Tech Tip: How to deal with a broken chaincase
Mountain Sledder | On 27, Jan 2017
Have you ever heard that sound? If you have, you won’t soon forget it. It’s a BANG! followed immediately by a loud whhhiiiizzzz and your surprised outburst as you go flying over your handlebars at mach chicken. Yep, that’s the sound of your chaincase turning into swiss cheese.
So your chaincase is broken
When that chain finally decides to hang up its gloves, it likes to go out with a bang. Sometimes it takes thousands of kilometers to reach retirement, sometimes hardly any at all as in the case here. It depends on many factors; but let’s avoid that debate for now.
The pressing concern being now that your high-horsepower rocketship to the alpine has instantly transformed into an $17,000 leather couch, you’ve gotta figure out how to get that thing back to the parking lot. There’s good news and bad news here.
You’re smart, so you’re riding with buddies. Preferably two buddies, but one will do if you’re not that popular. Because you’re going to need a tow (unless you want to dish out for a helicopter ride). And it gets better! Your buddies also came prepared! They both have a towing device, either a tow strap or at least a bit of rope. Yay for good friends!
The bad news is that not only is your sled without any semblance of self-propulsion, it’s also got no brakes, depending on the model! When your chain decided to commit harikari by blasting itself through the cover of your chaincase at the speed of light, it also self-annihilated your ability to slow your sled down.
You see, for some models of sled there is no braking mechanism on the drive axle of your sled, which is what controls the speed of the track via the machine’s drivers. The brake rotor is attached to the jackshaft, but when the chain that connects the two is gone, so is your ability to do any slowing with the brake lever. You can squeeze the hell of of that thing and it’s not going to do squat other than turn on that little red light at the back of your sled.
So when your chaincase explodes, you’re going to be awfully lucky if it happens 10m from the parking lot. More likely it happens 32km deep in “Noamsayin Canyon”. There’s probably going to be a few ups and downs on the way out.
Here’s how to deal with your broken chaincase
The nice part about towing your sled out in this case is that you don’t have to worry about removing your drive belt for once. It’s not going to slow you down or cause any damage by being in place. Also, you might as well save fuel and turn your machine off—as mentioned earlier, it’s an expensive piece of furniture at the moment.
Go ahead and attached a tow rope to the front of your sled. If you’re unsure how best to do that, check out our how to video on the topic from a few years back. Once you’re all hooked up, one pal is going to go ahead and pull you. He’s your forward power.
This is where having a second riding buddy comes in very handy. You’ll want to attach a second tow rope from the back of your sled to the front of your other buddy’s sled. That friend is your braking power.
Roped up in a series like this, you can safely be towed in situations where there are ups and downs on the way out. If you only have one riding pal with you, then you’ll have to stop and switch from the front to the back every time the terrain changes from up to down. Depending on how far you need to tow and how varied the terrain is, this could take a very long time indeed. If you’re riding alone… well, that was a poor decision in the first place, and you’re in a lot of trouble. Start walking.
Once you’ve descended the last hill and hit a road or groomed trail, you’re probably okay to unhook the rear sled and proceed with the towing sled only. But the towing sled driver needs to remain alert. Check back regularly to make sure your pal behind is doing okay. Remember that any little downhill you might encounter might be enough to cause slack in the tow line, so you’ve got to be alert and keep the line taught. Try to maintain a steady speed, and slow down well in advance of corners so you can take them at a reasonable clip.
The rider on the busted sled also has to be brave, since they really have very little control at all. If you’re feeling adventurous, you can always drag your feet to slow your sled somewhat to help keep the tow line taught as needed.
The moral of the story is: always ride with friends that are well prepared!
This story has been updated to reflect that not all models of snowmobile will have the ability to brake affected by a broken chaincase.