CT70 / Honda Trail
The Honda CT70 is a 20th Century classic. The bike debuted in Japan as a mini motorcycle for children in the early 1960's. Originally released as the Honda ST series in Japan, it also went by the name Honda Dax. Dax is short for Dachshund, which in the case of this bike, it's a reference to the shape of the Dax bike looking similar to the sausage dog, in particular, the long and bench-like style seat on the Honda ST series.
It wasn't until 1969 that Honda would export the bike to the US and Canada as the CT "70" series, however, they quickly became known as the Trail 70 Honda series, mostly because of their off-road handling. That and the fact that not all states class these as road legal. Some do, but not all. They're almost always sold as "Trail 70" bikes.
The CT in the series name stands for Cub Trail, a reference that it was designed for kids to ride, but given the sturdy build and easily handling, adults have and still do have a great time on these easy riders.
Since the original release, the most common was the automatic transmission. Only a couple of models were released with a manual clutch and those were the 1970 release of the CT70H-100001 and the later model in 1972, the CT70H-2000001. Following that, every other model uses a 3-speed automatic clutch due to its popularity with kids and their parents. The releases continued nearly every year up until Honda stopped production in 1994.
Since Honda’s patent expired in 1998, a number of replica Trail 70 mini bikes are on the market. None quite match the bespoke feel of riding an authentic classic of the t-bone frame made with pressed-steel, equipped with fatter than average tires, foldable handle bars, and foldable footpegs making it an ideal off-road trail bike as it can be folded down and tossed in a car trunk to ride on trails anywhere. No trailer needed.
The build was sturdy and would take to any trail, hence the nickname - mini trail bike, rather than the intended Cub Trail. Adults wanted in on the action too!
The engine used on the CT70 bikes is the same as the Honda CL70 series, which also features in the ATC70 and TRX70 vintage bikes. In modern bikes, the same style of riding is seen in the Honda Z series, most notably, the street-legal Honda Z50 although that has a 49cc engine. CT70 bikes have a 72cc engine.
The materials used on the Honda 70 trail bike were extremely lightweight. Even super soaked, the wet weight of a CT70 classic would still be under 150 lbs. Dry, it’s closer to 140 lbs.
There's no doubt, for its time, the CT series, or as it's better known, the Honda Trail 70 series is one of the best mini trail bikes and remains a classic today.
The Honda CT70 was available in a range of colors up until 1980. The last vintage Honda CT70 was the bright yellow model with the serial number: CT70 5000001, and that was released in 1979. Prior to that was the '78 release of the CT70 2700005, which is the all-black frame. The CT70-2600008 was the 1977 release which is the bright orange Honda mini trail bike. The 1980 release (model number: CT70-5100001) was in Tahitian Red and it remained that color on every release after that.
What's not clear is whether the subsequent releases from 1981 were actually made by Honda or if they were licensed to another manufacturer in the USA and Canada, rather than be made in Japan then shipped. Honda's production numbers only include the models sold with the serial number starting with CT. Since 1981, the serial numbers changed for the Honda Trail 70 bikes sold in the US and Canada. Those start with JH2D and that change happened in 1981 with the last production runs being the serial number JH2DB011:PK200001 and very last was the JH2DB010:RK300001 in 1994.
Given the sturdiness of the t-tube frame, there aren't many parts that continually need replacing. Probably the most common repair is switching out the spark plug. The tell-tale sign for when this needs doing is when you try to turn the key in the ignition switch and the engine won't fire up.
Given the age of the CT70 mini trail bikes, rust can be an issue on the frames, in particular the fuel tank. One of the most common questions for mechanics fixing up a Honda CT70 is whether to repair or replace the tank. Replacement tanks are still made by Honda in the US and in Canada, and there's also various brands that make similar tanks compatible with Honda CT70 bikes. Some are plastic, others are metal. If you're using a non-branded tank that's compatible with the CT70, the Z50 fuel cap is compatible, as is the fuel cap for the ATC70.
One thing's that is for sure is that a well looked after CT70 will last years, probably decades. Assuming you replace like-for-like, as in stick with metal parts and away from cheaper plastic replacement parts, you'll get plenty of fun riding on a Honda trail bike, whichever year it was made.
Whether you're refurbishing a CT70 or replacing worn-out parts, you'll find what you need at TBParts.com.