GS500 towbar, aint that mad as shaZam!

[kapiteinkoek]

But wait, what how wtf.

Well, its not that hard really. Basically the GS500 is pretty much designed to run twice its own weight, which means you can tie another GS500 on top of your GS500 and you will be fine. Ofcourse its kinda hard to drive then so I figured better stick to a trailer that is a little less heavy so it can carry me too.

Also keep in mind that its an aircooled engine so dont take it out like this when its frying temperatures outside and try to keep moving so you have airflow.

I planned on taking it for a Scandinavia tour, a suitable climate for this combination. Unfortunately this combination turns out to be only semi-stable. If I give the handlebars a push the bike and trailer start to oscillate for a bit then stabilize. Even though it does stabilize it does that way too slowly for my taste and I'm afraid an unexpected situation will get me in a bad uncontrollable swing. My required speed is 50mph while right now its only suitable for 30-40 mph.

Some technicalities:
Max tow ball pressure: 50lbs. Because of the rigid connection with the rear end preferably max 20lbs
Max tow weight: Legally I'm only allowed to pull 50% of the self weight of the bike (which is about 210lbs) and thats a good value to keep as max. The frame is good to go for 550lbs though.

Frame is connected to the rear by a longer axle (comes from a Muz Skorpion) and simply clamped into place. Electrics are done with standard plugs so its 100% plug&play no modifications to the bike needed. Trailer lights are LED to avoid overloading the GS500 system.

I figure the semi-stability is caused by a combination of the short though wide trailer and GS500 characteristics. I think I might be fine with a smaller trailer but I dont have time for that yet.
This aint done yet and rock on ladies 

[Big Rich]

I've always been leary of trailers behind motorcycles - but I know it's been done plenty with zero incidents.

That being said, have you seen the trailers over on ADVRider ? There's some cool stuff over there.... single wheel trailers, two wheel trailers that extend into a sort of bivy / cot, etc.

[kapiteinkoek]

I've always been leary of trailers behind motorcycles - but I know it's been done plenty with zero incidents.

Its probably because we dont want to die. Like I stated I don't trust this combination enough to take it for an extensive tour so I dont. You cant get away with much on a bike eh 

[ShowBizWolf]

This is sooooo interesting! Thank you for sharing... I would totally take it for a spin

[kapiteinkoek]

I discovered that if you put a girl on the buddy seat the combination is rock stable up to 53mph. Above that there is still some slight swinging if you give the steer a jerk, but its pretty insignificant and dampens almost instantly. Some weight above the rear wheel does the trick.
Apparently I could have taken it for the scandinavia tour after all. I'll take it there for a spin next summer 

[Bluesmudge]

I love stuff like this.

I always wanted a single wheel trailer with suspension for my bike, but they cost as much as a used GS!

[kapiteinkoek]

This was about $150 and a week of sweating. I found a small and cheap trailer on the national ebay equivalent



Add some common trailer parts, some steel and some bolts and you're almost there already. I made the box of scrap wood I brought home from work. I pretty much put the whole thing together with a battery drill and a hand (metal)saw.
Oh forgot, spent a couple of bucks at a local blacksmith to weld 2 pieces of steel together to serve as holder for the 360 rotatable connector.

[chopper7020]

Sweet if I ever get my 95 going I'm following your lead. I already have the trailer! Excellent for touring around on a budget I would think. Thanks for this!

[nathaniel2910]

Could you upload a few more pics of the towbar  pretty please

[kapiteinkoek]

Didnt quite understand that question, what do you mean?
Ah you already edited it. Yes I will post some more pictures very soon.

I'm still working on it btw. I finished painting the box today and already extended spine of the trailer. Also installed some little gas springs to keep the lid open.

I should have it on the road this weekend or somewhere next week.

[nathaniel2910]

Nice one
Have been nagging my colleague to let me cut down a trailer he hasn't used in a good few years,
Just a thought since car tow bars are attached to the body, wouldn't it be better to have the tow bar attached to the subframe? I've seen other projects mount to the subframe and I don't recall them having stab ability problems below 70.
Could be wrong though

[Big Rich]

Nathaniel, there are so many variables involved and I personally am not the guy that can explain them. But yes, mounted to the frame is generally the "ideal" way to mount a tow bar. The bike itself is only rated for so much weight total (the gvwr). Adding a trailer to the swingarm moves weight to the "unsprung weight", which is avoided in general. If you think about it, when the rear wheel hits a bump, the shock allows the swingarm to move upwards to compensate. With a trailer attached to the swingarm.... the shock has to move the tongue weight upwards along with the rest of the unsprung weight. And there can be rebound issues, bouncing issues (the trailer tire will hit the same bump), etc..

I'm not saying that motorcycle trailers are tools of mass destruction. ...people use them every day. But there is SO much to think about when adding one. To me, honestly, they are very intriguing. I'd love to add one for the capacity and functionality .

[kapiteinkoek]

I put a lot of thought into that and I went for the axle mount anyway. First of all because its easy and second because when mounted to the axle you pretty much won't notice the trailer when its behind the bike (when its a stable combination ofcourse). When mounting it to the subframe you will very much notice that something is jerking the back of the bike and when you use the brakes the trailer will push the tail of the bike up, decreasing stability when you most need it.

Increase in unsprung weight is easily compensated by lowering speed on bumpy roads. I don't have a lot of bumpy roads here so thats not really an issue.

[kapiteinkoek]

Put the whole thing back together today. Everything is stable now, can do 60mph without problems. Lack of stability was caused by a poorly adjusted steering bearing and a too short trailer frame.



Extended the frame, will replace it by 1 aluminium piece later.


Installed some small gassprings to keep the lid open. Cargo is a pack of woodchips for my bunnies.


It was done on a budget so don't mind the worlds shittiest paintjob. Will remove rust and repaint the wheels later.

More pictures of the construction:
Electrics are connected with original plugs so no modification to the bike needed

Ran out of wire so its a bit of a mess but it works








Will also install an oil temperature gauge to keep an eye on the engine temperature during summertime, traffic jams etc. Also going to make a small fender/hugger to protect the towbar from water/sand coming from the wheel.

[ShowBizWolf]

That looks so cool... and I love the color of your bike 

[kapiteinkoek]

Thanks, its the original ocean blue. The original wheels are anthracite but I stored those because I buy 2nd hand wheels with good tyres on them. Its cheaper than buying new tyres. I switch the wheels and store the ones with worn tyres in my shed. I have a whole stack of them now 

[tb0lt]

This might help with your stability issues. https://www.google.com/search?q=trailer+sway+control&gws_rd=ssl

[kapiteinkoek]

No need for that because everything is stable already!