Author Topic: Bestem Topbox 2012 Installation ( ST1100 ) *  (Read 10081 times)

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Bestem Topbox 2012 Installation ( ST1100 ) *
« on: August 03, 2011, 05:10:14 PM »
Original article can be viewed here:

Submitted by Bob Shwery, STOC #8058


Bestem Topbox 2012 Installation ( ST1100 )

I bought the Bestem 2012 42 liter tbox on ebay from, AKA I picked this particular tbox because it has a gloss black top that I felt was a better match for my mostly gloss black ST1100. I also gave a lot of consideration to storage capacity. On my former bike I had a Givi e52 (52 liters), and on my Gold Wing before that I had a trunk that was 56+ liters. Well, I don't have a Gold Wing now and I really didn't want to spend a weeks worth of wages (or more) to buy a top box. I also realized that I didn't need a really gargantuan top box. So I overdosed on finding and looking at dozens of pictures of the ST1100 with the Bestem tbox installed. Most were of the larger 46 liter Bestem 929 on the ST1100, and most of the Bestem 2012 were on the ST1300, but I did find a few (very few) of my model bike with the 2012 tbox. I wasn't sure if I liked the larger model 929 with the flat black finish. It didn't really match the bike as well as the 2012. Besides having a gloss finish I also wanted to be sure the 2012 wasn't too small for my needs. I decided to let one particular item that I often carry home from shopping be a deciding factor whether to go for the 2012 or get the bigger 929. The 24 pack cans of Diet Coke is a common large size and shape of box that would tell me volumes about what would fit in the top case. Most riders compare how many helmets will fit or how a single helmet fits inside, but helmets are so many different sizes and shapes it was difficult to determine what that was showing me. The box of Diet Coke is one item I was familiar with that is universal and unchanging. I found that no one could tell me if that box would fit inside. They kept telling me the outer dimensions or telling of other things they put in the tbox, but I wasn't familiar with those other things. All the tboxes are rounded, so the outer dimensions show nothing about how a large rectangular item with squared corners will actually fit inside. I guess fitting nine 2 liter bottles of Coke in the 2012 (what one helpful person told me) was close enough to want to take a chance so I ordered the 2012.

Well, here it is with that 24 pack case of Diet Coke fitting inside just fine, with a little bit of room on top and around it for small stuff.  

The following is my install procedure for the Bestem 2012 on the ST1100.

  • No holes put in the bike if possible.
  • Minimal modification to tbox mounting hardware.
  • Provide for set back of tbox for passenger comfort.

One used 8.5 x 11 polypropylene cutting board. Was white, but I painted it black.
4 m8 x 1.25 x 60mm hex socket cap bolts to replace the stock cap bolts.
4 3/8 id x 1/2 od x 1 bronze spacers (actually bearings but they work well for this)
4 5/16 id fender washers.
4 m8 nylon insert lock nuts.
1 m8 x 40mm bolt with a low profile plastic knob. I liked the knob and felt this would not scratch items in the tbox.
1 m8 wing nut.
1 small Rclip cotter pin (already had this on hand).
6 small 5/16 id washer (already had these on hand).
4 m8 washers provided with the tbox.
2 luggage rack brackets provided with the tbox.
1 base plate provided with the tbox.
4 m8 x 25mm stock hex socket cap bolts from the rear mounting of the hand grips.

Here are the parts all laid out. Hardware in the upper left. Cutting board and brackets in the upper right.
Bestem base plate in the lower left. Paper template in the lower right.

The goals are realized by using a polypropylene cutting board as an intermediate adapter plate. You may choose to use an aluminum plate instead but I am cheap and attempt to use things I already have on hand if possible. I did buy a new cutting board for my wife so I could take her existing one. The old cutting board was thicker than the new ones anyway so that was preferred. I did use the stock bolts from the bike, but not in their usual location as indicated below. I also used the luggage rack brackets and washers that Bestem provided as indicated below. A few materials I found in my scrap box. The other materials were purchased at True Value since they have the biggest selection of metric fasteners, or Lowe's since they were close and I realized the need for additional items as I was figuring this out.

I wanted to use hex socket cap bolts to minimize what tools I needed to install or remove the whole assembly. The stock cap bolts could be used with the nylon insert nuts to mount the base plate to the cutting board. I used the rack brackets included with the tbox to reinforce and strengthen the cutting board and also the washers that came with the tbox. I installed each bracket front to back rather than side to side so they would better support the cutting board where it hung out the back. I also found I could run all the bolts through the brackets under the cutting board to tie it all together and make for a much stronger support. I did have to drill two extra holes in the brackets to do this. This is the only modification to the tbox mounting system other than drilling a single hole in the bottom of the tbox and base plate for the plastic knob security bolt.

Prep step 1: I had my wife sit on the back seat so I could determine how far back to mount the tbox for her comfort. I also made sure I could remove the seat. I was thinking I may be elongating two forward base plate mounting holes to bolt directly to the rear bike mounting points but found the tbox needed to be slid back about an inch from that. I marked the bolt pattern for the rear hand grip bolts on a paper template and then cut the template to include enough size for the tbox base plate mounting. I lined up the base plate over the template and marked the mounting holes, being careful to get it straight on the template and set back per my earlier estimate. This was made easier since I had noted that the front of the base plate needed to line up just at the forward tail mounting bolts.

Prep step 2:
Using the paper template I marked the holes to be drilled on the cutting board. I marked and cut off the cutting board handle so the board would be the size and shape I needed. I rounded the corners using a large washer as a guide that matched the other corners. I didn't worry any more than that about finishing the cut edge since the board would be almost totally covered by the base plate when installed.

Prep step 3: I drilled all the holes as marked in the cutting board using a 5/16 bit. Throughout this process and after each marking or drilling I double checked to be certain the holes lined up with the bolt positions as they should. The size of the holes I drilled are just enough for the bolts to fit through so they had to line up exactly. If not I would have to enlarge the holes a bit and I really don't like doing that even though it wouldn't be any problem if not done very much.

Prep step 4: I used two of the holes just drilled in the cutting board to temporarily bolt the brackets on and then marked the additional holes needed in the brackets. Then I drilled those with the 5/16 bit. I removed the brackets to drill these holes (easier for me) but you may choose to drill them with the bracket still bolted to the cutting board.

In this photo are the cutting board and brackets with all the holes drilled and ready for a test fitting. I haven't painted or cut the notch for the security bolt yet.
Note: I didn't drill any holes for the security bolt until after everything else was mounted and verified to fit right.

All of this prep work took longer than the rest of this project, as is expected. My wife is always telling me how it seems that I take a very long time to get started with nothing to show for it. But that's just the way it is. Do the prep work right and when you start putting it all together it almost falls together by itself.

Then the fun began... assembling it all.

Here is a test fit of all the parts showing how the brackets, cutting board and base plate fit together. Near the center of the base plate you can see the hole drilled for the security bolt. This was actually drilled after I test fitted the whole assembly to the bike and found what I felt was the best location for it. You can also see the notch I cut in the cutting board to make room for the security bolt wing nut and cotter pin.

Assembly step 1: I placed the four bronze spacers in the aft hand grip mounting holes. The four 60 mm cap bolts with a fender washer were then pushed through the cutting board holes drilled for them. The fender washers may be a bit overkill but I wanted to spread the load of tightening the bolts as much as possible over the plastic cutting board. I then put the brackets over the bolts and set it on the tail of the bike with the bolts through the spacers. I had to push or pull the grips a bit to get each bolt started in the threads and then I tightened the bolts. I ended up with about two threads at the ends of the bolts exposed (inside the under seat storage space). This is about the same as the stock bolts were. I must state here that I tried using nylon spacers at first but as I tightened the bolts down the nylon spacers started compressing and and bulging in the middle. I knew they would soon split and become worthless. So I went with the bronze spacers. This completed the install of the adapter plate (cutting board) to the bike.

Here is how it looked after this step.

Assembly step 2: I placed a small 5/16 id washer on top the cutting board at each hole for the base plate. Then I set the base plate on top lining up the holes and pushed the four stock cap bolts through the holes in the base plate, washers, cutting board and brackets. I needed the washers between the base plate and cutting board because the cap bolt heads mounting the cutting board to the bike are a bit tall and there needed to be something to keep two of those cap bolts from putting undue strain on the base plate that might lead to failure of the plate. I then added the washers that came with the tbox parts and the nylon insert lock nuts and tightened these. Again, I ended up with about two threads exposed beyond the lock nuts. The length of the stock bolts turned out about perfect.

In this photo you can see the washers just placed on the cutting board for spacers for the base plate. You can also see that the brackets do stick out the back a little. They are covered by the base plate when that is installed.

These two photos show the base plate mounted. You can see how it all lines up and the spacing behind the seat.


The whole thing is very solid. Using the brackets under the cutting board made that platform very stiff and strong so I don't have any fear of loading 20 lbs into the tbox if I need to. Though most of the time I don't expect to put even 10 lbs in it. There is very little flex or bounce. As far as removing the seat, there is no problem with this. There ended up being plenty of room to remove and replace the seat, even with the tbox in place.

The cutting board was white, but I didn't paint it until after I assembled everything and verified it all fit together right.

If there was not much cutting board showing then I would just leave it. I didn't care if I could see a little bit of white through the base plate holes when the tbox was off the bike.

But there ended up being at least 2 of the front of the cutting board showing very apparently, even with the tbox mounted, so I went back to Lowe's and bought a can of black Valspar spray paint for plastic. It specifically stated that it was for PVC, polypropylene, etc. so I thought I'd give it a try. Time will tell if this paint will stick.

Below you see the before and after comparison.

The security bolt I chose was not long enough to go through the tbox, base plate, adapter plate and also have enough thread left for the wing nut and cotter pin so I placed the bolt as far back in the tbox as possible and also cut a notch in the back edge of the adapter plate to allow me to spin the wing nut on and fit the cotter pin. I just cut a V notch rather than cutting a fancier U notch because it was easier and quicker, and normally wouldn't be seen.

I test fitted the security bolt and marked it for drilling the small hole for the cotter pin. You can see the result in these photos.

Here are a few more photos of the (mostly) finished project. Wiring the brake light will be another project by itself.

Side view showing that I now have a few more hook points for my bungee cords using the bronze spacers.

Here you can see what is blocked in the mirrors. The other side is about the same.

Here are a few overall views of the ST with the tbox.

Now here is an idea... not!

The only thing left now is to put the tbox on and go riding! To the store of course. That is why I bought it, isn't it? Oh, and maybe some travel and camping trips, the commute to work, :)


Original article in PDF ( 13 mb )

Just an additional note on the link above. There should be an option to download the document. I highly recommend downloading the document (save or open) to view it from your own computer. The pictures show up MUCH better and clearer and sharper this way.

Thank You again for your contribution Bob Shwery, STOC #8058


Additional comments by Bob Shwery:
The plastic cutting boards can be found at any kitchen supply, Bed Bath & Beyond, Target, Walmart, etc. Most seem to be thinner than what I would prefer so be sure to look for a sturdy thicker than average board. The aluminum plate idea is also a good one but just a tad harder to work than the plastic. I do find the brackets that came with the Bestem case are starting to bow down just a bit. Not really bad but I can see it if I sight along the bottom from behind. I am considering replacing those with aluminum square tubing but haven't decided for sure yet. I also tend to load the top case more than I probably should at times so that would be why this is happening.

Have had this T-box on the bike since I installed it almost constantly. I like the convenience of that storage and the having the extra lights on the case, which I did connect after I did this article. I also added an extra LED strip just below the light strip in the lid. The black plastic paint on the "adapter plate" has stayed in very good condition so Valspar plastic spray paint is still the pick for that. I had originally used non-stainless bolts to mount the plate to the bike but have since replaced those with stainless. Otherwise all is the same.
« Last Edit: December 15, 2012, 07:33:34 PM by Tom Melnik »