Alpha Slack-R Headset Angle Kit 1.5°

Name: Alpha Slack-R Headset Angle Kit 1.5°
Brand: 9point8
SKU: ALPHA-IS41
Price: 109.0 USD
Availability: InStock

ALPHA-IS41

$109.00 USD

Shipping calculated at checkout.

Complete to start customizing

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What Brand is your Bike?

Specialized Other

What configuration is your upper bearing?

Type A Type B

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Product Options

IS Standard

IS41

IS42

IS42S

Quantity

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The 9point8™ Slack-R™ headset angle kit changes the head tube angle on bikes with IS headsets. (IS41 and IS42* upper bearing and IS52 lower bearing only.)

CLICK HERE FOR MORE INFO ON IS41 vs IS42 vs IS42S

Confirm the three checks below and complete the drop down menus to see what Slack-R kits are available for you.

1. Confirm your headset is the IS Standard
If you are not sure, read this article on headset identification by the experts at Park Tools.

2. Confirm you have enough steer tube length to install a Slack-R
If measurements A + B are greater than below there is enough steer tube to install a Slack-R

3. Measure or look-up your bike's head tube length (HTL)
Bicycle manufacturers often list your bike's HTL in geometry charts on their websites. You can also measure this yourself as shown below.

What does installing a Slack-R do to your bikes geometry?
Click HERE to take a deeper look.

Want more customization?
Add additional parts to your Slack-R Kit to fine tune your HTA and test the extremes with one of our angle sets. Individual parts located HERE.

**Important Compatibility Information**

**MUST READ**

Slack-R is now compatible with MOST Tapered IS headsets. There are 3 different styles of upper cups now to go along with the IS52 lowers. IS41, IS42, and IS42S.

IS41/IS52 will fit a number of bikes from manufacturers such as Yeti, Santa Cruz, and Trek (eliminates the need for a Knock Block in most cases). Cube is an exception as they use a deeper upper bearing seat and the Slack-R IS41 will not sit properly in the Cube frames.

IS42/IS52 will fit many bikes from Cannondale, Norco, Marin, Orbea, GT, Revel, Scott and many more including some Specialized with a standard depth IS42/IS52 headset. Standard bearing seat depth is 3mm

IS42S/IS52 will fit Specialized bikes that have the 6.8mm deep upper bearing seat. (some Specialized bearings sit deeper than the standard IS42 geometry so they require their own specific top cup to insure proper fitment)

Headset types do vary across the same manufacturer, make sure you are sure what kind of headset you have. (IS/EC/ZS or hybrids of these)

Some IS bearing seats in the frames have a smaller bearing seat inside diameter than others so in some cases a bit of sanding will be required to fit in the 34.5mm upper sleeve and 44.5mm lower sleeve. In most cases the frame allow the kits to drop right in but in some cases opening up the upper and/or lower bearing seat inside diameter(s) will be required so double check your frame clearance prior to ordering if unsure.

Contact support@9point8.ca if you are unsure about your application prior to ordering.

Does your bike have a Trek Knock Block headset?
The Stop Chip must be removed from all Trek Knock Block headsets before installing a Slack-R. Read more here.

Kit	HT Length	Upper Cup	Min L	Max L	Lower Cup	Min L	Max L	Tensioner	L
ALPHA	90-98	0000-1343	22	26	0000-1349	25	29	0000-1345	43
BRAVO	100-108	0000-1343	22	26	0000-1349	25	29	0000-1346	53
CHARLIE	110-118	0000-1343	22	26	0000-1349	25	29	0000-1347	63
DELTA	120-128	0000-1343	22	26	0000-1349	25	29	0000-1348	73
ECHO	97-105	0000-1343	22	26	0000-1350	32	36	0000-1345	43
FOXTROT	107-115	0000-1343	22	26	0000-1350	32	36	0000-1346	53
GOLF	117-125	0000-1343	22	26	0000-1350	32	36	0000-1347	63
HOTEL	127-135	0000-1343	22	26	0000-1350	32	36	0000-1348	73
INDIA	110-118	0000-1344	42	46	0000-1349	25	29	0000-1345	43
JULIET	120-128	0000-1344	42	46	0000-1349	25	29	0000-1346	53
KILO	130-138	0000-1344	42	46	0000-1349	25	29	0000-1347	63
LIMA	140-148	0000-1344	42	46	0000-1349	25	29	0000-1348	73
MIKE	117-125	0000-1344	42	46	0000-1350	32	36	0000-1345	43
NOVEMBER	127-135	0000-1344	42	46	0000-1350	32	36	0000-1346	53
OSCAR	137-145	0000-1344	42	46	0000-1350	32	36	0000-1347	63
PAPA	147-155	0000-1344	42	46	0000-1350	32	36	0000-1348	73