Well thats not going to work!

After the excitement of riding the Polaris Cobra around the yard I figured I'd go all out and take it out on the trail. A quick ride down the street (love living in a redneck town) and I was off onto the trail. I didn't do too much riding, just to the snowmobile shop to hang out and show off. On the way home the headlight quit working which is a common occurrence on this sled, I need to play with the wiring some and see whats up with that.

Anyway the biggest issue with the sled right now is that its really loud. Part of that is the exhaust which I think may have had baffles removed, theres a suspicious weld around the side of the can but mostly its because theres no airbox. Carb noise is a particular whoosh kind of sound combined with a noise similar to the exhaust.

When I got the sled it came with an airbox but the airbox boots were trashed so I built some new ones, the existing clamp inner diameter was about the same as a piece of foam hose insulation so I built new boots with RTV using the foam as a guide. Unfortunately that proved to not fit the carbs so I spent a minute today and actually you know MEASURED things... Turns out the carb mouths are just about 42mm and I happened to have some 42mm radiator hose so my plan was to use RTV to graft the hose onto the existing stubby boots.

Here you can see how the old boots didn't make the gap to the carbs, it was hard to tell at first that the boots wouldn't actually fit over the carbs at all...

Heres my pile of supplies, the airbox, a piece of radiator hose, my micrometer for measuring and other assorted tools and cutters and whatnot.

I cut two short pieces of hose, the one for the PTO carb I cut a little longer than the inner, my intention was to sit the airbox slightly cocked to get away from the clutch.

Okay, confession time, its not gonna work, here you can see the carbs with my new boots installed, I even notched them to fit close on the carb but now I can see that to miss the clutch I'd have to offset the airbox half an inch to the mag side of the engine.

This will require some thought. My immediate thought is to buy a couple pod filters and it looks like I can get them for about $4 each. That would help with the noise a little and would also filter the air going into the engine but I think the PTO side is still going to be a problem.

The other thought I have is to take some PVC pipe and make my own airbox. 42mm is 1.65 inches so I should be able to take 2 inch pipe and fit the rubber boots inside, then mate that to a 4 inch piece of pipe in which I could install some baffles to reduce noise.

My final idea, and the one I think I'll end up with is to stop in at the shop and see what is available for airboxes, maybe they'll have something I can modify to fit.