Spotlight: K9 Industries Angled Reducer Cups +/- 2º Headset cups

K9 Industries Angle Reducer Cups
K9 Industries sent over some of their 2º angled reducer headset cups for us to check out. The K9 headset cups allow the user to modify the stock geometry of their bike by changing the angle which the fork attaches to the headset. Read more inside on the details of the K9 ARC cups and what they have to offer.
Most downhill bikes currently are using a 1.5″ head tube. K9 has machined headset cups that allow these users to easily modify the head angle on these bikes. With riders desiring slacker head angles (or steeper in some cases) from their current bikes, there aren’t many options built into most bikes that allow these riders to change their head angle. The K9 ARC headset cups fulfill this desire and come in a wide variety of sizes and angles to fit most every bike out there.
The first step to do is measure the 1.5″ head tube length of the bike you wish to install the K9 headset cups into. They currently make ARC headset cups to fit various head tube lengths. You can email them if you’ve got a question about compatibility with other sizes as well.
- 4.625” head tube length (+/- 2º)
- 5.000” head tube length(+/- 2º)
- 5.250” head tube length(+/- 2º)
- *additional head tube lengths often work as well and +/- 1º ARC cups are being made. Contact K9 for details and questions.
The ARC kits are only available for bikes with 1.5” head tubes, and convert the 1.5″ headset from 1.5” to use a fork with a 1 1/8” steerer tube. The K9 ARC setup comes standard with a Cane Creek IS3 integrated headset that presses into the cups right out of the box. No additional headset pieces are needed for installation or usage which keeps things simple.
K9 includes some detailed instructions to help ease installation. It’s important to heed their suggestions as these cups need to be aligned properly. There are guide marks on the cups themselves that are used to line the headset up correctly.
Specifications:
Cup Material: 6082-T6 Aluminum
Finish: High surface finish with a hard anodized gray color and Anodic printing.
In the box: Set of Angled Reducer Cup, Integrated Cane Creek IS3 Headset (black), Cane Creek Interlock headset spacers (plastic), K9 Engineered Component decals and fitting instructions.
There are many benefits that these cups can offer those seeking a slacker (or steeper) head angle. By using the K9 ARC in –2º mode, it can help provide additional stability in high speed sections, lower the bottom bracket, lengthen the wheelbase, as well helping to add additional stability in steeper terrain.
There is a flip side to this as well to consider before jumping to setup your bike slacker. All trails don’t necessitate slacker head angles and sometimes can be a bad thing just as easily as a good thing. Using these headset cups certainly isn’t for everyone and is quite dependent on the conditions the rider is riding in.
Weight:
| Manufacturer | Model | Year | Real(g) | Desc. | Pic. |
|---|---|---|---|---|---|
| K9 | ARC 2º Headset Cups Only (5″ headtube) |
2010
|
72 |
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|
| K9 | ARC 2º Headset with CaneCreek IS3 complete |
2010
|
159 |
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|
| Cane Creek | IS3 Headset (bearings, race, and compression) |
2010
|
50 |
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Price
- In the USA / Canada contact Jim at Obtainium Performance Products jim@obtainiumperformanceproducts.com
- Everywhere else check with info@k9industries.com
Check out our Complete K9 ARC 2º review here.
A slacker setup isn’t always better but those who are seeking to change their bike to a slacker setup should definitely consider the K9 ARC headset cups. K9 gives the user more control in their bike setup and that is always a good thing in our book. If you need more information, contact info@k9industries.com










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any word on installation? alignment may be tricky… ?
Installation is not as easy as a non angled setup but they’ve made it almost as easy as it can be. They recommend using some tape to help get it aligned properly with the cuts in the cups. Shouldn’t be a problem for a qualified shop or mechanic.
I like the idea of being able to steepen the HA on some DH bikes. Not everyone has the terrain for <64 degree HAs
If you don’t have the terrain for a slack bike, then why are you riding a dh bike to begin with? Surely if it’s not steep, then something with less travel would work better for your purposes.
I have a 2008 Giant Trance which I think needs to have a slacker head angle for me to enjoy rather than survive some of the trails I ride. (Giant has slackened the head angle on the Trance since then.)
Question would it better to fit a longer travel fork or are the K9 Reducer cups really what I’m after. Currently a Fox F100 but I have a Pace RC41 XCAM (in need of a service) whic would give an extra 40mm of travel raise the front significantly (may be a problem) and slightly raise the bottom bracket (would help).
This can definitely find its place on the the new giant glory. Stock, the frame has a 66 deg HA so -2 deg would make it spot on for DH.
The new Giant glory has a tapered headtube though so using these on it wouldn’t work as these are designed for a 1.5″ to and bottom cup. I hear one is in the works though…
My head tube is 4.750″. Which kit should I get?
I’d measure the headtube to get the actual height and then contact K9 and ask them which ones they’d recommend.