut (too much thread to cover). The seller has offered a swap on a thicker one, but my question is, can I just put a couple 3mm washers in between the spanner nut and triple? Or would there be safety issues with that solution? See below image, crown nut is threaded as far as it can go.
2. The original triple has a pinch bolt to lock itself around the stem and hold the spanner in place. The new triple just slides over the stem and "sits" over the spanner nut. Would just the torque of the crown stem nut over the triple be enough to hold everything in place? Even with some lock tight I'm not sure it would be enough. These sleek looking billet triples without the pinch on the stem seem common practice for cb mods, but I wouldn't want to find myself with a loose triple on the highway...

Any help with the above two questions would be greatly appreciated.

Thanks,
Jonathan

[754]

Spacer would be fine, 1/4 inch is just over 6mm. Some industrial supply places carry machine shims.
 If you can get it underneath , even cleaner.
 Make sure your tree lines up to lower, offset on 77 and 78 is different than the others.

[Jonm99]

Thanks for the quick reply! Any thoughts on the no pinch thing on the spanner nut/stem? Will the torque from the crown nut alone be enough to hold it all together? As far as I can see from the bike diagram, there is no lock nut or any other mechanism in place on top of the spanner, but this makes sense as the triple does the job with the pinch. Question is,  do I need to compensate for the lack of a pinch on the spanner somehow...

[rotortiller]

How does the top aftermarket tree clamp around the chrome fork tubes? The pic does not show a pinch mechanism in that area.

[DaveBarbier]

How does the top aftermarket tree clamp around the chrome fork tubes? The pic does not show a pinch mechanism in that area.

There is a pinch mechanism on the other side of the triple. We can't see it in this picture. Hard to explain, but for each fork it uses two locking wedges with a bolt. Quite strong.

For the OP, looks like a Cognito Moto triple. The pinch bolt for the center stem isn't really required. There is little force that would be pulling the lower triple and stem down. All force (maybe I should say most force) is being applied upwards. The top nut is fine for this. It doesn't even get that much torque anyway. My R6 top triple doesn't have a pinch here either.

[Jonm99]

DaveBarbier is correct, it's indeed a Cognito Moto triple and the pinch is on the rear side.

As for the torque, I was more concerned that the spanner nut would simply loosen up from all the vibration, but anyway, your answer(s) are clear. I'll stick with this triple and stick a spacer / washers in between the spanner nut and triple.

Thanks for chiming in everyone, much appreciated!

[Dracon]

 I ran into this exact issue today while trying to install my new Cognito Moto triple in a ‘78 CB750F. I only need about 4mm to let my nut tighten without bottoming out.

The other thing I noticed is that since the stock triple is raised where it goes over the stem and the cognito moto is all flat, the forks have to be lowered about an inch to sit flush with the top of the clamp.