Tusk Drain Bolt Failure

Item: Tusk Low-Profile Magnetic Drain Plug
Part No.: 1541220001

As previously reported, I'd purchased a Tusk Low Profile Magnetic Drain Bolt for my 2016 Kawasaki KLR650. "Tusk" is a manufacturing brand name for Rocky Mountain ATV. After two oil changes during the running in, the Tusk Bolt fractured allowing oil to leak. Yes, this is just a broken bolt, but if not detected, it could have resulted in permanent damage to or the loss of my engine. The KLR does not have an oil/engine light or an oil pressure gauge. So this is rather serious!

A low profile drain plug is one of the upgrades that are considered mandatory for off-road use of the KLR650. The factory drain plug projects too low and is susceptible to becoming hung up on a rock or stump and doing catastrophic damage to the sump case. Below are photos of the factory drain bolt and the Tusk Drain Bolt as installed on my KLR650.

I installed the Tusk Low Profile Magnetic Drain Bolt during my interim oil change at 283 miles. The Bolt came with a 1 mm crush washer, but I used a fresh factory 2 mm crush washer. At 644 miles I performed the final running in oil change using the Tusk and a new factory crush washer. Each installation was performed using a torque wrench at the motorcycle's torque spec, which is 21 ft-lb. Shortly after the change, oil started to collect on the floor beneath the engine. 

The Tusk fractured in three seemingly equidistant places on the bolt cap. 

In each case, the fracture runs down the thread shaft from 2 to 4 mm. The largest can be easily seen in the photo below. 

In addition, the fractures scared the crush washer indicating to me that they may have occurred when torquing the bolt down. The second oil change crush washer is on the left and clearly shows the scars. The first oil change crush washer is on the right and appears that there may be one scar line indicating the fracture was starting, but I can not be certain of that. I did not remember seeing torque guidance on the packaging and, when I called,  Tusk Tech Support indicated that there was no specific recommended torque for their bolt. So using the Kawa factory torque of 21 ft-lb would seem to be appropriate ... and, btw, if you use a torque wrench as much as I do you know that's not a lot of torque! Certainly not enough to fracture "hardened steel" which the Tusk description claims its made out of. 

During the running in period to date, I've kept the KLR out of any gnarly off-road conditions to be able to maintain the running in RPMs (4000-5000 up to 1,000 miles). We've been on some forest roads, but there is no indication of any external damage that may have caused the fracturing. I'm ruling that totally out.

I've searched two prominent KLR Forums for other cases of this fracture and have found no cases. 

It would seem that there may be a metallurgic defect present with the product as opposed to something I did and/or need to be worried about. I've sent a thorough description and photos to Tusk Tech and Warranty Service after discussing the experience with them on the phone. Perhaps they'll come back with a reason for the failure. Irrespective, things like this will have a natural effect on one's confidence, so I'll be looking around for another option for the low profile drain plug.

UPDATE:

Experienced KLR owners who have read this post and another I put on KLR Forum recommend reducing the torque from the factory spec of 21 ft-lb to 14-16 ft-lb for ANY drain bolt on a KLR 650; not to suggest that too high of a torque caused the Tusk fracture. Rather, they note that the GEN 1 Torque Spec was 17 ft-lb, with no changes to the GEN 2 engine cases. The consensus of these owners on the Tusk bolt is metal failure likely due to overheating during manufacturing resulting in brittle metal and, ultimately, the massive fracturing.

UPDATE:

1-19-2016: I never heard back from Rocky Mountain ATV/MC on the fractured drain bolt and have moved on. Even though I now have a Ricochet bash plate, I still needed a low profile bolt because the stocker pocked through the drain plug aperture in the plate. I purchased the highly recommended Eagle Mike Low Profile Magnetic Oil Drain Plug.

The Eagle Mike has a 17 mm hex head and is about 1 mm thicker than the Tusk. Unlike the Tusk, the Eagle Mike provided torque guidance of 15 ft-lbs, which is lower than the factory spec of 21 ft-lbs and very consistent with what experienced KLR owners suggest.

Here is the Eagle Mike drain bolt under the Ricochet bash plate. It comes to right about the top of the plate and will work fine.