How long a fork shaft for CK NoThreadSet

[wassertreter]

Hello, newbie here.

I recently acquired a late 1980s Colnago Master Piu frame (has a straight, chromed Precisa fork), which I want to build up in the coming months.

What I'm really confused about is the plethora of headsets that's available (need to replace the one it came with). I'm fairly certain my bike has an 1" threaded steerer.

Also, I'm pondering using a 1" Colnago Street carbon/aluminium fork instead of the Precisa. Might be heresy to ask here, but which type of headset would I need in this case? I'm more interested in a retro build with a vintage frame, than a period correct one.

I read up on all the different headsets on the Chris King page, but that only added to the confusion. Any advice would be much appreciated. Many thanks.

 

[1988_Ben]

You're along the right lines. And you're doing the right thing looking for a CK headset. You simply need their 1" nothreadset headset, sometimes known as a 1" Sotto Voce.
Get the anodised colour that matches your paint job. The choice of stem might be trickier but you'll probably get a good price as 1" is the old size.
Having said that, don't rule out a 1" quill to 1 1/8" aheadset convertor. Then you're only changing the stem and can worry about chaniging the forks/headset another day.

 

[wassertreter]

Thanks Ben, problem is the headset is bust and needs to be replaced.

 

[1988_Ben]

Sorry, missed that bit first time round...

Oh well, new Chris King it is then ! At least you can be sure it'll not ever sieze up, and will outlast a nuclear holocaust.

Here's a recent forum topic showing a Sotto Voce matching the Colnago paint job, although the problem with some Masters is knowing which colour to choose from !

http://www.retrobike.co.uk/forum/viewto ... highlight=

 

[wassertreter]

Hah there might have been some confusion on my part just as well.

Can the CK headset you suggested take both, the current Precisa fork, and possibly a (more) modern non-threaded one later?

 

[1988_Ben]

No, the Sotto Voce, or anything that Chris King brand as a 'NoThreadSet', or for that matter, anything labelled as Aheadset can only be used for forks with a threadless steering tube. And even if you tried, your original fork's steerer would be cut down to the stack height of the current headset, whereas for aheadset (threadless forks) the steering tube has to be longer to accomodate both the headset stack height and the stem clamp, which is usually 2 inches more.

So if you're retaining your threaded steering tube forks, you have to buy another traditional headset with screw on top locknuts. I don't think Chris King make anything of this type as they were one of the main companies driving the new 'aheadset' type forward. So you'd be looking at 'new old stock (NOS)' stuff on eBay if you want something decent like Campag Record or Shimano Dura-Ace. It depends what your components are and if you want to match the current groupset.

What did you think of that photo on the link to a recent forum topic ? Did it not tempt you to go threadless ? I think it looks quite nice.

 

[wassertreter]

Thanks for the clarifications, think I got the beginning of a picture now.

I absolutely want to go threadless, and am looking around for a nice fork. Thankfully I'm not in a hurry.

Here's a picture for the record. I might have it repainted though.

 

[wassertreter]

Can I bring this up one last time. I've found a potential 1" fork now, but it's cut already.

How long does the fork shaft need to be (in addition to my headtube length, and whatever the stem needs), so I can use a Chris King NoThreadSet?

 

[daccordimark]

If you use a Chris King NoThreadSet you will need 28mm to accommodate the headset stack height plus the height of the stem clamp plus whatever height of spacers you feel you need to be comfortable on the bike plus possibly 3mm above the stem so you can use a 5mm spacer between the stem and the top cap. The 5mm spacer is needed on some stems like mine where the top clamp bolt is quite close to the top of the stem and would end up slightly above the steerer without a spacer. Then you have to hope you've got the height right. Too high and it's cutting time again, too low and well there's nothing you can do about that.

Also, if you get a 1 1/8th" threadless stem you can use it on a 1" steerer with a shim. Both of mine came with shims for this very purpose.

All that is why I prefer threaded headsets and quill stems (apart from infinitely better looks). Steerer length is then just the headtube plus stack height plus optionally 5mm for a spacer between the locknuts. It's so much easier to adjust stem height with a quill stem and I've never had any problems with them.

BTW Chris King do two types of headsets for threaded steerers, The 2Nut and the GripNut. The latter is more heavy duty. You can still get Campag Record 1" threaded headsets from Parker International for less than £50 delivered too.

I personally wouldn't burden a beautiful frame like your Colnago with a threadless stem.

Mark.

 

[wassertreter]

Cheers Mark, yeah I'm still pondering going more retro vs building the lightest and best performing bike I can afford around this frame, and taking it out for sportives and club races.

Thankfully I'm not in a hurry, but the scale seems to be tipping towards a racy build, I'd just take it out more often like that.