The Strange Case of the Yamaha Seca Corn Popper

After hearing the corn popping in my exhaust pipe, I realized the only way to clear it was to take the muffler off.
After hearing the corn popping in my exhaust pipe, I realized the only way to clear it was to take the muffler off.

Motorcycle Tales

When you think of one of those hot air corn poppers, one with a four-cylinder double overhead cam mill attached probably doesn’t come to mind.

You tend to think of a friendly little plastic job that sits on your kitchen counter and emits the unbeatable aroma of popcorn poofing-up to perfection with no grease or oil.

Quite by accident, on a recent trip to the U.P. of Michigan, I realized I had one of the DOHC types.

After hearing the corn popping in my exhaust pipe, I realized the only way to clear it was to take the muffler off.
After hearing the corn popping in my exhaust pipe, I realized the only way to clear it was to take the muffler off.

I keep two of my old motorcycles up there and got them out to take a fall color ride on a surprisingly balmy early autumn afternoon. One of them is a 1981 Yamaha Seca XJ750RH.

As the original four-into-two exhaust system has been replaced with a Vance & Hines four-into-one pipe, the bike has assumed a pretty authoritative sound. On the afternoon in question, the bike started immediately but had a decidedly muted tone. As I blipped the throttle, after a minute or two, what appeared to be a jet of white steam was issuing from the exhaust outlet. Strange—very strange.

I began to suspect that the old scourge of a rodent nest in the pipe could be the problem. Winter is coming and in the north land and nobody knows it better than the wildlife.

The little varmint had packed the pipe full of corn from about five inches from the end to a couple inches into the headers.
The little varmint had packed the pipe full of corn from about five inches from the end to a couple inches into the headers.

Rather than immediately shut down, I thought if I gave it a little more gas, whatever nesting materials or whatnot the little buggers could have hauled into the pipe would be burned up and blasted out. After another minute or so, it became apparent that was not to be. So, after several attempts at the “burn and blast” solution, I shut it down and decided to try to see what might be in there.

Then, more strangeness. In the quiet of the Northwoods, I heard a muffled “boomph!” Then another, and several more “boomphs” in succession. How odd. The sounds seemed to be coming from somewhere nearby—like in my bike.

I got a flashlight and peered down the outlet of the pipe, and, sure ‘nuff—there was something down there, but I couldn’t really tell what.

So, I got a long stiff wire with a small hook on the end and began probing the depths of the pipe and managed to pull some of the stuff out. It turned out to be corn—the kind some folks use to encourage deer to hang around near their blind. Now, that is usually plain old field corn, and I never really thought about it, but it turns out, popcorn isn’t the only kind of corn that will pop if given enough heat—field corn will, too. And it was popping—and expanding—way down there in my exhaust system!

With its exhaust system unclogged and reassembled, the old Yamaha took me to Sunday Lake in Wakefield, MI. It is a great autumn motorcycle destination—or all summer long.
With its exhaust system unclogged and reassembled, the old Yamaha took me to Sunday Lake in Wakefield, MI. It is a great autumn motorcycle destination—or all summer long.

I realized that my burn and blast approach to clearing the obstruction had probably made things much worse, with the corn kernels tripling in size as they popped. Numerous attempts to drive the long wire through the obstruction to bust it up and clear it out proved the pipe was packed all the way down to the headers and beyond. I soon realized the only way to get the thing cleared was to take the muffler section off entirely.

I don’t know how much corn was in the pipe and header altogether; let’s just say fistfuls that amounted to a winter’s worth of good eatin’ for some industrious rodent. Truth be told, I still feel a little guilty for undoing the little feller’s summer of work hauling all that corn in there a mouthful at a time. He’ll have to go some to replace it before the snow flies, but he’ll have to find a different store room; I made a wood dowel plug for the outlet that he won’t be able to pull out.

Indianhead Mountain at Big Snow resort has this magnificent view north toward Lake Superior.
Indianhead Mountain at Big Snow resort has this magnificent view north toward Lake Superior.

With the pipe put back together, I made a little fall color ride to Indianhead Mountain at Big Snow Resort with its stunning view north from the summit and to Sunday Lake, both at Wakefield, Mich.

The changing of the seasons is a beautiful time up in the Northwoods, but you have to watch out for those corn packin’ varmints.