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This is originally from an email to a friend asking my opinion on motorcycle GPS options…

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In a big push to get the Pelican luggage attached to the bike before a trip to the Delaware Water Gap, I spent a lot of evenings and a couple weekends frantically trying to finish a workable design and get it prototyped.  As mentioned in the last post, I had what seemed like a workable puck design all sorted out, but the more complex latching/locking component still needed work.

I wasn’t sure at first if I was going to design it such that the Givi rack needed to be modified, perhaps with a different catch component.  In the end, I decided the more interesting challenge was to make it work with an unmodified rack, and also felt this would make a better end product.  So, I set off with this goal, and spent a couple of days trying out different design ideas on paper, and eventually refined them into CAD models.

The approach I ended up with would require a significant hole to be cut in the Pelican cases, for the end of the catch to poke into the case.  I could have avoided this, at the cost of making the bike wider when it had luggage mounted.  I deemed this an acceptable tradeoff, and knew I could solve the case breech with some clever gasketing and another machined plastic part.  I ran out of time to complete this part before the trip, but with some mis-use of thick plastic sheeting and gaffer tape, I came up with a quick fix that worked fine for the trip.

Working out a locking mechanism was also a bit of a challenge, but in the end I came up with an acceptable approach which seems like it will be secure enough for the application.  Unfortunately, I also ran out of time to actually fabricate the locking mechanisms before the trip I had planned, so I used a cable lock and padlocks to keep the cases secure to the bike.  In the near future I will complete the locking mechanism.

Above is a video showing the simple process for attaching and removing the case.  Ultimately, the design ended up being quite solid, and survived an 800 mile shakedown trip with no issues to speak of at all, aside from the inconvenience of not being able to lock them up easily.  It’s not out of the question to improve the strength of the setup even further in the future with a metal backer plate, to be installed inside of the Pelican case.  It’s fairly rigid as it is, using just the durable plastic of the case as support, but it may not survive multiple drops of the bike onto the cases.

The cramped cockpit and limited cargo options of my Kawasaki Ninja EX500 weren’t going to suit my long-term desires for a motorcycle, and I had long been bitten a bit by the adventure touring bug after watching the Long Way Round/Long Way Down series a few years ago.  Having champagne tastes and more of a reputable microbrew budget, I decided to try to find myself a relatively new low-mileage Suzuki V-Strom.  After a couple of weeks of scouring Craigslist, I turned up a nice looking bike in Vermont, and the rest, as they say, is history.

Reeling a bit from the purchase in these tighter economic times, I was not really in a position to go out and plunk down big bucks for the highly regarded Touratech Zega setup, as featured on Ewan and Charley’s bikes in both Long Way series.  I needed a more economical approach that would result in a functional and high quality luggage solution, and look acceptably nice on the bike.  Some DIY was not a problem, and in fact welcome.

I figured my best bet for getting the project done in a reasonable time frame was to start with some off-the-shelf available side racks for the bike.  Sure, I could learn to weld (and in fact, have equipment on loan from my friend Dave to start that process), but there was no way I would be able to produce a nice set of racks in a couple of weeks, which is a deadline based around a trip that I’ve been invited to join.

So, after looking at the options for side racks for the V-Strom, it seemed the least expensive bet was the Givi tubular side racks.  The runner up was the common SW Motech side racks with quick-removal system, but they are more costly and less secure (without modifying them to be more permanent anyway).  Other options were available, but most were specific to particular brands of side cases.

With the side racks decided, choosing cases was next.  Pelican cases are a popular choice for DIYers – they’re waterproof, warranted for life, durable as heck, and have their own sort of industrial/military charm to them that carries a certain robust function-over-form look.  In fact, a company called Caribou Cases makes a commercially available case system out of Pelican cases, and adds some nice features like case locks and quick release brackets.   Twisted Throttle also offers their own spin on the idea with their Storm case system.  Many people have done DIY systems, either mounting them to the side racks semi-permanently (not ideal in my opinion), using some off-the-shelf “pucks” which allow the case to be released from the rack only by opening the case first, or building somewhat crude DIY quick release systems.

After what seemed like days of deliberation, I finally decided on the Pelican 1550 cases, providing around 34 liters of storage each.  I planned to design and fabricate my own elegant locking quick release system that would mate to the Givi side racks.  In the short term I plan to use padlocks to lock them shut, but long term the goal is to add my own case lock mechanisms to the cases, a la Caribou.

After spending an evening sketching out ideas, and another evening finishing up some preliminary CAD drawings, I have the first part of the design modeled.  The idea is to create a mate to the two protruding pegs that are located on the bottom of the Givi racks.  Externally, each mating puck will consist of a durable plastic component (shown in green in the CAD) with a machined channel that captures the peg on the Givi rack.  It will be backed up by an aluminum disc with a counterbored hole to give the plastic component more strength to dissuade it from splaying at the open end.  The whole puck assembly will bolt through the back side of Pelican cases, with the plastic part facing outward.  Inside of the Pelican case, the bolts will be backed up either with fender washers or a similarly shaped metal disc with the matching three holes.  I am undecided on whether I feel threading into the plastic peg receiver will be sufficiently strong or if I will need to countersink the bolts and keep the heads on the outside of the case, with the nuts inside.

This handles the concept for the two bottom points of each case, with two of these peg receiver assemblies to be installed in appropriate places on the case.  The trickier part is a durable locking mechanism.  I have some ideas sketched on paper that I believe will work, but I need more design time before I can present them.  I am fairly certain I will be removing the latch component from the Givi racks (the protruding triangular bit on the top rung of the rack) and designing my own component to replace it.

My little EX500 bike is a bit cramped for me.  One of the worst problems is that my wrists, especially my throttle wrist, have been going numb even after only short rides.  I thought it would be worth trying some handlebar risers to bring the grips a bit closer to me, and improve the angle between my wrist and the bar.  There are some commercially available risers for the EX, but given that I have a CNC machine and a penchant for making things more difficult than they need to be, I thought I’d try making my own.

The basic idea of the commercial risers seemed sane enough, so I figured I’d just copy them.  The only real trick was measuring up one of the flanges on the handlebar, which I did a couple of weeks ago on a cool and rainy Saturday morning.  With a bit of guesswork and a few 1:1 printouts, I was able to zero in on a close match to the OEM handlebar flange, and I knew I was on my way.  After staring at the CAD for a short while, I determined I would go one step further and do a bit of a custom twist, and add tabs to hold a small “dashboard” for a GPS mount or other possibly for accessories like a Powerlet plug.

I ordered a couple of large chunks of 2024 aluminum bar stock (1.5″ x 3.5″ x 10″) off of eBay for a pretty good price, tracked down the longer M8-1.25mm bolts I would need to replace the stock bolts in the handlebars (I used 50mm length), and picked up a new 3/8″ 3 flute endmill with a 1.5″ cut length so I could actually mill the thick stock.  With all of the materials in hand, and the prospect of a bunch of motorcycling coming up this weekend, I figured I’d push to try to get the risers fabricated in an evening, and was successful, barring a couple of recoverable hiccups.

This project is the first when I really made use of the new Tormach tooling system that I bought with all of my leftover nickels and dimes a couple months ago.  I didn’t do anything super fancy, but the main part of the machining did have one tool change.  Had I done all of the drilling by CNC instead of manually, I would have done several more tool changes.  The major lesson learned is that the drawbar really needs to be tight, much tighter than is typically required for a normal R8 collet.  This is the second instance where I’ve had the tool get loose in the Tormach collet and dive into the workpiece.  Thankfully it was during contouring, and I was able to recover, though I did lose precision on the part because I had to re-zero it.  The corollary lesson is that I need to more diligently create and use a zero touchoff point for X and Y so in case of having to re-zero I can get closer than I did this time.

The third major area is improving my fixturing techniques.  I lose some amount of precision when I bolted the workpiece down to the fixture plate that I made.  I simply was not able to get it to line up with the original drill positions as closely as I wanted.  I think the cheap Chinese 5/16″ bolts I was using were all bent and forcing the workpiece this way and that, not allowing me to properly align it with the soft hammer and dial indicator.

All in all, it was a low precision part so none of the mistakes/problems really mattered.  And, as you can see by the photos, it fit perfectly fine despite the troubles.  In fact, it was one of the easiest fitups I’ve done – no problems whatsoever mounting the risers on the motorcycle this morning.

Next up is to measure and design the crossbar “dashboard” plate which will mount between the two tabs that protrude.  There will be some careful balancing of where that plate falls, to make sure I still have enough room for the ignition key.

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I recently got a motorcycle, and since I have a CNC milling machine, there’s plenty of excuse to try my hand at making some farkles for the bike.  My girlfriend also happens to ride a V-Strom DL-650, and needed a kickstand plate so her side stand wouldn’t sink into the dirt where she parks her moto.

Add a little bit of CAD/CAM time, a bad ‘Strom pun, and a couple hours with the CNC machine, and you get what you see here.

I have a few other projects in the works for my motorcycle, mostly in the name of making it more comfortable and safer to ride.  I’m a tall guy, and my little EX500 is a bit cramped for me.  So, I’m working on a design for some handlebar risers, and also some mirror extensions so I don’t have to keep ducking my elbows in to see who is behind me.  More on that as the projects evolve.  The materials are on order and CAD/CAM work is underway…