Sequential | Thirdwigg.com

Kickboxer Diesel

October 6, 2021 1 Comment

I have done a lot of difficult LEGO projects over the years, but this project was the hardest in a while.

You may find free instructions for this MOC at Rebrickable.com.

I often participate in Eurobricks Technic contests, and this last winter, I chose to participate in TC19 Technic Motorbike Contest as I enjoy Motorcycles, and I have built only one. This was an oportunity for me to develop some skills in a MOC that I have not done in the past. I had no idea, how much it would stretch me. From the start I committed to the following features: steering , suspension, an engine, and a transmission.

I quickly picked a motorcycle to replicate, the fantastic Kickboxer, and got to work. First I set the scale and did a rough draft of the suspension. I built a little flat 4 engine.

Then I started on the transmission. The transmission is a four speed sequential transmission that is shifted on the left of the motorcycle. I took a while to get the design to work, and then took a lot of time to get it to fit into the motorcycle. Finally, I was able to get the final solution to work. It’s dense and complicated. I encourage you to take a look at the instructions to explore it a little more.

The suspension worked until I finished much of the bike. Then it sagged, and required a complete rebuild. I was able to retain much of what I wanted even after the redesign.

The motorcycle was a build I was very happy to finish. I was frustrated multiple times in this build, so I had a high sense of accomplishment when it was done. The transmission works flawlessly. The suspension is sufficient, and the steering is a little gummy. But all in all, it’s a build I am proud of. I hope you enjoy it too.

Happy building.

Filed under Cars Tagged with 2021, Cylinder, MOC, Motorcycle, Sequential, steering, suspension, Transmission

3 Speed Sequential Transmission with Changeover

December 1, 2012 2 Comments

A couple of years ago, I was building a MAN LE with the sole intention of creating a new gearbox. The tried and true changeover with clutch gears is a great system, and works well in a lot of situations, but I had been disappointed with how it functioned in trucks. Particularly with the neutral. I could not have my trucks roll backward. There had to be a better system. There were four things I wanted to address:

First, each gear-change had to move seamlessly from one gear to the next. No neutral.

Second, it had to be easily controllable with power functions.

Third, it had to be sequential. No first to third gear shifts.

Fourth, it had to work. Every time. With no slipping.

The first goal was easy to address. I came up with a simple sequential gear box, that would move between three ratios all spaced one stud apart. In order to get to gear three, you had to go through gear two. To make sure the gears would slip into sync every time, I chose the double bevel gears as the change over gears. You can see in the video how they slide into gears pretty easily.

The second goal was the most difficult. I have stuggeled with finding a solution that would allow a motor to move from one great to the next without “overshifting.” To many designs require you to stop the motor so the gears are perfectly meshed. After looking at a design from ATRX, I had an idea. I needed to use the pulley wheels to move the gearbox in three steps. So, how could I get the pulley wheels to stop at three spots around a half a rotation. The pulley wheels would be connected via a 24z gear to a differential. Each side would have M motor, with stops for half a rotation. One motor would move a half a rotation, transmit the rotation through the differential which would turn it into a quarter rotation, moving the pulley wheels a quarter rotation as well. One motor would shift from gear 1 to gear 2, then the other motor would shift from gear 2 to gear 3. It was sequential, and it would only allow you to shift to the adjacent gear.

Finally, it worked. Every time. No missed shifts. I have made a couple of modifications to the gearing and structure to make it a little more compact and with better ratios, but if your looking for a new gear box to use for your next MOC, this might be the ticket.

See the full gallery here.

Used in my Freightliner M2, MAN LE, and ZIL 132.