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I have a friend who is an Engineer with Siemens rail automation and i had a long chat with him about this problem (yeah you scared me a bit) He did some digging for me and came back with his idea, that the loading is more about stacking too much weight behind the rear wheel. With an amount of weight in the box, rider + passenger the risk is NOT the rack breaking but more that you might be going up an incline, give it some juice and end up with the bike on top of you. Structurally speaking he thinks 20-30kgs without a passenger would not be an issue at all but without knowing more he would NOT guarantee it, only his opinion. Having said this, i will carefully watch the frame and rack for any signs of failure. When i have a passenger i will be using the box for the 2 helmets more than anything else, when i travel i plan to put anything with weight in a bag strapped between the box and myself and use it for some back support.
I think your Siemens engineer friend has the right idea, but he (and I) didn't go far enough. More below.

It's not just the loading (inside the top box) that matters, but rather the lever effect which may break the motorcycle's tail.
✋ Using the diagram above (rear frame): the further the load is from the screws 3 / 4 the higher the risk of breaking the tail is.
See moments & levers... to understand how it actually works.
Yes, I agree, this is important, but the specifications for the bolts holding the rack vastly exceed the static loading I postulated. Key word, static. More below.

The user manual for my ym. G310GS says maximum 3 kg in the topcase.
Yes, I saw that, my manual discusses a "topbox" with a 5kg max payload and a "topbox light" with a 3kg max payload. Since both are allowed, then the heavier of the two is the best choice to use as the rack's max payload (i.e., the above 3.12 kg + 5 kg = 8.12 kg). Also, I checked that all model years from 2016 to present have the same part number for both the luggage rack and the rear frame, so model year isn't an issue.

From the page 108 "Topbox" section of my manual...
Font Rectangle Screenshot Number Parallel


From the page 109 "Topbox Light" section of my manual...
Rectangle Font Parallel Number Circle


...continued on page 110...
Font Rectangle Electric blue Number Brand


Now, the rest of the story...

After reading the scenario postulated by D1v1ine's Seimens engineer, it occurred to me that the most strenuous scenario isn't necessarily flipping the bike backwards. The most strenuous scenario is hitting a pothole at high speed, the kind of pothole that might bend a rim. Such an impact would greatly magnify the effect of the combined weight/moment of the topbox and contents on the rack and rear frame as a lever arm. In this scenario, particularly after repeated potholes over time, I think stress fractures followed by failure is entirely possible.

So, summarizing, do watch the frame and rack for signs, but be especially diligent after a significant pothole or pothole like event. If I were you, periodically, but especially after a hard pothole like event, I would expose the rear frame by removing the plastic panels covering it; have someone hold the bike upright by sitting on it; and I would put my full body weight on the rear of the rack while looking for cracks. Of course, as you friend postulated, be cautious that the weight might make the bike more likely to wheelie or, in the extreme, flip over backward. Last, as mentioned by @ARBOLMANO above, but also worth repeating, be cautious as you ride with it the first few times, that the airflow and top heaviness may cause changes in how the bike handles, especially during abrupt changes in speed and direction and/or windy conditions. If I were you, I would load up the topbox, find a safe place, and practice maneuvers to see how the bike behaves with the extra weight in that location, slowly and incrementally working your way up to full speed emergency maneuvers (e.g., braking in a straight line, braking on a curve, accelerating, swerving). Watch out for hard swerves, significant topbox weight might make the front tire skip. I've done this a few times; I haven't gone down because of it, but it's truly a heart stopping moment if you do it yourself or if you have to watch as one of your students does it (I've done both).

I think I've reached my limits on this; I hope it helped. JerryG
 

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Hey all,

next month i need to do an about 3500km total trip and i am thinking about using my 310gs. 80% of the trip will be on 110km/hr freeways from Gold Coast to Canberra Australia with 2 side trips at 800km and 400km respectively. I have already fitted usb charger, quad lock, hand guards. Not going anywhere remote, plenty of fuel stations etc, i have a top box coming in the next few days and i am hoping to put a nice back between the box and myself for some lower back support. I have had the 1k service done and will be at around 4k on the odometer when i leave. Any advice? Bike can handle it?

I can think some issues will be right hand fatigue and foot vibration when the speed gets high.

Any advice would be appreciated.
Hey all,

next month i need to do an about 3500km total trip and i am thinking about using my 310gs. 80% of the trip will be on 110km/hr freeways from Gold Coast to Canberra Australia with 2 side trips at 800km and 400km respectively. I have already fitted usb charger, quad lock, hand guards. Not going anywhere remote, plenty of fuel stations etc, i have a top box coming in the next few days and i am hoping to put a nice back between the box and myself for some lower back support. I have had the 1k service done and will be at around 4k on the odometer when i leave. Any advice? Bike can handle it?

I can think some issues will be right hand fatigue and foot vibration when the speed gets high.

Any advice would be appreciated.
G'day - I'm in Nabiac and Sydney (between the two) - if you're after some company on my GS310 - could ride part of the trip with you - could be good.

Matt
 

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did a 10k trip to the tip and back last sept/oct, with 38l panniers, 45l top box and 50l bag on the back seat. bike handled it fine. GC to Canberra, no problem at all.

regarding weights in the boxes etc.. too much weight will also make your mates laugh at you when you drop the bike on the side stand and it falls backward 😂

on the highway sections from Sydney to cairns (via Karumba) I had 25kg in the top box and 12 and 13kg in the panniers.
blue bag was around 5-10kg (wets, warm liners, drinks from the servo etc)
Tire Wheel Fuel tank Vehicle Automotive tire
 

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Discussion Starter · #25 ·
did a 10k trip to the tip and back last sept/oct, with 38l panniers, 45l top box and 50l bag on the back seat. bike handled it fine. GC to Canberra, no problem at all.

regarding weights in the boxes etc.. too much weight will also make your mates laugh at you when you drop the bike on the side stand and it falls backward 😂

on the highway sections from Sydney to cairns (via Karumba) I had 25kg in the top box and 12 and 13kg in the panniers.
blue bag was around 5-10kg (wets, warm liners, drinks from the servo etc)
View attachment 18136
Brilliant pic in the mud Matt,

Regarding weight, are the side paniers supported off the frame/rack? If they are i would have to guess about 50kgs with boxes plus contents?
 

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Brilliant pic in the mud Matt,

Regarding weight, are the side paniers supported off the frame/rack? If they are i would have to guess about 50kgs with boxes plus contents?
bikes at home, im at work but I can check later.
from memory, there's two bolts from underneath the factory rear rack, the hepco rack bolts to this and also to the pillion peg mount.
 

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I’d go with the rating of 11lbs on the rack. But it’s just a rating, an advised limit. Exceed at your own risk. It’s a wee bit daring with aluminum. Al does not flex well, in fact it often just breaks rather than flex. So lashing your load for low flex is a goal. A behemoth box might well be placed such that part of the load is borne by the seat. This spreads the load and hopefully lowers the amount of flex. Plus weight is best placed near the CG rather than on lever arm. The “no hassle man“ is correct as usual, best policy is to carry less stuff. But easier said than done. I personally have always detested a top box, preferring the hard panniers. But the 310 is a wee bike not suited to panniers in my playbook so I’ve a smaller top box for my gear around town use. When I go tripping, I’ll probably take off the box and go with just a large dry bag and small pack strapped to rack and part of seat. I originally thought the top box would be handy but it gets in the way of longitudinal loading of things like tent poles and me cot.
Off road the top box can get in the way at times boarding in off camber situations and picking it up when it’s nap time. There’s quite a bit of room under the seat in the plastic side trim. I’ve got my entire tire kit and pump there, along with tools to adjust suspension.
 

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Discussion Starter · #28 ·
@GS Matt, only reason i ask is someone mentioned breaking the tail of the frame, so if its all being supported by the frame it would be no better for me to add Panniers.

@ARBOLMANO, love a clean bike also, but since Diesel hit 2$ a litre it kinda got me over the line with the wife to buy the bike, so being able to grab some groceries, run the kids around to their different sports etc Only reason my wife wasnt keen on the idea of a bike was a live on anti-coagulants (clots/PEs) and any accident could be really bad for me hehe

For the trip, i am not camping, weight of gear in the box i would guess 10kgs max (shoes, a few snacks, few drinks etc), back seat maybe another 15kgs (clothes mostly). Since i am straight down the east coast of Australia, bike came with 5 years full roadside which in my experience has been brilliant with every other vehicle i owned so i will bring limited tools and gear, some chain oil and cleaning cloths.

Is the rack pure aluminium or an alloy? Aluminium i agree will just snap with little/no warning, but there are alloys that are a lot stronger and almost all manufacturers state everything is Aluminium when there are alloys that are cheaper and stronger? Most auto housing and transfer casings list as aluminium but take it to a welder and they will correct you instantly about the metal type it is. Personally i have no idea.....
 

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Really the construction of the rack is such, I bet it wouldn’t break with 50lbs. BMW has to put some limit to be safe. Maybe even based on the max weight that won’t adverse affect handling? Just be aware of situation. We all tend to fill available space given opportunity.
 

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Hello Arbolmano,
here a statement about loading. In 1982, me and my wife went on a Corsica trip. Back in the days wI drove a BMW 750 and my wife had a 250 fore stroke single cylinder Yamaha. We carried a cotton Boyscout tent, 2 folding chairs, a rolling table, 2 kerosin lamps, 2 camp gas stoves, pots pans plates cutlery, 2,thermarest, 2 sleeping bags, clothes to change, raingear, we had leathercombis,and a harpoon with fins and diving mask and all kind of food, a 3ltr. container for wine(really important),and other small items. When ever I get a chance to scan in my old paper pics I will post them. You have to be crazy to do things like this, but it helps.
I drove all over Europe with my wife on motorcycles and this was our standard. Except for the harpoon, this was only because we went to the Mediterranean Sea.
 

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Hello Arbolmano, here a statement about loading. In 1982, me and my wife went on a Corsica trip. Back in the days wI drove a BMW 750 and my wife had a 250 fore stroke single cylinder Yamaha. We carried a cotton Boyscout tent, 2 folding chairs, a rolling table, 2 kerosin lamps, 2 camp gas stoves, pots pans plates cutlery, 2,thermarest, 2 sleeping bags, clothes to change, raingear, we had leathercombis,and a harpoon with fins and diving mask and all kind of food, a 3ltr. container for wine(really important),and other small items. When ever I get a chance to scan in my old paper pics I will post them. You have to be crazy to do things like this, but it helps. I drove all over Europe with my wife on motorcycles and this was our standard. Except for the harpoon, this was only because we went to the Mediterranean Sea.
@Määkipp Gang, your story reminded me of a picture I've been meaning to scan, so I did. Thanks for the nudge. Below is my twenty-year old self in 1979 and my new-to-me then nine-year old 1971 Honda CB750 with a Windjammer fairing. I was headed from home in Minnesota to college in Texas. Between/above the handlebars, I had a usually-in-the-dash automotive radio for music and a usually mounted-under-the-dash CB Radio for tracking the smokies (police). Yes, that is a full size suitcase on my left passenger foot rest; there's a second matching full size suitcase on the right passenger foot rest. The red box by my elbow is a full size tool box full of tools. I don't recall what was in the other boxes, but notice the gas can strapped on the back of my red, white, and blue Boy Scout back pack. I rode that motorcycle back and forth between Minnesota and Texas every summer, in and around Minnesota and Wisconsin during the summer, and out to visit my grandparents in Arizona and Colorado during school breaks. During those visits, I also camped at the Grand Canyon and rode to the top of Pike's Peak (14,115 feet = 4,302 meters high). Other than the helmet sitting on the seat behind me and an Army jacket packed away somewhere, what you see is how I rode back then. Crazy. Crazy fun too.

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:ROFLMAO:@Määkip & Arbolmano, The stories we could tell. And of course you both only went to "authorized" BMW/Honda dealers to for service and tire change ;) Can you imagine how much could be loaded in and on a Ducati SD900 Darmah with a sidecar? Well, we carried even more than that One of my former fiancés (later wife & ex) and I drove around continental Europe on such a rig. Unfortunatelly I lost all photos in the divorce, and the missus also left me.
 

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Ultra-Light = Ultra-Expencive. There's more on the subject of light weight moto-touring on Advrider
Yep. I'll be camping on/at the CABDR and DVNR in March. I invested in new lightweight gear awhile back, but this will be the first time I use it with my Reckless 80 on the G310GS. It all currently resides in a Mosko Moto Backcountry 30L Duffle/Pack that I carry on the luggage rack of my S1000XR to complement what I carried in the XR's 30L each saddlebags. That means I have to downsize from 90L to 80L; that will be a challenge since I also have to carry fuel and water on the GS that I didn't have to carry on the XR. More later.
 

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Nice bell bottoms Jerry G. Such a different time. No infernal net , no GPS no cells phones! Eek! I was always a minimal packer as I came from a background of backpacking/horse packing. Used same saddle bags for both for years. So much nicer now in some ways if more populated. Navigation and bikes have improved so much.
I can only imagine what no hassles Hassleman could pack on a Ducati sidecar! Did that affect to relationship? When she realized you had a moto “problem” did she ask the question “me or the motorbike?”. I had that happen with a girl when I was Cowboying she asked if I loved my dog more than her. I was honest and had to find a new gal.
 
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did she ask the question “me or the motorbike?”
She did when we were still dating. Then she rode pillion with me once and was hooked. A year later she took her license and we bought her a bike of her own. We married (did Wales & Scotland on a Moto Guzzi 1000SP for honeymoon), got kids, changes bikes for sailing yachts, bought new bikes when kids reached teenage, joined territorial defence (like National Guard) as dispatch riders (with Husky MC258A's), and divorced. Married 18 years, relation in total 23 years. Somewhere in between we also started an aikido dojo and some private enterprises.
 

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No hassle Hassleman. A lifetime of full on adventure, land or sea. With progeny even.
And lucky enough to life on in Finland. Not bad my friend.
 
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(somewhat off subject)
did a 10k trip to the tip and back last sept/oct, with 38l panniers, 45l top box and 50l bag on the back seat. bike handled it fine. GC to Canberra, no problem at all.


View attachment 18136
What is that vertical OD green bag you have mounted in front there?

(on subject)
to the OP - why not get panniers and keep the weight lower instead of the high-weight top box?
 
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