Integrated headset sizing help

[Mojoman]

Looks like I have finally found a frame, this is what was sent to me for the hedset specs...
Will this headset from Evo fit (I am fitting a straigh steerer fork, I already have the adapter from Evo bikes)
https://evobikes.co.za/product/kcnc-headset-pt1860-integrated-1-1-8-upper-1-5-lower-black-is42-28-6-l-is52-40/

Im not sure about the stack height? Below is the spec for the frame :

 

Evo Headset tech data:

The KCNC PT1860 is an affordable, integrated headset suited to install forks with tapered steerers in frames with tapered head tubes. This headset features a low stack height of 10mm! Sealed steel bearings combined with high-quality, cnc machined aluminum cups provide a smooth operation and long lasting durability.

Please note:The upper bearing cup has a head tube insertion outer diameter of 41.8mm and the lower bearing cup features an outer diameter of 51.8mm!

The nameKCNC PT1860describes thetapered Ahead headset with integrated cups (drop in). TheS.H.I.S.denotation isIS42/28,6 | IS52/40.

 

Year:	2017
Material:	cups: 6061 aluminum, bearings: steel
Weight:	approx. 98 gram (incl. top cap, bolt and star nut, manufacturer information)
S.H.I.S.:	IS42/28,6 | IS52/40
Construction type (Ahead/Thread):	Ahead Tapered
for fork diameter:	upper:1 1/8″, bottom 1,5″
Stack height:	10mm
Included in delivery:	incl. claw, bolt and top cap

Edited October 1, 2021 by Mojoman

[David Marshall]

That is not the right headset.  Yours does not need cups as the bearing fits directly into the frame.  You need a to get a top part (fully integrated) with a R418 bearing.  That is the top bearing and all above it in the diagram.  For the lower you just need a R413 bearing and the race marked 7 in the diagram.

Headset bearings are a bit of a mine field so I hope this helps.

[Mojoman]

Ja, its quite varied on the headset front....
And there seems to be limited options out there as well...

[Mojoman]

Would this option fit? Limited tech details on this though:
https://www.summitbikes.co.za/index.php?id_product=880&controller=product

 

[Jewbacca]

'MOST' decent bike shops stock all the various headset bearings and almost definitely have a spare bottom race. (I have one if you need).

The top assembly is universal so that should be quite easy to get. I know that Hope sell top and bottom assemblies separately. I bought a Nukeproof one really cheap off CRC not so long ago. 

My advice (as above) is to buy a top assembly and just pop into any LBS and pick up a bearing and race from the  spares drawer

[Mojoman]

Thanks, I did ask the guys to try and sort the headset out before I collect the frame, hopefully they can piece it together but experience has also taught me to assume the worst case scenario....????

 

[David Marshall]

On the Zitto the top part looks right but the bottom is a R425 bearing and you need a R413.  Where are you based?

[droo]

A Cane Creek will do the job, I have stock if you don't manage to source locally.

[Mojoman]

Thanks everyone...