Step 3: Create Your Mounting Brackets

I Googled around and found where other people had made mounting brackets for hard bags or simply bolted them directly to the bike with no intermediate piece.  What I discovered was there isn't much in the way of one size fits all for this sort of thing.  There are "Universal" mounting brackets but they are only universal because they have moving pieces so that the bracket can be adjusted to fit any bike, but that doesn't mean they fit any box.  Normally it looks like people will buy a saddle bag/box specifically for the hole pattern in their box and then purchase a universal mounting bracket that adjusts to fit.  These brackets run anywhere from 100 bucks a pair for what amounts to three bars of steel with joints/bolts for adjustment to several hundred dollars for some more sophisticated technology.

We opted to take about 10 dollars worth of scrap 1/4" billet aluminum I had laying around my shop/garage and fabricate a couple of plates to act as spacers and to account for the fact that the side of my buddies motorcycle is not completely flat so there was no way the ammo can could just bolt to the side of it without being a total mess. 

First take the sheet of aluminum and hold it up next the fender of the bike and mark it for length, which should extend at least 1" from both bolts so that the pieces is at least 2" longer than the distance between to the two bolts for mounting bags.

The width of the pieces is not super critical, at least a few inches though... the wider the piece the more will be pressed against the box and the more support the box will receive, but some will have to be taken away to account for the rails on these 40mm cans anyway.  I just split the difference on the piece of scrap I had laying around and marked it up for cutting.

Once your piece is marked as shown in the photo, use a metal cutting wheel on your grinder to create the two rectangular pieces.

Once the two pieces are cut, set one aside for awhile.  Take the other and put it up against the bike again.  Using a marker trace out areas where you need to remove some metal in order to get as flat of a fit against your bike as possible given it's natural curvature or any protruding surfaces while maintaining a 1" diameter of metal around what will become the two bolt holes.  Grind away that excess metal using a bench grinder or grinding wheel on your angle grinder.

Now, to transfer a good bolt pattern onto your sheets of metal there are probably a dozen options.  We simply used a piece of blue painters tape.  First remove the bolts from the back of the motorcycle for holding bags and the fender.  Put a strip of tape on the bike covering both holes, and with the edge of the tape about as level to the ground as you can get it  by eyeballing it.  Now push in on the tape where the bolt holes are, strong enough to make a permanent inward dimple on the tape but not so hard you push a tear into it or mangle the tape in any way.  Once that is done remove the tape from the box being careful not to let it curl up or tear and transfer it to the last piece you finished grinding. Then take a center punch and place it directly in the middle of the dimple you created in the tape by pushing in on the bike, and give it one good solid tap with a hammer on a solid surface.  This small dent will help to start your drill bit precisely where you want it and mark where you want to drill... in the picture I marked the dents with a sharpie so they were visible in the picture.  Now, making sure to set your drill press to the appropriate speed for drilling this metal and thickness, drill out where you punched using a drill bit that matches the diameter of the bolts.  Once this is done make sure you can get the bolts through the metal and that they thread straight into the bike with no problem.

Now you have one piece more or less complete.  Take the other rectangle you set aside previously and clamp it tightly to the completed piece (using metal clamps, this work gets hot and will melt plastic clamps).  Using a bench or angle grinder work these pieces clamped together until they are identical, then drill out the same holes in the second piece using the first as a template.  To drill the holes in the second piece, the most critical part, perfectly just keep the two pieces clamped together and drill through the existing holes in the first piece into the second piece.  You should now have two identical pieces.

In order to prevent scratching of the motorcycle frame once the can is mounted we used a little adhesive (you don't need much, it will be bolted anyway) to put a very thin strip of a foam rubber material similar to neoprene but more like foam on the plates on the inside where the piece will go against the bike.  The material we used came from a box that held a helmet camera I bought, anything similar should work.  You could also just use a couple of rubber washers... or gasket rubber... this stuff was just pretty good since it would help form a uniform surface against the very slightly curved surface of the bikes frame.  If it deteriorates over time I expect I would use some gasket material to replace it.

Now just use the drill to knock out the holes in the rubber material for the bolts.

<p>Great job, I added a piece of carpet cut to fit also for more noise cancelling. I cant seem to find ammo boxes over here (NI) bigger than the smallest ones (7.62?) im looking for the size you have here but shipping keeps killing it.</p>
<p>Where is your gal going to put her feet in your lap. Although I like the concept with the can's, I would paint them the same color as the bike so they blend in. I ride a 2000 Yamaha Roadstar Silverado what size do you think would look good and not over killed because I don't want to loose the use of the rear foot rest. I'm going to send a pic of my ride so you can kind of get a good idea okay. Since I can't seem to sell it maybe this ammo cans might help.</p>
<p>you can use some neodymium magnets to hold handles during ride, instead welding, because they loose functionality when are welded</p>
<p>Once i get my 250 Vstar I'm definitely going to do this, and make my own windshield! Im happy i found this site!</p>
I am absolutely going to be adding this to my Honda Shadow ACE!
I'm not very fond of harleys but I've got to say, the ammo cans on the sides make them look sick!
Very nice. Thanks for the guide. i used 25mm ammo cans for mine. just need to paint them now.
Thanks, those look great. The one problem I considered when we discussed painting them is the sheer amount of friction where the lid brackets contact the box when taking the lid on and off ruining any sort of paint job. If you solve that post back here and let me know what you did.
Here is my final project all put together waiting to be ridden. I thought of the friction too with the lid, but its something that is just gonna happen one way or another. I DID however just use a little bit of force and try to open the wings on the lid so its not SOOO tight but still tight enough for a full seal. Besides that, just cant treat them like normal ammo cans, gotta take the lids on and off somewhat nice haha.
Very nice!
Got it! Thanks for your time. Off I go ammo can shopping.
Sometimes one can think they have a unique idea then behold the wonders of the internet. I wanted to add Ammo cans as saddle bags to my street bob for quite some time now. I'm glad I typed it in and saw your detail. Awesome! However, I don't understand your leveling technique with the exhaust pipes and using the bubble level. Did you use the level for a horizontal level or vertical level? I don't think I know how to ask what I want to ask but if you can detail it differently I'll try to track.<br><br>Thanks!<br>
It was to horizontal level, but the reason it's tricky is because we leveled it by first putting the bubble level on the mounting plate... which was not level when holding the bike vertical. It would be very hard to accurately just hold the box up to the bike and make markings on the bike that could be drilled out and be in precisely the right spot... and we wanted the tolerances to be very tight so the holes could be no bigger than the diameter of the bolts, because that would weaken the structure and leave the cans somewhat unlevel, or worse, uneven between the two sides.<br><br>So we put the bubble level on the mounting plate attached to the bike, then raised the low end of the level until it was, level. Then we measured to find the angle difference off of level. Once we new the angle off of level we were able to take the bracket back off, place it on the can using that angle to mark for holes on the box through the existing holes on the bracket.<br><br>I hope that all makes sense. The other options we considered were making one of the box holes more of a slot about an inch long so the box could be adjusted as it was being mounted. If our angle system didn't get the boxes perfectly level and even with each other this is how we would have made the correction, but we didn't want to start with that because we wanted to maintain as much structural integrity as possible. Another consideration was short pieces of cotton wick placed in the bolt holes on the bike with a bit of paint on the end so the box could be held up evenly to the bike and pressed against that to make marks... but we weren't sure how accurate that could really be. Good luck, post pictures if you do it.
Once you've made the brackets, where on the bike are you mounting them? Thanks.
Hi... most motorcycles have a two bolt pattern on the rear fender specifically for mounting bags. It may look like they are just there to hold the fender on, but they usually pass through the frame and are quite solid for this purpose. Hope that helps.
Chrome them dude.... Then they would be killer!!!!!!!
I love this idea. Its Manly and pretty cheap. Not sure if it'll go with crouch rocket. Maybe if I were to paint her MASH Olive drab and through some stencils on her... EIther way love the idea good work ; &gt;
u may be able to do it on a crotch rocket with some plastic modification, maybe not as big as using a 40mm can. maybe a 50 cal or 7.62 would be best. not huge but they still hold alot.
Or maybe a single can mounted behind the back perpendicular to the bike instead of on the sides.
thats possible too but that will depend on the model and year of the sport bike. because more recently they have been being made with the exhaust coming out under the rear seat. I'm intrigued now, i'm going to look into doing it for my bike. great instructable btw.
For taller bikes and a narrow profile (Dualsports and trail bikes), try the 81mm mortar cans. They are about 24&quot; tall, and just wide enough to fit beverage cans, about a case and a half on each side. I used brackets to pin the bottom corner to the passenger pegs for stiffness.<br> Detachable brackets let you use them as stools when you hit the campsite.
a very great instructable: good how you not only describe what you did, but also why you did it that way, and which alternatives you rejected. <br>Great result as well.<br>I think chroming is the way to go.
Thanks. I think chroming would look awesome, I'm just thinking it would probably cost a few hundred bucks, but I haven't gotten a quote or anything. I also haven't looked into how much weight chroming would add.
I think those ammo cans would look great on a V-star mocked-up to look like a '42 WLA <br>http://www.worldofstock.com/slides/TRO1700.jpg. Strong work, Panda.
I really like this. A lot of commercial saddlebags are terribly expensive and many seem to want to eventually crack at their mounting points from vibration. You have inspired me to check into making a pair of these for my Honda Silverwing. I'll have a bit of a challenge negotiating around the exhaust system, but I think it will be doable. I have crash rails on the back, which should be a good possibility for mounting the ammo cans. Thank you for this Instructable!
Thank you for the kind words. Throw up some image links if you end up sticking a pair of these on a Silverwing, I'd love to see it.
Those hold practice grenades for the MK19 automatic grenade launcher, they are used for &quot;weapons familiarization for basic trainees. <br>If i remember correctly from being on &quot;ammo detail&quot; they were powder coated.
Yeah, I was a Marine and remember most of these cans vividly. I'm pretty sure it is powder coating, it comes off like powder coating (difficultly)... but I can't say with certainty. Either way I don't want to breathe it, but it would be cool to have a pair powder coated something cool... if I could find it for less than I've seen powder coating going for online. The rails on this can make it really really stiff compared to some of the other ammo cans I have around the house.

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