This procedure applies to Honda 350 models that use the factory metal air box and side covers (We show the installation on a Honda CB350G). The factory air filter arrangement is the same across the 350 family, so removal and installation steps are consistent.
Parts and tools needed
Parts
Side cover grommets (recommended replacement if originals are brittle)
M6 threaded rod or M6 all-thread (for the side cover crossover rod modification)
M6 nuts (standard or nylon lock nuts recommended)
Washers and/or lock washers (stainless lock washer shown)
Tools
10 mm wrench (for the factory rod/nut access)
Basic hand tools for the top mounting bolt and boot clamp screw (screwdriver or driver, depending on hardware)
Note: The video demonstrates one side in detail. The opposite side is the same installation mirrored.
Remove the factory airbox and boot
Remove the crossover rod and metal cover
Remove the side cover needed to access the factory airbox rod nut.
Use a 10 mm wrench to remove the nut from the long rod.
Pull the rod out so the metal airbox cover and assembly can be freed.
What you should see: A long rod that spans across the motorcycle (through the battery box area), which originally tied the factory filter assemblies together.
Remove the top mounting bolt and carb boot clamp
Remove the airbox top mounting bolt.
Loosen the clamp screw that secures the rubber boot to the carburetor inlet.
Pull the factory airbox/boot assembly out and off the carburetor.
Important detail: The factory filter assembly includes a round section that passed through the crossover tube area. That factory crossover connection will no longer be used with pod filters.
Install the angle boot pod filter
Preferred clamp screw orientation
Slide the angle boot pod onto the carburetor inlet.
Position the clamp so the clamp screw is at the bottom for easier access during tightening and future service.
Tighten the clamp so the pod is firmly seated on the carburetor.
How to clock the pod filter for your setup
The pod can be rotated to different angles. Choose the orientation based on your side cover setup:
-
If you are not running side covers:
You can leave the pods pointing outward.
You can also rotate them downward, stopping before they touch the battery box—leave a small gap.
-
If you are reinstalling factory side covers:
Rotate the pods so they face upward.
This improves clearance around the battery box area and the hole that previously supported the factory crossover connection.
Reinstalling side covers with our angled pod filters
Why the side covers wobble after the airbox is removed
With the factory air filters removed, the side covers lose the “clamped” support the airbox provided. The original crossover rod can still pass through the grommets, but without the filter assemblies acting as a solid mounting surface, the covers can wiggle. That movement can cause a side cover to pop off or crack.
The goal is to restore clamping pressure—secure enough to prevent movement, but not so tight that the cover is stressed.
Modification 1: Replace side cover grommets
Replace the side cover grommets before final assembly if the originals are brittle or falling apart.
New grommets provide a more secure, consistent fit.
The video notes these are available new from Honda, and Common Motor intends to offer them as well.
Modification 2: Make a longer crossover rod to clamp covers
The factory crossover rod with brass ends is typically too short for this setup because it no longer clamps against the factory filters. Use a longer M6 rod so the covers can be pulled snugly together.
Options
Make a rod from round stock and cut M6 threads.
Use M6 all-thread from a hardware store (easiest option).
Target rod length (from the video)
Approximately 10 3/4" in overall length.
If cutting threads into a custom rod, thread length shown is approximately 5/16 in.
Hardware stack
Washer and/or lock washer
M6 nut (nylon lock nut suggested to reduce risk of over-tightening)
Optional: acorn nut if you want a more finished look
Rod specification
| Item | Spec | Notes |
|---|---|---|
| Crossover rod thread | M6 | M6 all-thread is an easy substitute for a custom-made rod. |
| Crossover rod length | ~10 3/4 in (target) | Video states just under 10 3/4 in; “10 11/16” is also mentioned. |
| Thread length (if making your own) | ~5/16 in | Not needed if using all-thread. |
Assemble and tighten without cracking the cover
Install the pod filters (both sides) and confirm the pods are clocked correctly for side cover clearance.
Install the longer threaded rod through the side cover grommet and across to the opposite side.
Install the washer/lock washer and M6 nut.
Tighten the nut only until side cover movement is minimized.
Caution: Do not over-tighten the nut. Excess pressure can crack the side cover. Tighten only enough to prevent wiggling.
Final checks
Confirm each pod filter is fully seated on the carburetor inlet and the clamp is tight.
Confirm pod filter orientation clears the battery box and allows side covers to sit correctly.
With side covers installed, confirm there is minimal movement at both the top mount and the crossover rod/grommet area.
Verify no hardware is rubbing on the pod filter body or side cover.
Troubleshooting
Side cover still wiggles after installing the threaded rod
Confirm the grommets are in good shape and properly seated in the side cover.
Confirm the rod is long enough to engage threads with washer and nut installed.
Tighten slightly more, but stop as soon as movement is controlled.
Side cover won’t fit with the pod filter installed
Re-clock the pod filter upward to improve clearance for side covers.
Confirm the pod filter is not contacting the battery box; rotate to maintain a small gap.
Clamp screw is hard to reach after installation
Reposition the clamp so the screw sits at the bottom before final tightening.
FAQ
Do I need to install pod filters on both sides?
Yes. The motorcycle uses mirrored intake/filter setups. The video demonstrates one side and notes the opposite side is the same process mirrored.
Can I run the pods angled down or straight out?
Yes, if you are not running side covers. If you want to reinstall the factory side covers, the pods typically need to be clocked upward for clearance.
Can I reuse the factory crossover rod?
You can physically reinstall it, but it will not clamp the side covers securely once the factory air filters are removed. A longer M6 rod allows the covers to be tightened down to reduce movement.
How tight should the side cover nut be?
Tighten only enough to stop the side cover from wiggling. Over-tightening can crack the cover.