Highlights:

• Form-fitting press-molded EVA foam & leather shells connected by neoprene+vinyl panels
• Fits like a "skin" to encase your engine PERFECTLY with NO GAP, meaning your engine heat is kept in the engine, not lost to the atmosphere or snow contact
• Best overall heat-retention available - more info below
• Weight: 1 lb - starts light, and…
• Does not create a "cavern" for snow to collect in - STAYS light!
• Considering product weight and snow accumulation weight, NXT Engine Skins can offer a 20+ pound weight savings compared to some competitors, which on a 300+ pound machine with 55 HP, represents the same power-to-weight benefit as adding 2-3 HP! - more info below
• Most compact overall envelope possible - zero impact to ergonomics, and a substantial reduction in snow drag compared to some competitors (snoerodynamic?)
  
• Perfect from December til June - unlike most other options, airflow through rads is unimpeded, so elevated overheating risk is essentially eliminated, without worrying about taking it off partway through the day or carrying extra panels or adding extra coolers
• Installation: 5 MINUTES (two flaps, one zipper, one hook!)
• Easy to live with - simple oil changes, and easy to keep an eye things on-hill (sight glass access preserved)
• Looks are subjective, but wouldn't you say it's the sleekest, leanest, and most NON-pregnant aesthetic out there?

EFFECTIVE - Not a perfect analogy but imagine it like a wetsuit. Focus on limiting the outside effects, so that you retain all the heat inside! Contrast that to a building with the windows open in a snowstorm. On some enclosures the "windows" are smaller than others, but you're still heating a larger area, constantly having to heat new air, and dealing with all the snow that comes in.

Melting snow is BY FAR the biggest impediment to maintaining engine temps. Did you know that it consumes TEN TIMES more heat to melt 1 pound of snow from -1°C to 1°C, than to heat 1 pound of steel from 1°C all the way to 80°C? (remember highschool chemistry, latent fusion and Q=mcΔT? 🤓) If you ever looked inside your old engine enclosure and saw snow, it's a sign that it's struggling to keep up.

FAQ: Why did we focus more on the lower cases than the cylinder head?

• Consider: is your MAIN goal to heat your COOLANT, or to heat the ENGINE itself? The transmission, crankcase, oil sump, etc are areas where your bike will really thank you when they are running optimally, in both performance and longevity. Heat that's getting pulled out of the cylinder (which is obviously a massive heat source) is not really being pulled out of the "engine", it's being pulled out of your "coolant/rads", which is no big deal (oversimplification but I think you get the point).
• You may notice a conundrum where the reading on a coolant temp gauge on an Engine Skins bike could show lower than you expect, particularly if the exposed part of the brass temp probe got snow on it. Again, what really matters is engine temp / oil temp. We actually do keep an eye on our oil temps, with the datalogger we developed for MOUNTAIN MAP ECU tuning - maybe we should develop an accessory so you can too, but you'll have to take our word for now haha.
• The problem-causing "milky oil" you have heard about (or experienced!) is a result of condensation, caused by the engine case being in contact with snow and therefore a large temperature differential occurring within the engine. Like a cold glass of water on a hot day, where the engine cases are the glass of water and the cylinder is the sun. Keep snow off the engine!
• Also, thermal mass. The cylinder, piston, and valvetrain represents less than 15% of the mass of the overall system. That means it will have more effect to GET the lower cases warm, and that they will STAY warm better. In our experience, after a break from riding, Engine Skins bikes are 20-30°C warmer than other bikes.

LIGHTWEIGHT - NXT Engine Skins literally weigh less than 1lb. More importantly, it STAYS LIGHT because it doesn't create a "cavern" for snow to accumulate in! Some of the enclosures we tested were, well, heavy. For example, one 10-15lb system was constantly full of 5-15lbs of snow.

Considering power-to-weight ratios on a 320lb machine with 55 horsepower, you could say that every 6lbs saved has the same effect as adding 1 HP! (or 9.5lbs per HP if you count a 200lb rider too, which probably makes more sense but doesn't seem to be the industry standard haha). We'll let you do the rest of the math on that!

SLEEK - This one speaks for itself I think! It's not just for looks though - if you want to maximize your power delivery, you should be thinking about minimizing the drag of your bike through the snow. NXT Engine Skins are as compact as possible, and the outer synthetic leather is durable and slippery to glide through the snow.

When are you you building Engine Skins for [insert model here]?

Since we've taken an approach that is 100% optimized for each specific bike model, we've of course focused our attention on the most popular bikes. To check availability, use the bike selectors above to choose your make and model. The Skins we already have are available of course, and the ones we have plans for will say so. If the message that appears is not good news for you, I'm sorry. Please do not message us asking for more info - we do not have any extra information in addition to what's posted above. As soon as we do have more information, we will update this page.

One thing you can do, is fill out this survey form. If you're the president of the 2005 YZ250 Fan Club, tell all your friends to fill it out too! If we get a higher-than-expected number of requests for any specific bike, we will consider developing something for that model. To be clear, the survey is NOT an order form and it does NOT mean we are going to develop Skins for your bike.

Thanks for your understanding.

What if my coolant temp gauge reads lower than I'm used to?

Somewhat ironically, since we've focused on keeping the ENGINE itself warm, a thermostat-mounted temp gauge may actually read a lower number than what you're expecting. The reason for this is that without the entire engine bay enclosed in a "cavern", the thermostat can get contacted by snow on deep days. The brass temp probe can have hot coolant on the tip, and cold snow on the hex head. So, the reading the probe sends can be lower than the actual coolant/engine temp.

[insert image here - webpage not 100% finished, sorry] 

What should you do? Nothing, really. Don't worry, the thermostat itself represents a tiny heat transfer area+mass compared to the rest of the system. Just keep all this in mind. If your gauge says 175F instead of 190F, don't stress - rest assured that your ENGINE itself IS as warm as it needs to be, and just keep riding! If it really bothers you for some reason, find a piece of neoprene or foam or something to wrap around the temp probe and thermostat housing.

That said, if your gauge says 120F and your bike is overfuelling and your oil looks bad, then yeah something is not performing as intended; please do reach out to us.