single wheel trailer project: COMPLETED

[virus]

Well after single seating my GPZ I decided I need more space for camping kit, however I didnt want to make it a full 2 seater again as I like the minimal look, so my mind went onto trailers, I did a bit of research then got started.

Now the law states that:
* The towing motorcycle must exceed 125 cc engine capacity.
* The trailer has an overall width not exceeding 1.00m
* The distance between the rear axle of the motorcycle and the rearmost part of the trailer must not exceed 2.5m.
* The Motorcycle must be clearly and indelibly marked with it’s kerbside weight.
* The Trailer must be clearly and indelibly marked with it's unladen weight.
* The Maximum towed weight, including the trailer and it’s load must not exceed 150 Kg (330 lb) or two thirds of the motorcycles kerbside weight, whichever is the least.
* The UK speed limit is 60 mph on Motorways and dual carriageways and 50 mph on all other roads unless a lesser limit is in force.


So with that in mind (and a welder borrowed from my mate) I got started on my first welding project, ive never used arc before so this should be a good test.
My plan is for a 50cm wide (to match the flashbang crate in the pictures) 3ft long single wheel trailer, with no real body on it, just a chassis for me to strap my camping kit to, using a universal joint from a steering column/drive shaft as a hitch.

Here is the progress from day 1.


https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/day1start.jpg
materials ready, plan for day 1 is to make the light rig for the back.


https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/startinglightbox.jpg
area prepped for first weld, 1 strut on each side from the large piece of metal, and the middle section on top to form a box.


https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/socketbodge.jpg
welded an old imperial socket in...


https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/socketindi.jpg
to mount the old z250 indis.


https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/mockup.jpg
First mockup of the trailer.
https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/mockup2.jpg
planned to be 3 foot long, giving me a bit of space inbetween it and the rear wheel for hitching up, and 10cm spare at the back before it gets illegally long.


https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/day1end.jpg
and the end product of day 1.


the brake light cracked and fell off whilst I was chipping the slag off some welds, and the right hand indi also needed more work/bodgineering, but im pleased with the progress so far.

the pieces of box section sticking out are for storing the trailer vertically when not in use, which will come in handy for my garden.

the plan for the suspension and rear wheel is to use a moped front end, i.e wheel forks and yokes. This will be bolted and welded (for extra security) to the bottom run of the light rig. If anyone has a moped front end going free/cheap then let me know, this project is definitely on a budget (incase you cant guess )

More progress and and when I get the parts together.

Cheers
John
____________________
own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.

[TimNorwich]

Looks cool, very interested to see how it ends out! Keep up the good work
____________________
Speedshite 50cc > Honda XR125L > Kawasaki GPZ 500 S > 02 Honda Hornet > 05 Honda CG125 winter hack > 04 Kawasaki ER-5 > 99 Honda Hornet 600 > Kawasaki GPZ 500 S > 99 Honda Hornet 600 > 05 Honda CBR600F > 01 Honda Hornet

[twotakt]

Have only ever seen a few big cruisers using trailers, all of which looked to be "one off" home made jobbies. I don't think anyone is making them commercially?? I bet cornering with it on will feel strange.

Looking forward to seeing this finished.
____________________
R.I.P. Tareree Shiimi, 1985-2008

[Dr. DaveJPS]

[NiteMare]

i'd suggest you use this as a mock-up then get a competent welder to do your real one ...

how do you think you're gonna feel if/when your welding fails and your trailer hurtles across the motorway at 60mph maybe taking out one of your mates whilst it's an unguided missile....

not to mention the legal repercussions of such an incident ...

i build trailers reasonably regularly, occaisionally repair small truck chassis and just rebuilt the front end of my landrover chassis....

if your welding is of such poor quality that even an indicator falls off when clearing the slag/flux, i can imagine just how fast the frame will fall apart once loaded and vibrating it's way down the road...

honestly, don't fuck about, do it properly for peace of mind

this is a link to the work i've done on my landy, i now intend to take it offroad soon and fully trust that i won't be having the chassis snapping and leaving me stuck in a big muddy hole..
https://s259.photobucket.com/albums/hh311/NiteMare_08/Zebedee/
____________________
it ain't broke...

i ain't fixed it enough

[virus]

[virus]

no major progress today, spent most of it out hunting on the bike for metal/parts


got the basic frame together, I plan to get some 2mm plate and brace the corners properly though, also ive got a brace or 2 across the middle to go on.
https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/day2mockup.jpg

found a set of UJ's not sure if they are strong enough though, any ideas? I guess Im going to need a propshaft job rather than this reliant steering column one.
https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/ujs.jpg
https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/ujsize.jpg
excuse the crap pictures, 2mp camera phone

As It stands I cant really get to work on the hitch until ive worked out my ride height, which will depend on the wheel (currently non existent) so tomorrow Im going to finish the frame and start bracing it up.

Cheers
John
____________________
own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.

[colin1]

This is interesting, but if a trailer on a car managed to put some people off bcf in hospital, I cant help thinking that a home made motorbike trailer might be even more dangerous if anything goes wrong.

Hopefully it won't.

However my rideout tactic of riding at the back to avoid problems, wouldnt help me if I'm riding behind a bike with a trailer.

Maybe a really long gap might.
____________________
colin1 is officially faster than god

[virus]

Colin, I think your safe.

Even if it does disintegrate (highly unlikely considering the amount of bracing planned) you should be fine, this thing wont see many ride outs, Its designed solely for rallys and touring.

Cheers
John
____________________
own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.

[NiteMare]

the reliant uj's in good condition should be strong enough for your hitch swivel without any problems, just try to keep the UJ sqare (or close to square) to give best articulation and lifespan...

it'll be even better being as you could use the steering column splines as part of the towbar allowing you to slide the trailer mounted UJ on and off and just pop the clamp bolt in and tighten ...

it'll be secure as long as the clamp bolt has a recess in the column shaft to stop it sliding off with vibration ....

never ever be tempted to "just nip it up" as the weight and vibrations will start wearing the splines and eventually allow the trailer to fall over...

i'll be watching this thread with interest, not that i ever plan on having a trailer behind my bike, i just like problem solving ...

just a thought here, would it not be worth using a single scooter front wheel in an extended tubular swingarm and a small roof box (car luggage thing, scrounge on freecycle, yahoo groups)
____________________
it ain't broke...

i ain't fixed it enough

[Vincent]

Why not beef up a pushbike trailer? Might make a good starting point.
____________________
Space Is Deep

[virus]

[Vincent]

[virus]

The main job this will have is carrying my camping kit for my 2 week Scotland tour later in the year, I don't envision that coming in over 150kg, but Im trying to over engineer it (never know when I might need to move an engine etc on it).

Cheers
John
____________________
own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.

[Vincent]

[NiteMare]

i'd use one of those UJ's happily for the tow hitch as long as they move freely without any slop (just looked closer at the photos) , the rusty shaft "should" have a rebate to locate the bolt...

i doubt i'd look for a propshaft UJ as that would be a bugger to bolt to the bike with a flange and four bolts to do up (off a car), or as per my wing prop, it just slides into place with nothing retaining it apart from a circlip
____________________
it ain't broke...

i ain't fixed it enough

[virus]

Not much done today, spent most of it hunting for metal, and found a scrap bin within walking distance of my house, so I might go back tonight with a large rucksack.

Most of todays work was bracing the chassis.
https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/bracing.jpg
https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/chassisday3.jpg


But I did make a start on the hitch bracket, which is designed to slide into the remnants of my subframe, and will be bolted in place with high tensile bolts, the UJ will attach to this, and use the spline (seen as it does have a recess for a bolt) on the UJ to attach the trailer. That way I can quick detatch the trailer when camping, and remove the whole frame for it when Im not towing.

https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/hitchbracket.jpg
https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/hitchbracket2.jpg


Cheers
John
____________________
own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.

[virus]

Well its been a while since I updated this, ive not done much really, infact ive undone some things.

The middle braces are gone, and in the space will be my indespension unit and 8 inch wheel, mounted onto a very thick plate going all the way over (to incorperate a mudguard aswell).

Heres the indespension unit I found, Just need to find a 8 inch, 3 stud 86mm PCD wheel for it because the one I have is rusted to buggery.
https://i251.photobucket.com/albums/gg307/virusjohn/gpz%20trailer%20project/indespension.jpg

the other thing ive gone back on is my mounting point, seen as the chassis with the wheel in sits at about swingarm level, Ive started thinking about it again.

This brings me to a question...


a) propper towhitch mounted on swingarm
b) propper towhitch mounted on rear subframe
c) UJ mounted on swingarm
d) UJ mounted on rear subframe

Im leaning towards option c at the moment, considering theres minimal space on the rear subframe.


Cheers
John
____________________
own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.

[chris-red]

Putting it on the swingarm is a bad idea IMO,

Loads of extra unsprung weight also more vibrations and movement through the linkage.

Go knows what it would do to the handling nothing good thats for sure.
____________________
Well, you know what they say. If you want to save the world, you have to push a few old ladies down the stairs.
Skudd:- Perhaps she just thinks you are a window licker and is being nice just in case she becomes another Jill Dando.
WANTED:- Fujinon (Fuji) M42 (Screw on) lenses, let me know if you have anything.

[ms51ves3]

[virus]

[NiteMare]

you'll struggle to find a 3 stud wheel

do not under any circumstances attempt to mount the hitch from your swingarm

and looking at your attempts to weld i really do advise you to consider this as a template for someone who can weld to build the real one for you ..

your welding appears to have next to no penetration and looks to be pigeon shit just blobbed onto the surface of the material you're attempting to join
____________________
it ain't broke...

i ain't fixed it enough

[twostroketit]

Don't mount it onto the swingarm,mount it onto the frame/subframe. You never see a car with the towhitch mounted on the back axle,it's just never going to be safe like that. Will a citroen 2cv wheel fit on that hub? They're a 3 stud fitting.
____________________
sup up your beer and collect your fags

[b-f-c]

[virus]

So I completed the trailer, 2 DAYS before rat and survival, then took it for a test run, this resulted in me being thrown off the bike and the rear sub frame i made for the hitch bending and in one place breaking (on the metal not a weld though, so that gave me confidence in my welding)

so 1 day before rat and survival I chopped off the hitch tube, realigned it with the wheel to try and get it to pull straight, and then fabricated a new rear hitch sub frame.

Here is the results:

https://i251.photobucket.com/albums/gg307/virusjohn/rat%20and%20survival%2009/S8000083.jpg
https://i251.photobucket.com/albums/gg307/virusjohn/rat%20and%20survival%2009/S8000087.jpg
https://i251.photobucket.com/albums/gg307/virusjohn/rat%20and%20survival%2009/S8000112.jpg
It was a bit of a muddy field at R+S

https://i251.photobucket.com/albums/gg307/virusjohn/rat%20and%20survival%2009/S8000159.jpg

Unloaded, it tows pretty well, obviously Its a pain to reverse, U turns are harder because the prop joint locks over quite soon but it pulls well and is only noticeable on very bad roads. Loaded up its not too bad but the wobbles set in a lot quicker and b road hooning just isn't possible.

All in all, I'm glad Its done, current plans are to replace the bearing in the prop joint, brace the hitch sub frame a bit more and give it all a bit more paint, then its back to the corner of the garden until the next rally/touring/massive beer run.


Cheers
John
____________________
own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.