Stem User Guide
Please read below for detailed instructions on installation, care and maintenance.
General Specs
Hardware:
Each stem uses M6x20mm steel hardware for the steerer clamp. Ranger stems use M5x20mm steel hardware for the faceplate but every other stem (Hifi, BZA-35, BZA-DM, Director) use M6x20mm steel hardware for the faceplate.
Each stem uses a 4-bolt front loading pattern and same-side stem pinch arrangement.
All stems have MAX Torque specs etched onto the stem body. Note that MAX torque specs are just that, a maximum rating. They pertain to the stem only and do not consider the maximum torque rating on the handlebar, which may be lower. They are not the ultimate guide for torque and before installing, the user should check the handlebar ratings for torque recommendations. In cases when the stem torque rating and handlebar torque rating do not agree, the lower value should be used.
Faceplate gap: Chromag stems are designed to have a gap at both top and bottom sides of the faceplate. The installer should ensure that the gap at both top and bottom is the same.
Compatibility
Bar Diameter:
- Ranger, Hifi and Director stems are only for use with 31.8mm diameter bars only.
- BZA-35, BZA-DM stems are only for use with 35mm diameter bars only.
Steerer Diameter:
All Chromag stems are designed for a 1 1/8" steerer tube, the standard for modern suspension forks. Stems can NOT be modified or interchanged to fit a different steerer tube size.
Direct mount:
Chromag direct mount stems are designed to fit the forks with "Boxxer crown direct stem standard” fork crowns only. Most modern dual-crown forks, including those made by brands other than Rockshox, use this pattern.
Carbon:
- Please refer to fork manufacturers guidelines when using a fork with a carbon steerer tube.
- Please refer to bar manufacturers guidelines (torque spec) when using a carbon bar.
RIZA / Headsets:
While the RIZA is compatible with all 1 1/8" threadless headsets, care must be taken to check the entire face of the stem makes even contact with the headset top cover. If it does not then a spacer is needed between the stem and the headset.
Installation
Tools required:
4mm & 5mm allen (hex) keys, torque wrench.
***installation and service by a qualified mechanic is always recommended***
Preparation:
Make sure the fork steerer tube extends at least 36mm from the top of your headset or the top of the required headset spacers. Alternatively, you can leave the steerer tube long enough to extend entirely through the stem, and use spacers above the stem. The latter configuration can be preferable as it ensures maximum overlap between steerer and stem, and also allows room for the adjustment of the stem position for rider preference. With either configuration, the stem or spacers should extend a minimum of 2mm and maximum of 3mm beyond the top of steerer tube. This gives a compression gap to ensure adequate clamping surface.
Inspect that there are no sharp burrs on the steerer tube. File and sand as necessary. Ensure steerer is clean and dry (no grease). Use alcohol or similar cleaning agent.
Slide stem onto the steerer tube until it touches the headset/spacers. Make sure the entire face of the stem makes even contact with the headset, if it does not then a spacer is needed between the stem and the headset. Stem must protrude forwards from the bike when the fork crown is lined up perpendicular to the frame and the axle in front of the bike.
Install top cap and compression bolt. Adjust the compression until any play is removed from headset but the fork rotates smoothly. To check for play, apply the front brake and rock the bike forward and backwards while gently holding fingers around the top of the headset. If there is noticeable play then snug the compression bolt a little more and check that the fork still moves freely. The compression bolt should never be so tight that the fork does not rotate freely.
Line up stem in line with the front tire and tighten the steerer clamp bolts (Chromag stems come pre-greased but always check and grease the threads if necessary) using a torque wrench fitted with 5mm allen key (hex) head. Refer to the torque specs that are laser etched on the stem – Maximum 8Nm on Chromag stems. NOTE THAT THESE SPECS ARE MAX ONLY AND FOR MOST PURPOSES, 5-6NM IS ADEQUATE.
Mount the handlebars in the stem, ensuring that bars are centered. Tighten faceplate clamp alternating between the four bolts in a cross pattern, a small amount at a time, until recommended torque is achieved on all 4 bolts (refer to torque specs etched on the stem faceplate). Chromag stems are designed to have an even gap between the faceplate and stem body at both top and bottom of the faceplate. Note that uneven or incorrect tightening of stem faceplate bolts can damage or lead to premature damage of the handlebar.
TIP: The torque specs on the stem are the maximum allowable torque for the stem bolts. Going above the maximum torque written on the stem may cause the bolt to break. Check the handlebar and fork manufacturer guidelines before tightening as the fork or bar may have a lower allowable torque than the stem bolts (particularly if components are carbon). In the case that torque specs do not agree between components, always use the lower value. Carbon friction compound between the stem and bar and steerer tube (if one is carbon fiber) is advisable and can reduce the need for high torque in order to secure the fixture.
Before riding check that all bolts are tight. Perform a twist check (clamp front wheel between your thighs and vigorously twist the bars; the bars should not move).
Care and maintenance
- Check inside of stem for burrs or nicks before mounting a bar. Chromag stems have bevelled edges to reduce the stress at clamping joint.
- Regularly check bolt torques.
- Regularly check for fatigue or damage, especially after an impact or crash. (discoloration, cracks and dents)
- After a crash, the stem may rotate on the steerer tube. This is normal, and does not necessarily mean that the steerer clamp bolts or top cap compression bolt is too loose. Loosen the steerer clamp bolts, orient the stem to point forwards, and re-tighten the steerer clamp bolts. DO NOT attempt to adjust the stem orientation without first loosening the hardware.
- Do not modify any Chromag stem.
- Do not exceed the bolt torque specs on the stem AND the fork and bar manufacturers torque guidelines. Lightweight fork steerers or bars can be damaged from excessive clamp force.
- Do not use inferior or lower standard hardware than the supplied hardware. Do not use shorter bolts than the 20mm bolts that come with the stem, as full thread engagement is very important to the strength of the stem.
- Use carbon compound friction paste if using a carbon fiber bar or steerer.
- Stems are only compatible with the diameter bar and steerer tube that Chromag specifies for each stem. Do not use for alternative sizes or modify to do so.
Warranty
Chromag stems are covered under limited warranty for a period one year of the original date of purchase, or as per the laws of the local region of purchase. The warranty applies only to the original owner and covers the product only in the case of manufacturing defect. It does not cover products damaged due to normal wear and tear, abuse, negligence. Damage resulting from crashing or extreme stunt riding is not covered under warranty. Surface finish, colour change or fading is not covered under warranty. Warranty claims must be returned to Chromag or the dealer where the product was purchased. Warranty claims must include the original purchase receipt.