Don’t Ask: Rick Sieman Answers Your DirtBike Questions

Pick the Top Ten Worst Dirt Bikes of All Time? Wow! Where does one start? Surely not with the current crop of dirt bikes. You would be hard-pressed to find a genuine lemon among the new iron-but how far back do you go?

After all, before the dirt bike boom (circa 1970), there were a lot of clunkers being foisted off on an unsuspecting public. So, after considerable thinking (about ten minutes) I decided to limit the selection to dirt bikes that I actually tested. This meant that our starting year was 1970. And this makes a great deal of sense, in that the dirt bike boom started in the late ’60s.

WHAT MAKES A BAD BIKE?
I feel that a truly bad bike should have few-if any-redeeming values. There have been great-handling bikes with fragile engines and transmissions. There have been powerful machines with less than stellar handling-and then machines with a bit of both. The real losers, though, are those with more faults than virtues. Machines that will spit you off for no apparent reason. Or bikes that are so dull and listless that you’d rather be riding in a Buick station wagon with the windows rolled up. Then you have dirt bikes that have all the reliability of a candle in a windstorm.

FLAWED WINNERS
Throughout the years, I have fallen in love with flawed-but great-machines. Consider the Maicos of the early and mid-’70s. They required a great deal of prep, set- up and TLC, but when they were dialed in nothing else could run with them. Riders put up with a wimpy primary chain drive, reluctant clutches and bogus ignitions. Think about the CZs of that same period. Heavy. Crude. Poor shocks. But almost unbreakable.

How about the various Spanish bikes? All built from inferior materials, but they were speedy and handled like magic. Those who took the time to learn how to live with them were rewarded with stunning handling and correct powerbands. Novice riders who bought the Bultacos, Ossas and Montesas of that period ended up pulling out their hair by the handful, promptly sold the strange beasts and then bought reliable Japanese mounts.

Then we had the off-brands: Puch, DKW, AJS, KTM, Penton, Sachs, Greeves, American Eagle, Rickman, Rokon, Harley-Davidson, Steens, Bridgestone, Bronco Apache, Chaparral, Carabela, Cooper, Monark, Zundapp, Yankee and a few others that will probably come to mind later on.

ODDITIES THAT BOGGLE THE MIND!
Some truly strange things have appeared on dirt bikes. Consider the following:
• The Bridgestone Hurricane Scramblers of the late ’60s and early ’70s had a rotary shift pattern that was bizarre beyond belief! You would shift up through all six gears, then when you hit the shifter one more time it would go back to low gear. Imagine the surprise when the rider was in top gear, all tucked in and howling down a fire road, and snicked the lever one more time, only to be greeted with low gear and 11 million instant rpm!
• Rokon came out with the first automatic trans (actually, a torque converter) with the power delivered via a rubber belt. This beast also had to be started like a lawn mower; you had to pull a stupid rope. When it got hard to start, you would be sucking wind in a hurry. When that torque converter belt got wet, it would slip and smoke like a worm on a barbecue.
• Greeves found out that the kickstarter would not clear the footpeg when starting, so you had to fold up the peg by hand and hook it onto a restraining ring. Nice touch.
• Numerous Euro bikes came with paper filters. When the engine backfired, the premix would saturate the paper and it would pass about the same amount of air as a can of peaches. If you rode through water, your ride was over. Gag, puke, cough, wheeze.
• The IRZ carburetor. It came stock on Ossas and was virtually untunable. This wretched carb had two needles and two completely separate fuel circuits. Taking it apart required the patience of Job and the hands of a brain surgeon. Putting it back together was even worse. Jets were expensive and nearly impossible to find. Some fun.
• Hatta forks. They came stock on various Kawasaki “enduro” bikes. The ads billed them as “101 ways adjustable, unfortunately, none of them were correct. Mr Hatta designed landing gear for bombers during World War II and was quoted as saying, “It’s easy to make a suspension for a bomber. It only has to stroke once. A motor cycle is confusing. It has to stroke numerous times.”

REAL LOSERS!
When all things are considered, a list of duds is crystal clear. The following is a compilation of dirt bikes that meet all the requirements of what is truly bad. It’s based on frightening traits, unreliability, poor handling, mechanical woes, dumb engineering, freaky response and un-fun riding feel.

THE LIST!

We talked about the belt drive earlier, and the less said about this the better. The thing was fast and had disc brakes to slow it down. Sadly, they worked intermittently, and the master cylinder often boiled over, leaving you with a lever that came back to the grip and a corner that rushed up to meet you. Gearing down was impossible with the torque converter, which meant you free- wheeled into turns and down hills. Spooky.

The race bikes had everything changed! The stock bikes came with rigid footpegs, no horsepower to speak of, a huge overlay sprocket on the rear wheel that constantly came loose, a tank shaped like a mailbox, a saddle that felt like plywood and a strange metal hook strategically placed to rip your crotch off if you crashed. It also had stupid bars, dumb fat grips from a street bike and a suspension that had more side-to-side travel than up-and-down stroke. I called it “a re-hashed Italian street bike with no redeeming traits.” Yes, we promptly lost the H-D ads at the magazine.

It had rigid footpegs, a huge, bulbous tank, an exhaust that burned the leg, a speedo that didn’t work and various bits and pieces that were attached with pure afterthought technology. The first time I fired up our test bike, the horn fell off on the ground. After I rode the bike 100 yards, the battery fell out and the wiring loom melted. In the next 20 minutes, the plug cap came off, the air filter fell off, the muffler cracked and wedged into the rear wheel, the gas cap leaked, both fuel lines cracked, a tire went flat and the throttle stuck wide open.

The feeble engine was also horribly over-geared, the kickstarter would stick on the frame, fork seals weeped like a garden hose and the motor mounts fell out. This mount signaled the beginning of the end for CZ sales in the United States, and rightfully so.

John called it the Penton Trials, but not even Batman could have ridden it in a trials event. There was no power at all, the gearbox was spaced oddly and it wouldn’t turn without plowing the front end. So, in desperation, John renamed it the Mud Lark, a sort of all-purpose play machine. In fact, it was a no-purchase dirt bike, and will go down in history as one of the few bad business decisions ever made by savvy John Penton.

People started doing wonderful things like riding over their own legs and biffing over the bars when the things got into a high- speed wobble-you know, anything over 20 mph. Suspension on these early three-wheelers? Nothing. Zip. Nada. Zero. Just three balloon tires were there to take the impacts.

As the years passed, the ATVs got more and more powerful and they gave them forks and shocks. This let the unstable triangle wallow around, as well as defy the laws of physics when trying to turn. The rest is history. Three-wheelers are no longer being made. However, be warned! They’re still out there, wiggling and lurching around the trails and sandpits of America.

Picture this: you’re exiting a hard- packed turn in second gear and you roll the throttle on. All of a sudden, the engine lurches into the fat part of the power curve and the rear end leaps out about three feet. The chassis shudders and sends you sailing into the clear blue sky in a nice arc. Moments later, you thump into the ground, painfully, and then a microsecond after that, the Cyclone lands on top of you.

Adding to the bizarre powerband was a set of forks that went rigid on square bumps and rear shocks that faded from anything hotter than headlight glare. Many companies produced endless handling and frame modification kits. None of these things seemed to help much, but the bike cost only $995 brand new and people kept buying them, trying to make them work. They all failed, to one degree or another, to tame the Cyclone.
The legacy of the TM-400 can be summed up in an ad that appeared in a newspaper: