The aerodynamics of an open top box at speed

[Gone in 60]

I had an interesting lesson in aerodynamics this morning. One of my projects during the holiday week was to tune up my Givi V47 top box. Givi sent me a warranty replacement for a cracked piece of trim on the latch years ago, but I never bothered to replace it until last week. Doing so made the latch as stiff as it was when the box was new, which I didn't pay enough attention to.

Since my wife made some treats for me to take to work to hand out for New Years, I used the V47 today. I packed it with my lunch, wallet and the plate of treats. On top, I had a stack of loose paperwork I needed to take to the office. During my morning routine as I suited up in the garage, I gave the lid a push, turned the key, and put it in my pocket. I didn't push hard enough...

Once I got to the freeway, being New Year's Eve, the morning commute was extremely light, and I was going about 80 mph. A few miles in, a car pulled along to the right of me and was motioning. I thought it was a "Cool Bike" thumbs-up, until I caught my shadow on the road. The silhouette showed the lid to my Givi standing straight up.

With the light traffic, I was able to pull to the shoulder easily, stop, and wince as I walked back to see what was missing. Thankfully, only the papers had blown out, and my wallet, lunch and treats were secure. I reprinted the spreadsheets when I got to work. But I've been mulling the aerodynamics of the thing to think of how the air movement would lift the lid of my top box and keep it vertical while riding at speed.

[Houtman_imp]

I personally do not like top boxes for their looks on our bikes and I would have difficulty getting my leg over it as I am not agile at ALL !

[peterbaron]

John,You need to carry with you a little stool....

[Gone in 60]

I don't like the looks either, but I really don't care if I impress anyone on the 55 or the 405. I'd rather it just haul my lunch! As far as agility, I do need to remember to pull my leg in just a bit when I use this one to avoid scuffing that silver trim band that runs around it.

[Charlie Bravo_imp]

I have two bikes with top boxes, and I've removed them both. I prefer bags. The Bmr has of course hard bags, but the Honda and the Suzi both came with top boxes. I don't like their looks, but of course, they do carry a lot of stuff. If I have to, I remount and use them, but if I don't need the capacity, they're offa there!

[Lord Popgun]

Both my bikes have top boxes and I like them.

If I had a Trail 125 I’d put a milk crate on it!

[GoldOxide_imp]

I don't like the looks either, but I really don't care if I impress anyone on the 55 or the 405. I'd rather it just haul my lunch! As far as agility, I do need to remember to pull my leg in just a bit when I use this one to avoid scuffing that silver trim band that runs around it.

Gin60: All luggage takes looks away from the CB1100 - so it seems to many. Top boxes add that bulbous look to the rear, however, yours looks better than average - incredibly.

As for mounting the beast: Do it adventure bike style - with side stand down, mount the left driver peg with left foot and swing your other log over the saddlle. Bob's yer uncle.

[Gone in 60]

You want bulbous? Here's bulbous. The V40 is my normal go-to, since it's smaller and lighter and holds the stuff I usually take back and forth from the office. Looks like a Weber barbecue on the back of either bike, but when I get to work, it clicks off and I carry it in like a briefcase.

And yes, I get a lot of grief from the Triumph purists who say I ruined a perfectly good Bonneville. But, the rack is held on with six screws, and if it bugs me enough, it comes off with one Allen wrench and ten minutes.

Givi makes a trim piece for the V40 which I'm thinking of buying to break up the black bulb look, but I don't think fifty bucks worth of additional plastic can polish this very practical turd.

[clearviewx]

I love my Givi Top Box

[Gone in 60]

Just keep it latched, Clearview!