Reflectix Carb wrap

[eric82930]

Here is some info on doing a carb wrap for 2 strokes. It works well enough in most conditions that you can run without carb heat if you have a thermostat and warm the bike up good before you go wide open throttle. I ran for 2 seasons without heat and only had trouble on the most ridiculous cold deep days.
I now just use a 20 watt electric heater drilled into the carb body.

It costs $10 for a lifetime supply (large roll) at home depot.

 

[eric82930]

Pic 1 is the roll of Reflectix. It is foil and bubblewrap. It stands up to a lot of heat but will melt a bit where it directly touches the pipe... so avoid it if you can.

Pic 2 is how I cut it to start out, obviously you might have to try a few times to get the perfect fit but the roll has enough for lots of screw ups. You can't see but there is a slit I already cut for the throttle cable to slide through. The first try will probably fail but you can mark and trim it to use as a template for the 2nd one. The bottom of the picture is the flap that folds under the float bowl.

Pic 3 The idea is to make it fold under and around the back of the carb (under is important) smart folds will limit the amount of duct tape needed to seal it.

Pic 4 shows sliding it in place from the back. you can roll it up to get the top/front sides through the wires and cables then see where it needs trimmed to make it cover as much of the cylinder as possible.

Pic 5 is the wrap with the side flap open for choke and tuning access. Notice the detail on the folds and where I did and didn't need to tape. If you think ahead it can be done real nice.

Pic 6 Is with the side closed I used to just cut a choke hole finger slit but the flap method is way better.

Pic 7 I take a hook and pull the wrap over and behind the hose clamp of the air boot to allow a warm air pocket on the back side of the carb where it needs it most.

Pic 8 Is my home made high flow pod filter. It is also from home depot. It's made with 4 layers of fiberglass pet screen. It is so huge it never clogs even when totally covered I don't loose any HP.

I have used this type of wrap with a stock air box but installation will be more difficult and you could cut a slit into the back hole so you don't have to remove the air boot.

 

[eric82930]

This is the finish product. The skid plate blocks all the pow from the front of the engine and wrap covers sides and rear.

 

[Norma Stitz]

Interesting. I had assumed the carb freezes from the inside out, due to the evaporation of fuel. But the reflectix may hemp hold in engine heat that then warms the carb.

Also I like your foam thing on the tunnel, is that to take up space so to keep snow from packing up there?

 

[eric82930]

Yes your right they freeze from the inside out. And even the bell mounted avid heaters are technically heating the outside of the carb. Luckily aluminum conducts heat very well. Its just a contest to get heat into the aluminum fast enough so it's average temp is above freezing. The humidity has a lot to do with it too. Ive seen carbs frost the outside in low humidity but still runs fine because there isn't enough ice build up to clog the air holes in the bell. Powder days are the worst because of high humidity and the fact that you're wide open all day. Wide open pulls heat out of the aluminum much faster.

The foam is to block the 20 pounds of ice build up on top of my tunnel. The tunnel cover wasn't as good idea as I thought it would be but It does seem to keep me a little drier in wet snow.