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Hello out there! I’d like to apologize for not publishing journal entries more often, but as we are still in Minnesota (for at least another month) there isn’t a whole lot to write about except for our building process. Which some people may find interesting..

Since our last entry, we’ve gotten my bike to 90-percent completion. While it looked like it was in better shape on the outside, the inside of the engine was another story. Many of the components seemed much more well worn than Ehren’s engine did, along with some of the frame bolts (which were half-eaten due to apparent battery boilover at some point in the bike’s life). Luckily we had planned for some of this with Ehren’s rebuild and had several extra components on standby (and were able to quickly find the parts that were unplanned repairs in town!). All that’s left to do is some minor electrical, installation of the new clutch pack, and its first startup.

Here we have attached the crash bars and pannier racks to ensure a good fit (and to show off that awesome orange color—apparently I have some lingering KTM hangup).

As we are sort of socked in for the winter (snow is gently falling into a well-established white sea of the stuff as I type this) there hasn’t been a whole lot of opportunity to test our bikes and trailer. But what testing we were able to complete shortly after Thanksgiving was incredibly informative as to our next steps. Our trailer suspension has undergone an entire rehaul as we have gone from our one-wheel swingarm concept to an innovative two-wheel design utilizing a reverse swingarm. Two wheels means that our front swingarm mount has had to change as well, and thanks to Ehren’s childhood cache of Lego® we were able to hash out a pretty slick design that gives us the mobility and stability we want.

Yeah, but Lego® is child’s play! How could that translate into actuality!? Surely toy geometry is different than steel geometry..

Hey, it worked! The reasoning behind the reverse swingarm idea is this: we had already built a complete trailer box as we were planning on one wheel from the start. Due to the final heft and weight of the beast (which exagerrated existing weaknesses in the heim joints and shock mount and made it truly scary to ride—you couldn’t ride it and keep the handlebars straight) that idea didn’t work as well as we’d hoped. We didn’t want to cut into the storage area of the trailer to put in a straight axle as it would severely weaken its construction and we still wanted to maintain that 8-11 inches of travel we had in the one-wheel concept, which left out the use of stubby torsion axles which would have given us 2-3 inches at most.

Our first attempt at redesign was the quickest and least work-intensive option, which was simply to use the existing one-wheel swingarm as a two-wheel swingarm, mounting the wheels outside the arms instead of just the single wheel in the middle. After the 15 minutes it took to rig that up we could immediately see big issues, namely the tippiness of the trailer during slow-speed turns. The axle was so far back from the pivot point that the trailer just wanted to dive into the ground.

So we had lunch and discussed other options for about an hour. Ehren had an idea for an elaborate three-piece rocker arm setup which I didn’t care for due to too many moving parts. I talked about a drop-axle design which could work but would have left us with very little ground clearance. We then looked again at the rocker arm setup, both adamant that a simpler solution existed. I showed Ehren a terrible drawing I did of his idea with two pieces (mainly because I didn’t understand where the third piece would come in and wanted an explanation) and he took off from there—the reverse swingarm concept was born!

The basic idea for the redesign is to take a U-shaped arm with a V-shaped bracket mounted on the inside (between the arm and trailer so it looks sort of like a W). The shock would mount from the top of the trailer to that V bracket attached to the U arm. Then we would utilize the existing lower swingarm mount but push the pivot point further away from the trailer, where it would mount to the U arm independently of the V bracket.

Not too shabby. Actually it kind of is at the moment, due to the weld burns on the blue paint. Our leftover paint froze and is no longer viable so we will have to come up with another solution to cover up our blemishes.

In essence, it’s a swingarm with its arms facing forward instead of backwards.

Ehren giving us his best motorcycle impression.

We will be able to give it a test run when we go to Florida at the end of the month to visit Ehren’s grandpa. Ehren’s dad suggested we accompany him when he drives down and offered to trailer our bikes and moto trailer so we could test them on dry roads. So it’s this road test that will decide when we will ultimately be able to leave on our trip! Yeehoo!!

—Britt

 
 

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