Headset extension spacer with fastener? What is that for?

[Ugo51]

Hi guys,

Not too long ago I bought a Marin Bear Valley which sported this fairly cumbersome setup:

What is the function of that locking spacer that sits under the extension tube? Do you reckon the previous owner just used it as an additional spacer, or does it need to be tightened? Because when I do so the steering locks up...

Thanks

 

[MRGRUMPY]

Re:

That is a steerer tube extender. It clamps to the steerer and the stem clamps to the extender.
The clamp does need to be tight.
The very lowest clamp is part of a Diatech headset which is a conical chape washer that takes the place of a star nut, and adjusts the tension of the headset bearings, although it looks as if a star nut has been fitted to the fork.

 

[Ugo51]

Re:

Thanks.
Yes, the top one is the extender, the shiny tube with two allen fasteners.

So the one at the bottom would work like the star nut...interesting. So I guess it would need to be tight.
But, as you pointed out, I already have a star nut, so does it mean I can leave the conical washer loose?

The reason I want to keep it is that I want to get rid of the extender, but if I also take away that washer the handlebar will be too low.

 

[petitpal]

I'd guess it was wanting to lift the handle bars up combined with not wanting to cut thr steerer tube. Fpr my money I'd get a riser stem to lift thr bars to where you want them to be, and yhen cut them down. But that's just me - sure plenty of other people would take a different approach.