Project 2-4: Getting a 2-Stroke Motor in a 4-Stroke Frame, Part 3

Mar. 16, 2011 By Rick Sieman
In part two of our project, we got the motor installed in the chassis but didn't have it lined up perfectly from side to side. In other words, we had the motor mounts in and the bolts installed, but we did not have the spacers in place to finalize the engine placement.

An American 1/2-inch bolt was placed in position for the rear motor mount.

Our last motor mount was the big rear unit, and we drilled out the existing motor hole to 1/2-inch American. Then, after some serious scrounging around, we found a long grade 1/2-inch American bolt that would serve as the prime anchoring device for our install.

As you can see, the bolt runs the entire width of the frame and goes into both motor mount tabs.

To make sure that things got lined up properly, we installed the swingarm and the rear wheel, complete with the sprocket. And while we were at it, the forks were bolted in place.

Read up on the previous Project 2-4 stories:

Part 2

Part 1

So follow along with us now and see how things develop.

Here's another view of the rear main motor mount bolt installed. As you can see, we already have some spacers roughly in place for the side-to-side measurements.

Some spacers for the swingarm were fabricated by simply turning down some old bushings that we had laying around.

The swingarm assembly was then bolted into place.

 Here’s another view of the swingarm pivot bolt being installed in the frame.

While we were at it, the entire fork assembly was being readied for installation.

At this point, the forks were installed, but the top triple clamp and the handlebars were not.

Here's a little trick that might come in handy. With just one person trying to install forks in a steering head, it's quite difficult to do. With the use of a few tiedowns through the axle and looped over the frame, we were able to get the forks position properly.

Just for the heck of it, we popped the front fender into place.

Then to keep things rolling, the gas tank, shrouds, and the aluminum subframe got bolted home.

What the heck, as long as we were this far along in the project, the rear fender was popped into place.

Then after sliding the motor from side to side and making sure the alignment was correct with the rear sprocket, we cut some spacers to size and installed the motor in correctly.

It was then that we noticed that the gas tank was almost touching the spark plug when it was installed. We couldn't even put the spark plug cap in place. This was a problem that we’d have to rectify later on.

At first, we thought the coil would mount properly on the mainframe in the position shown here. Wrong! Whenever the forks were turned to the hard left, they would hit the coil.

On the other side of the frame, we mounted the CDI.

Mounting it was simple, once we fabricated a small bracket. Existing frame holds for use for the mounting.

We relocated the coil a bit further down on the frame, and had to fabricate another small bracket, but existing frame holes were used. Most of our time was spent hunting for the right bolts.

That's it for part three. Stay tuned for the carb installation, airbox set up, and the all-important expansion chamber.

Read up on the previous Project 2-4 stories:

Part 2

Part 1 Newsletter
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