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single wheel trailer "on the cheap"

Posted: Tue Jan 03, 2012 2:22 pm
by ampster
this isn't a chopper build log, but it's mc related at least and considering all the talent that frequents here, I could use a some guidance/advice/feedback on this (considering what minimal metal forming skills/experience I've had).

I really don't know what to make of the apparent issue the moco has with pulling trailers. Read a few stories online about it and decided I would attempt to create a light weight trailer that should have minimal impact on the bike.

The bike this will be pulled behind is a for the most part a totally stock 2010 FLHTC with over 27,000 miles on her so far, and is out of the warranty period - although if a twist of fate happens and I have an extra grand + (yeahhh right!) I'll renew the warranty for a couple of years if just for this years trip to the west coast. One of my daughters will be going with me this year, thus the need for extra storage room. As I figure it now the bike itself will be fully loaded with just our riding gear (rain gear, chaps, helmets and such) so the plan is my daughter and I will each have our own bag to store our clothes in, one on each side of the trailer.

warning, I unintentionally ramble on every now and then and I will try to keep things to a minimum and not go over board.

The design I've come up with uses a rear swing arm from a kawi dirt bike which I've already bought off ebay. That swing arm - as used on the orig dirt bike - used a 12" wheel with a 12mm axle. I've up'd the size of the wheel to a 14" with a 15mm axle, which I've also bought off ebay plus some online retailers for odd parts (tubes, 14" street tire, swing arm & wheel axles, baskets, shocks, etc)

so far I've had a friend mill out the swing arm to accept a 15mm wheel axle and I have bought enough axle spacers for it (that will need some slight milling with the addition of washers on one side to get the wheel centered in the swing arm correctly)

After I had bought of lot of these items, I then went to the DMV of MN to find out what's needed to register a homemade...luckily I kept all the receipts although I don't know what to expect with the swing arm from the previous dirt bike - sounds like it may be an issue using something from a bike for re-use on a trailer. Guess I'll find out when I go to register it.

This design has changed sooo many times already it's become second nature to change things - so if anybody sees anything that stands out that is totally wacked or f'd up, say something please!

One of the last few changes I made was to increase the "bed" height of the trailer to approx 15" - I did this to get the lights up to min DOT requirements (15" and up IRC).

I'm still on the fence about the "spare wheel" as shown in the pics - hopefully with some early summer testing I'll find out how well the tread wears and decide if I really need a spare wheel assy or not. My original plans about a spare were to just bring along a spare tire and spare tube + tools that would allow me to change it on the side of the road. However...it was a bitch putting that tire onto the rim by hand and a friend asked me "why not just mount a complete spare wheel assy to avoid that hassle".

Oh Yeah, about the baskets...sure, I'd like to find a enclosed light weight container or two but that likely wouldn't happen unless I had it/them specially made. So I opted to go with baskets or cages that would hold a water-tight/proof bag I found at Cabalas that measure 12x12x24. The side baskets shown are 12x24 and the forward basket is 12x18 (good for a dirty clothes bag or cooler perhaps)

The overall width of the trailer as the current design stands equals the width of my bike - from saddle bag rail to saddle bag rail, roughly 33".

current weight design limitations;

bike hitch (already bought and mounted); 300 lbs towing capacity with a 30 lbs max tongue weight

4" shocks (already bought, same type used for mc seats for example); 300 lb rated spring with a max load of 175 per shock (original design I had only had one shock, current design could be changed back to one shock if needed)

14" street tire; (already bought) 225 lbs load capacity apparently rated to 70 or 75 mph going by text I found online stating "all 2.5 x 14 tires are rated for 70 or 75mph" (shouldn't be a problem at all)

So the gross weight if I understand it right cannot be any more than 225 lbs which also shouldn't be a problem going by early estimates.

Enough rambling for now, I'll add to it as things progress, which should be later this week when I begin working on the "u-joint coupler" I've so named for the hitch connection.

The attached pics were created on a pc. I cheated and found a side profile pic of my bike (tks to moco's website) and created an acad dwg showing the approx profile of the trailer behind the bike. I'll add real pics as this progresses.

I realize this isn't exactly a perrty design by any means...it's just meant to be functional and to get the job done.

Am I thinking too far outside the box? LOL

Re: single wheel trailer "on the cheap"

Posted: Tue Jan 03, 2012 2:55 pm
by ampster
just to clarify a little bit since the pics do not show a completed design, items shown in blue in the screenshots are items that I am still "working on" in terms of a final design. Hard to see, but there are some "legs" I'm thinking of attaching to it that when it's detached from the bike, it just won't tip over LOL. In the screenshots, the legs are currently in the stored position and would pivot or swing down directly below the forward basket.

After I had seen some close up pics of one of those "n-line" single wheel trailers, I added that horizontal blue tube near the hitch that allows me (hopefully) to grasp that blue tube and hold the trailer steady while connecting/disconnecting the trailer to the bike. That feat in itself should always provide someone with some entertainment as I try to connect/disconnect the trailer!

Items I have already purchased;

hitch for bike (already installed on bike)
swing arm + 12mm "pivot" axle (not sure what to call it...the axle the swing arm actually pivots around)
14" street tire, rim, tube, rim strip and 15mm wheel axle
4" shocks
the 3 baskets shown
the only piece of steel I've picked up so far was the 4" long, 2"x2"x1/4" sq tube.

Re: single wheel trailer "on the cheap"

Posted: Tue Jan 03, 2012 5:54 pm
by curt
nice work man looks real intresting hope to see some pics when its completed

Re: single wheel trailer "on the cheap"

Posted: Tue Jan 03, 2012 5:56 pm
by Maz
I have never experimented with a trailer on a solo bike so this is a learning curve for me too.....I'm really interested to see where you go with this dude :popcorn:

Maz xx

Re: single wheel trailer "on the cheap"

Posted: Tue Jan 03, 2012 6:42 pm
by railroad bob
Looks like a nice project...

Couple of quick notes... Consider a fender for the trailer tire, and mounting the spare on the trailer tongue or behind the front basket
You'll want to have a fair amount of weight on the tongue to prevent uplift on the bike's rear wheel. Mounting the spare on the rear might cause the center of weight to be too far back, and it puts it in the path of road spray and debris from the trailer tire.
You can adjust weight with the bags as needed, but you have more flexibility if the tire is forward of the axle.

I like the use of baskets, eliminates considerable trailer weight, and allows multiple attachment points for bungees. Also allows an open area for optional fuel cans. Consider a tarp to wrap or cover the load, even using weatherproof luggage. Sometimes road construction mixed with weather can create muddy conditions, and you won't like opening bags covered in mud to get out your fresh clothes.

Re: single wheel trailer "on the cheap"

Posted: Wed Jan 04, 2012 9:41 am
by ampster
good points bob. I have a fender modeled up and have located a source to make it - just forgot to add it back into the assy model after a recent change. If money was no object, I'd like to get a fender made that looks a bit like the Indian fenders, the way the side of the fender draped down the sides of the wheel.

hehe, yeah I had the spare mounted under the tongue on one of the many design iterations. The actual tongue length/tongue weight hasn't been figured out yet. I could have sworn I read something online to the effect that tongue weight, or the idea that you need tongue weight, doesn't actually factor in with this type of hitch connection. I have not been able to locate where I might have read that however.

Current plans unless I do find some reputable source to state otherwise is we are planning on roughly 20lbs or slightly less tongue weight.

Also, I like your idea of tarps or something to cover the bags up. The bags at Cabalas seem to be made of a thin material and I suspect setting them in a tarp, then into the basket would be better.

Parts came in from McMaster yesterday - mostly stuff for the "u-joint coupler" and some other items for a mobility scooter lift bar I'm working on for my mom. Will be going over to a friends place later this week to start getting accustom to his drill press so by this weekend I'll be ready to start.

real pics by this weekend.

Re: single wheel trailer "on the cheap"

Posted: Wed Jan 04, 2012 11:10 am
by Jeff L
This looks really cool to me, having never seen a single wheel trailer.Is there an advantage other than weight having only 1 wheel?Ill be damned if understand how it doesnt tip over.

Re: single wheel trailer "on the cheap"

Posted: Wed Jan 04, 2012 12:58 pm
by ampster
a couple of reasons I went with this type of trailer Jeff was;

1. when cornering, the trailer leans just like the bike and follows you. From what I've read online, you can't tell it's back there - then again, I read the same story with 2 wheel trailers.

2. Remembering the "you can't tell it's back there" thought...a 2 wheel trailer will be wider than your bike. I've read of a few people who momentarily forgot they were pulling a trailer and hit things in their path. I can very easily see myself forgetting something is back there and sticking out wider than my bike.

I'm also shooting for an extremely light trailer. Early estimates of just the structural steel is coming in at near 30 to 40 lbs. Although I could have also built a two wheeler that would have been light, I opted to go with a narrow design which this trailer provides. If anything, the lights on the trailer might stick out past the width of my bike, no biggy.

You are imagining what would happen if you connect up this trailer to a ball type hitch. You wouldn't go anywhere and the neighbors would get a good laugh!

Now imagine a "u-joint" type hitch. This type of hitch only allows for the trailer to turn left or right and up and down movements, reference attached pic and some more info from this thread if desired;

http://www.choppercompendium.com/ccforu ... f=30&t=190

ps, for those who were following the other posts in that link, you'll notice I modified the "u-joint coupler" in the pic attached to this post to something that I thought would be easier to make out of my garage rather than the part shown in that other post.

I have seen quite a few videos on YouTube of single wheel trailers in action. I can provide links if needed or just search on "single wheel trailer" for example.

Re: single wheel trailer "on the cheap"

Posted: Fri Jan 06, 2012 1:08 am
by concrete guy
Looks pretty slick. I have never seen a 1 wheeler before. I look forward to watching this.

Scott

Re: single wheel trailer "on the cheap"

Posted: Wed Jan 11, 2012 8:12 am
by Groenie
Ahh, finally a topic I can actually add to!

I built one for my KLR a while ago. It mounts (swivels up an down) on an extended rear axle I had made up and can turn from side to side on a vertical joint just ahead of the box. The vertical joint is actually tilted forward by a few degrees to improve handling. It takes way to much luggage, but makes for an excellent beer wagon...

Re: single wheel trailer "on the cheap"

Posted: Wed Jan 11, 2012 2:55 pm
by gww25
Needs to be way bigger for more beer even if you have to get a bigger bike to haul it around.

Re: single wheel trailer "on the cheap"

Posted: Fri Feb 10, 2012 2:56 pm
by ampster
I know I've seen those pics somewhere before Groenie! I bet that makes ppl smile when they see you coming with the beer!

Gary's remark reminded me of the multiple pics I seen where one guy on a ultra classic was pulling what appeared to be a trailer to haul cars on, but it was fully loaded with beer instead! However not one of the pics appeared to show he was actually moving so maybe it was staged.

OK, so going the cheap route isn't always the best!

I'm fighting the tongue weight in my preferred design using a Thule Sidekick car-top carrier (read - yet another design change). The hitch I've already bought for the bike (which was the cheapest I could find) has a 30LBS tongue weight limit.

If I use a static load calc using this for example;

http://www.engineersedge.com/calculator ... vers_3.htm

I'm too close to 30LBS. I'd rather be near 20LBS to feel comfortable. I'd really like to go with the design as shown in this post someway/somehow rather than mount the car top carrier over the wheel. Granted I could cut out a portion of the bottom of the car top carrier and have the wheel plus shock area go up into the carrier a little bit, but still that seems like an ugly design. If you search online for info regarding this type of setup - you'll see all sorts of replies which basically leave you just as confused as when you started searching! Anybody with experience figuring out tongue weight considering this type of design? I'll buy the beer!

Another problem I have is I buy crap left and right before settling down to a specific design and just move forward.

Additional things I have bought besides what I mentioned before;

90% of the raw steel needed for the 1st design shown in this thread which cost a little over $100.00 (mostly for cutting costs, $5.00 per cut so I got a few pieces that are 8 to 9 feet long and I'll cut the final pieces myself), minus the material for the tongue itself plus an odd piece of metric material I might have to beg Maz to send me...hehe...
a used table or small drill press for $30.00 off craigslist (the drill press my friend has, it's for wood and he's missing the drill chuck, besides even if I don't use the drill press for this project - always good to have around)
and just the other night, a "new" Thule Sidekick cargo carrier for $150.00 that has never been used.
And I used BigJim's suggestion (by way of a picture) and bought one of those high-torque u-joints from Mcmaster. That was paid for at least by returning most of the other items I had bought to make a u-joint from scratch.

Soooo, I've got to stop buying crap and settle down to some design and just go with it.

Maz, if you're following this, or anybody that has access to metric tube/pipe, I've got a problem with the "pivot" tube for the swingarm. That's what I am calling the red piece in one of the attached pics.

The swingarm uses a 12mm axle. I've already got the 12mm axle - I'm having a heck of a time trying to find material over here that would be suitable for this.

What is shown in the swingarm-pivot.jpg includes a hole for a zerk fitting. That was one of the options I was hoping for - to find a DOM tube that is close to 12mm ID and use a jerk fitting to keep it lubed up. Can't find anything close enough to 12mm (0.472) ID that I feel comfortable with. I don't have the actual axle diameter handy, but I do recall it was slightly less than 12mm when I measured it.

Another thought is to use an oversized tube there and use some metric oilite bearings (the zerk fitting wouldn't be used with metric oilites). The best I can find is to use a 1" OD x 3/16" wall tube with some metric oilite bearings that have a 16mm OD x 12mm ID - however if I understand what is recommended for a press fit, that's too much at approx 0.005 oversized. Online I found recommendations that for 1" and under press fits, an ideal is 0.001 per inch. Maybe I am not interpreting what I read online correctly?

The last option is to buy a long 12mm drill bit and attempt to drill out something that is well over 4.75 inches long (depending on what material is used) - but that seems like it would be tough to align a tube/pipe in a cheap drill press.

So I am wondering, will it cost an arm and a leg to have someone mail me a 5" long piece of say 20mm to 22mm OD x 12mm ID DOM tube? Actually make it slightly greater than 5" long just to be safe.

On a side note, I found a "double-leg kickstand" on ebay that's rated for large bikes/mc dirt bikes as well. So these pics include a rough representation of that item as well - and no, I have not bought that yet even though it will probably work no matter what design I settle on.

Have a great weekend all!
Steve

Re: single wheel trailer "on the cheap"

Posted: Fri Feb 10, 2012 8:19 pm
by ampster
OK OK, enough of the teaser pics, here's some of the real thang! :banana-gotpics: Well, at least the 14" complete wheel assy with the 2007 kawi swingarm plus both axles.

Looks like I wont have to adjust the wheel spacers at all. The worst pic shows the slots I had milled out to 15mm, not sure if the guy who did that for me was happy about it.

I might have to take the tire off the rim and take more care in balancing it. I noticed there wasn't a mark on the rubber showing where the tire was heavy (or is it light) like normal mc tire manf.'s do. Maybe they don't bother with such a thing on dirt bike tires?!?!?

Re: single wheel trailer "on the cheap"

Posted: Mon Feb 13, 2012 11:19 am
by gearhead1951
If you dont have the shaft you need yet and would still consider bushings for it to ride in , then I suggest you measure a few different shock damper shafts to see what comes closest to what you need (might even find one exactly the right size) and go get that same shock from a scrapyard or auto repair shop and harvest the shaft !

If you can get close enough you can adjust the bushing inner dia. to fit !
:obscene-drinkingcheers:

Re: single wheel trailer "on the cheap"

Posted: Tue Apr 24, 2012 2:34 pm
by ampster
so much for attempting to get this on the road by the time the bike came out of storage! Plans now are to hopefully have something that can be tested on the road by early May.

Usual delays in getting anything done - plans for who could/would do any stage of this changed monthly!

Sorry about quality of pics, they're from a couple of cell phones, I will use a "real" camera for final pics!

Month or so ago we finally got most of the steel cut to length - did so in a friends wood shop using his radial arm saw with a metal cutoff blade.
cutting-steel.jpeg
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Transferred the cut steel over to another friends house and he was able to get most of the carbon steel welded up this past weekend.

Nice and simple "jig" used, a mc lift along with a couple blocks of wood!
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welding2.jpeg
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most of the welding is done is the following pic, just a couple more welds to finish up what is shown
practically-done.jpeg
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been awhile since I've gotten the pics off my cell phone and found one of our 2 yr old G.S. named Cody...never seen such a lazy sitting posture!
lazy.jpeg
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