Can you convert a 135 mm Chris King single speed hub to 142? Yes!

142x12mm Rear ISO SS Thru Axle

If, like me, you've spent good money on a Chris King Single Speed rear hub you've probably found that you've been limited to frames with 135mm rear hub spacing.

However, new frames, like the Niner ROS 9 (which is next on my shopping list!) only come in 142 x 12 spacing. Fortunately for us the chaps at Chris King have realised that 142 is now the default premium mountain bike frame spacing and they're now offering a suitable conversion kit.

Beware! There are two conversion kits

There's the original 142 conversion kit, but it's NOT compatible with your 135 spacing Single Speed hub.

• Don't buy this one: 142x12mm Rear ISO Thru Axle
• Instead buy this one: 142x12mm Rear ISO SS Thru Axle
• You'll also need to buy the High Profile Rear Adjustment Clamp as well to complete the conversion

How to convert the hub

In time I fully expect to make the upgrade myself and will post a how-to guide, but if it's anything like how easy it is to convert a Chris King front hub, then it should be a straight forward affair.

Hope this helps someone.

How to convert a Chris King SD ISO front hub from 9mm to 15mm

Converting a Chris King 9mm ISO hub to a 15mm hub is very easy. I mean really very easy. It takes less than 5 minutes too.

The tools you'll need

• Two 5mm allen keys
• Long 2.5mm allen key (a long allen key will help with bearing adjustment with the wheel on the fork)
• Some lube / light grease
• Clean rag

The parts you'll need

1. Chris King Front Axle 15mm for Small Diameter ISO Disc Hubs
   Product number: PHB324
   
2. Chris King Low Profile Adjusting Collar for Small Diameter Front ISO
   Product number: PHB702
   

NB: These items will not work with the "LD" or Large Diameter ISO hub, which is the 20mm variant of the Chris King ISO hub.

How to remove the 9mm axle from your Chris King ISO hub

• Put a 5mm allen key in each side of the hub
• Turn the non-disc side anti-clockwise
• You may need to put some pressure to get them started (Chris King even recommend to place one allen key in a vice!)
• Once loose, completely remove the non-disc side cap
• Firmly grasp the disc side axle (only use your hands) and give it a good pull
• Once loose, the axle should then pull out quite easily

How to fit the 15mm conversion kit to your Chris King ISO hub

• Ensure that the hub is clean
• Apply any new grease/oil/lube to the bearings as needed and ensure they are still moving freely
• Apply a 10w synthetic oil, Chris King ring drive lube, or as I've done, a regular dry conditions lube to the o'rings on the axle
• Insert the axle in from the disc side and push all the way through
• Grease the threads of the axle on the non-disc side and then screw on the bearing adjustment cap
• Spin finger tight and then back it off 1/16th a turn (a 'smidge' in common parlance)
• Tighten up the 2.5mm screw
• Push the end cap on and it should click into place
• Insert into your fork and tighten as appropriate

Adjusting the bearing

If you've fitted your fork and the bearing is under too much load, i.e. the wheel is not moving as freely as it should, you should back off the bearing adjustment cap.

• Unscrew the 2.5mm allen key bolt
• Move the bearing adjustment cap in an anti-clockwise motion another 'smidge'
• Re-do the bolt and check for play and smooth spinning
• Repeat until happy

If you've fitted your fork and there is play, i.e. the wheel has a wobble to it, then you need to tighten up the bearing.

• Unscrew the 2.5mm allen key bolt
• Move the bearing adjustment cap in a clockwise motion another 'smidge'
• Re-do the bolt and check for play and smooth spinning
• Repeat until happy

Hope this helps someone. Feel free to ask any questions in the comments section.