Help on extending the stem

[NetworkMan]

Glad that's cleared it up. I was coming to that conclusion after asking about the locking collar. It seemed too much of a coincidence that you had both the locking collar and no star nut. Sheldon Brown describes the version you have (Diatech) and also a more sophisticated one (GeForce) that provides a more precise method of adjustment:- https://www.sheldonbrown.com/headsets.html about 2/3 down the page. I suspect that the Diatech will be a pig to adjust but that's for another day (until you slacken off the collar!).

[backnotes]

Sorry I mistakenly called the star (fangled) nut a star washer above. You may get a blank look if you ask for a washer.

Hope you now enjoy riding your new bike. There can't be another of these 20-ish year old bikes in such near-new condition!

[fixerupper]

I want to make the handle bars higher on my Rock Hopper , it looks like I need the same bit of kit ,will it work on this ?( click on image for full size )

[cyclop]

That looks like a threadless headset to me.I can,t see any locking collet device therefore a simple stem extender as per Brucey,s first photo(either black or silver) would work.

[gregoryoftours]

Hi Backnotes, that's it exactly, 100%, and being 'old school' 50 years ago as a kid on my bikes one had a 3/8 long bolt at the top of the stem and once tightened it felt safe and secure and would've held the Titanic, being 6' 2" tall and 209 lbs I felt the need to fit the long bolt supplied with the new stem, but couldn't, No star washer!! and like you say IMHO a cheap way of saving mone, I'll have one fitted by the local LBS for peace of mind, thanks for tracking down the line drawing and your time, BTW a picture of the bike, as explained, it's an old one but mint and I really do need the exercise and people are more friendly out there, image.jpeg

The fitting of a star nut will then enable you to use the long bolt and top cap supplied with your steerer extender to pre load the headset in the same manner as other normal types of aheadset, not have to rely on pushing down on the stem as shown in the installation instructions for your headset, so you should be able to get a better adjustment. Plus there will be the added bonus of the extra security of the long bolt, even though properly torqued clamp bolts should ensure that it will never be doing any work after initial pre load.

[fixerupper]

Oh right thanks for that cyclop...I will have a nose about in the LBC's and see if I can find one in black , if not they seem cheep enough on the bay ...am I right in thinking that you can add or subtract the rings until you find the sweet spot as it were ?