Restoration of Old Vehicle x Yamaha Trail DT1☆Final installment: "Full Restoration of Old Vehicle" is finally completed with modern technology while looking stock!

YAMAHA Trail 250 DT-1 1969 Vol.17

The Yamaha 250 DT1 has been almost fully restored, although the engine has not been completely disassembled. However, this is an old car. It is no wonder that anything can happen at any time. When the crank noise starts to come out, the lower back of the engine will be disassembled and overhauled. For the time being, this is the last part of the restoration.

Lift-up stand for VMX that is useful for maintenance

Aichi-based Dirt Freak sells a lift stand for VMX (vintage motocross) machines. Slip it under the engine and step on the arm to stand up!

The Dirt Freak lift-up stand can be used for all old car trailers. If you use it for modern motocrossers, it will raise too high, but since it's specifically for VMX, the lift is modest.

Aluminum ICBM® cylinder improves heat dissipation at once.

The engine itself underwent only an overhaul above the waist and a paint finish on the engine cover. The cylinders, which are the focus of attention, are ICBM® spec with aluminum sleeves (fabricated by iB Inoue Boring). A "pillar" was added to the intake and exhaust ports to prevent the pistons from swiveling and the piston rings from popping out into the ports.

The entire bike looks beautiful with the accumulation of detailing and finishing touches.

The muffler was Cerakote coated by Powder Coating Kato. After the old paint was stripped off with Sambra, "It's hard to find a muffler in such good condition! said craftsman Kato.

Synthetic zoil for two-stroke engines is used to care for engine condition. The "red oil" that even veteran riders appreciate adds to the atmosphere.

A small new tank cap with a tuning fork symbol was found in a box of restoration parts that was entrusted to us. Apparently small new tank caps with tuning fork marks were available for new parts until recently!!!

The rear shock was disassembled and finished from a genuine DT1 part. The damper body was disassembled, cleaned inside, and assembled with #10 oil for suspension. So far it is working without any oil leaks.

We received the stretched front and rear spoke wheels, but the "centering runout" was all redone because the center circle and runout from side to side were all different. Dunlop tires are now modernized with size indications.

The stock steel driven sprocket with six large holes, a characteristic of the early DT1. This is an extremely high quality used part with little wear and tear, and has been re-Uni-chrome plated.

Floating mounts for the rear brake panel were designed without regard to cost. This is a genuine manufacturer's specification and is a feature of the early DT1 models. The swingarm of the early series had a square cross section.

The export version was finished with single seat style parts, but the domestic version had a double seat with a longer seat surface. Even with blinkers, the early seat rails were so shallowly bent that fingers could not fit in the gap between them and the fenders.

The first series of DT1s featured a tachometer diameter that was one size smaller than the speedometer. The rubber protector that attaches to the meter ring is also a rare part.

The seat is based on an export-spec single seat and is finished with reupholstered upholstery. Although shorter than a double seat, it can accommodate two small riders.

The 250DT1 with a round reflector integrated into the tail lamp; later DT250 models changed the specifications to a rectangular, less tasteless tail lamp design.

The 1969 model with indicator has the same switch design as the one for the YDS3 road sport model, but with a longer harness cable. The turn signal switching knob also had a nice clicky feel.

I'll leave it to a local motorcycle buddy who loves his Yamaha 250DT-1!

I'm leaving the 250DT1 in the hands of my neighborhood uncle bike buddy who "lives for trail bikes" I think a smaller rider would be better suited to the DT1 than a larger build. If you hear a crank noise, take it apart.

I had always wanted to take on the challenge of fully restoring a VMX machine. I had always specialized in road models, so there were many things that were new to me.

I had a neighbor who was a DT1 enthusiast and had a lot of spare parts and parts-retrieved vehicles. It is very hard to buy a wrecked bike, gather parts from scratch, and complete a complete bike. I myself have restored two Kawasaki Triple 500H1 Mach IIIs, a 750H2, and a CB750 in the past, but the prices of parts and base vehicles have changed dramatically in recent years compared to when I was restoring them (2 to 30 years ago)! In the old days, restoration of old cars was a hobby for those who liked to tinker with motorcycles and had no money.

Today, however, full restoration has become a "rich man's hobby. Not only popular models, but also epochal models in the old car category continue to be overpriced across the board. Consulting with friends who owned the base vehicle and its parts, we were able to start this VMX full restoration project.

Epochal models in the old car trail category include the Yamaha 250 DT1, Suzuki TS250 Hustler, Kawasaki 250TR Bison, and for Honda, the MT250 Elsinore. Sibling models with different displacements can also be considered such epochal models. My motorcycle friend is a true Yamaha fan, and he told me that he had a 1969 DT1 model that he had acquired for parts and that he might be able to find parts to assemble one bike if he looked hard enough. He said, "I might be able to find some parts to assemble one of them. The DT1 and parts were kept from the friend and fully restored.

Since this is a serialization of the full restoration work, the project will end when the machine is completed. However, if there is any trouble, or if the crankshaft starts making noise after running, we may one day take down the engine and overhaul the crankshaft from complete disassembly. ......? I am also thinking about it. Of course, I would like to enjoy the work progress with the same "commitment" as before. Thank you very much for your long time patience.