Hood breather tube base/adapter

[joeschuit]

Working on a small project that involves adding a second breather tube on my hood. The first one is 5200'd in place and is fine, but figured this will provide a cleaner and more efficient way of getting air inside the hull. Tubing used is from mcmaster 5500K33, same that's used for rrp and similar pole breather tubes. 2" id, roughly 2-3/8" od. Current plan is to bore a 2" hole in the hood and drill clearance holes using the base as the template. The green bellmouth will be in two pieces and lock together once inside the hole and some adhesive will hold it in place. the base can then be screwed on with some more adhesive on the flange. The internal threads are sized to thread the tubing in. After my earlier flowbench testing airboxes, it was evident how drastic a bellmouth increased the airflow, so I figured if there's room on the inside of the hood I'll find a way to add one in there. I'll use this thread to provide updates on the design and final implementation on a couple skis.

 

[WFO Speedracer]

Thanks for that Mcmaster number I needed to replace the tubes on my 650SX fixie hood , are you 3d printing these adaptors
?

 

[Big Kahuna]

I need to order some for my rickter pole................ Thx for link

 

[mikesx]

Working on a small project that involves adding a second breather tube on my hood. The first one is 5200'd in place and is fine, but figured this will provide a cleaner and more efficient way of getting air inside the hull. Tubing used is from mcmaster 5500K33, same that's used for rrp and similar pole breather tubes. 2" id, roughly 2-3/8" od. Current plan is to bore a 2" hole in the hood and drill clearance holes using the base as the template. The green bellmouth will be in two pieces and lock together once inside the hole and some adhesive will hold it in place. the base can then be screwed on with some more adhesive on the flange. The internal threads are sized to thread the tubing in. After my earlier flowbench testing airboxes, it was evident how drastic a bellmouth increased the airflow, so I figured if there's room on the inside of the hood I'll find a way to add one in there. I'll use this thread to provide updates on the design and final implementation on a couple skis.

Have you considered making the green bellmouth 1 piece with a slit in and then corkscrewing it into the breather hole? May not even need adhesive then….

 

[joeschuit]

Adapters are 3d printed. Pla for fitment and petg for the long term. A slit bellmouth sounds like an excellent idea. it's about 3.5" in diameter and 3/8" tall so there should be enough flex to allow that.

 

[brapperdoodle]

This is champion! How it should be done

 

[joeschuit]

Excellent call on the split bellmouth ring. For this hood I'm going to do a 15 or 20 degree angle to the base so the tubes will come together towards the center.

 

[cpolaris502]

Nice! Similar (sort of) to the printed tube mounts I made last year. I used Shop Vac hose for my tubes and didn't want to permanently glue them in since I'm not sure how long they'll hold up, so I wanted an easy way to swap them out if needed. I have this multi-part sliding clamp design that grabs onto the ridges of the hose. I've only got a few ride days on this prototype setup so far, but it worked really well and definitely made a huge difference since my 1105 only breathed through the pole tubes before.