Amberwolf's Flatbed Kennel Trailer Mk III


Staff member
Aug 17, 2009
Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion
Previous versions are here:
and here:
but now that I've got a second, bigger St Bernard (Yogi), in addition to Tiny, I kinda need a bigger trailer, too. I already needed a tougher one, better able to handle our roads here with heavy loads in it, and beefing up the old one would've been harder than making a new one, so:

This one uses a ball hitch, like a car, cuz I KNOW it will handle the loads, and it wasn't hard. Already had the ball, found on the side of the road. Rebuilt CrazyBike2 a few days ago to fix up problems iwth the bottom cargopod rails, and used that chance to add the hitch platform:



Earlier this week, I started on the trailer, but didn't get past the pondering stages. First I looked at hte old trailer and thought about what to do to make it better, but quickly figured out I couldn't do what I wanted to without so many alterations I could just make a new one and keep this one as it is, for my one (or two) "regular" bikes. :)

One potential issue is tha tif there's any flex in things, the wheel is gonna rub on the kennel:
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but I have some oideas to fix that.

The kennel will come off and go onto the new one, but the rest will still be there as a flatbed trailer for stuff. It shouldn't need a better hitch if I'm using it on a regular bike cuz I couldn't pedal with that much of a load (I often might not be able to do it with NO load).

So, then, I worked out teh basic idea using the bottom frame off an old retail book rack, and some other retail signage tubing, some old BMX forks and wheels (the ones off my original Chariot trailer from DayGlo Avenger, cuz they are 44-spoke and have tough steel rims, though they need new axles and bearings and tubes and tires).
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I wanted to use 16" wheels, to keep teh whole thing close to the ground, but the only ones I have are single-ended axles with "QR" pin axles, and arent' capable of handling the loads I wanted. But if I use 20" wheels and mount the axles a little higher than the frame, it'll put the frame about the same height off ground as it'd've been with 16's mounted axle-thru-frame.

The reason for hte BMX forks is that they will give me doublesided axle support, and will weld easily to the bookrack frame. Unfortunatley I didn't have any pair of identical ones, or any that were beyond "sort of similar". I ended up cutting the dropouts off one 16" kids bike fork, and transplanting them to one of the better 20" BMX forks that was already veyr similar to another 20" BMX fork that was probably by the same maker as the 16".





I used an old axle off some broken cart to align the dropouts of the forks while I welded the do's to the fork.

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Later I did something similar, but with a yardstick and a couple of L-squares, to aling the dropouts and square them with the frame, when welding hte forks to the frame. Theyr'e only tacked on, in case I need tochage sometingh, cuz i have a feeling I might.

To put the forks on the frame, I considered a few ways, including jus twelding along the narrow interface I'd get if I jus tlaid the roound tube on top of the square, but that wouldn't be nearly strong enough for my purposes, I think. So I cut the "inside" leg of each fork in half lengthwise, so that the edges of the tube are aout teh same width as the 1" suare tubing, so when I weld it together it'll be able to more easily transfer load back and forth.
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I also clamped them down (and tackwelded the rod to the dropouts, as it isn't threaded to be able to use nuts to clamp it) so I could anglegrind the whole surface level and flat for the moutning edges of the forks. This took at least an hour to do:

It won't be perfect, cuz the forks can't go on there straight cuz they are not a perfect U, but have outward splayed dropout ends vs the U part. Not by much, but enough that if I want the wheels to track straight and not have toe-in and scrub, then they'll be slightly diagonal across the frame.


I may also use another pair of forks, welded vertically to the dropuut end of these forks, as an extra verticla stiffener. The reason I didn't moutn these forks like that in the first place is I also wanted "brush guards" so tha tI don't hit anyting with the wheels themselves, for stuff tha tstick out into the road that I may not be able to avoid when in traffic, or on narrow bike paths that simply don't have the room for a wide trailer, with all the plants/bushes/etc that grow unchecked along the path in some places.

I may also add fenders later, too.

One thing I did find already was that the droupouts on the left-as-is fork are quite a bit narrower spacing than the ones on the other. I don't know why I assumed they were the same width but I did, so now I have ot cut them off that fork and reweld them at the correct width to fit hte wheels I have. (I can force a wheel in there but I don't wnat to have to do that on the side of the road if I ever ahve a flat or other wheel problem).


FWIW, by the time I got done with all this stuff, I probably coudl've just made the wheel mounts form scratch, but I didn't consider that when I started, and I'd already done all this work by the time I did thikn of it. :oops: Maybe next time. :)

I haven't got any farther yet, as I was bugged by mosquitos all day from dawn thru well after noon when I finally had to give up and stop to get something to eat, etc.




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More thoughts and pics, not a lot of progress yet. I have a decision to make, and that's holding me up (along with all the extra time used up on rebuilding CrazyBike2
here, which has taken almost all of my vacation time).

BTW: one reason I am opting for lower to the ground rathe rthan wider, is that even an existing kids' trailer won't even fit thru the back door, and barely fits thru the front. :( So if I make this any wider than that, it would have to stay outdoors all the time, and never come in with me at all no matter where I am or go, and that might be a problem someday. :(
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The trailer frame is almost exacly three bricks off the ground, and the hitch on CB2 is another 2 bricks above that. So either i need to move the bike's hitch down, or I have to put the tongue on the trailer up higher than it's frame. I think it'd be stronger to have the trailer one flat plane of stuff, instead of haivng to go up in an L and reinforce it with braces and such.

But redoing the stuff on teh bike isn't trivial, either, and *it* is stronger where it is, because it is part of the lower cargo pod rails this way. If I move it down, it'll then be able to push the bottoms of the pods themselves to the sides against hte rails, which it couldn't do now. I don't know how that will affect the bike. Presently the hitch point is *just* above the rear axle height, and several inches behind the rear tire's back edge. It'd have to be several inches *below* axle height to enalbe the trailerframe to be a single plane.

EDIT: Also, I'm unsure if I should put hte cargo space behind or in front of the kennel part. If I put the space behind it, then I have to add a rear vertical frame or post both to hold all the lights and stuff, and another SMV sign, as well as to strap things to. If I put it in front of the kennel, I get more space cuz I can also use the A-frame of the tongue to strap to, but it will block the kennel door, which needs to point forward cuz I would like the dogs to see me and where they are going (even though it means the trailer is a giant airscoop that way). I can also then make a curved "clear" cover to put from the A-frame to the top of the kennel, to alleviate that scoop somewhat. There's pics below showing both options.

I need ot make up my mind, so if anyone has any experienced input on hitches and hitch points for heavy-haul trailers, I'd appreciate it. :)


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Short of any replies about the hitch, and needing to make *something* to use so I can work on carting the dogs around now that the weather is cool enough, I went ahead with the "L" going up from the trailer frame to the hitch ball on the bike.


I still have two angled braces to add, but I tested it with 285lbs of bricks and old SLA tossed randomly into the kennel, and rode more roughly with it than I would with dogs in there, and didn't break anything, though the load shifted a few times. (had to measure two fo the SLA separately, cuz the scale doesnt' go that high!)

The trailer itself at this point weighs around 55lbs, not including the lights and wiring, hitch lock and security cable (just in case something happens to the hitch, it ties the frame to the bike's frame), which all together are probably a couple more pounds.


The hitch tongue is bolted thru the top of the trailer tongue, and also spot welded at it's rear corners. I messed up on making the trailer tongue, though: I marked and cut the side angled pieces so they'd go past the 45-degree brace under the tongue, but somehow I managed to cut them about two inches shorter than I marked them, and I don't understand how I did that. :roll: Well, anyway it dosn't matter cuz I am still gonna add a 1/2" square tubing brace down form the rear end of each of those tongue-sides, to the front corners of the frame itself, ot minimize any side-to-side wiggle of the tongue vs frame.
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The major issue with haivng the tongue go up from teh trailer is that the door to the kennel only opens partway: it's more than enough for either dog to easily go in or out, but it's a little annoying. I tried to figure out a way to keep it strong and to leave the door clearance, but no matter which way I did it (even at a 45 degree angle instead of direclty upright) it'd still stop the door right at that point, unless I had it straight out from the front of the trailer. That won't work easily cuz of clearnace issues with the bike itself, so, I left it like this:

However, despite it not having any detectable issues with the wheels/etc during or after the test run, I found that if I accidentally drop the trailer on a wheel (which happened as I let it down from the hitch point I stood it on the scale with), it'll bend the U-fork right good, sending the wheel canting inward at the bottom by a LOT. It did not affect the wheel itself, so I guess I tensioned it right. :)

So to prevent that, or minimize it, I'm gonna have to add the vertical U over the top of the wheel at the dropouts, as I had pondered in the OP. At least I found out now, instead of on the road with a load (like the dogs) in it.

Speaking of wheels, I siad before these were steel rims, but they are not: they are aluminum, doublewall, actually, and are 48 spoke not 44. Thy're the old BMX wheels I originally used on the "chariot" trailer I built for DayGlo Avenger, and sat unused for a few years now, since I made the other flatbed kennel trailer MkI. I don't remember the spoke tension being almost zero, but when I started working on the wheels to replace the bearings (some of which were damaged, along wiht one of hte axles, in a bearing-cap failure on the chariot trailer), I found many spokes so loose they rattled around. Rims weren't bent, so ti was just lack of tension.

After replacing all the bearings (and regreasing) and the axles and nuts with ones off other old wheels I won't be reusing as wheels, I tightened them up, and trued the rims, so they should be good for a while now.
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I also notched the kennel itself, so it fits down into and latches onto the frame. Now it does not have to be bolted on at all, and will be removable when empty if I need to make it into a flatbed, much easier than unbolting it. It also sits much lower on the frame, so combined with the lower frame itself, it lowers the entire COG of my loaded trailer, *and* it brings the top of the kennel down way below the lighting bar on teh bakc of the bike's seat, so youc an clearly see the brake, tail, and turn signals on the bike, too, from any vehicle that's behind my conglomeration. :)

I added a brace under the front of the kennel so it can't sink down between the frame, too. It goes down in a squared-off-U between the forks, and also serves as an extra brace for the frame at the wheels. I was gonna stick it under the front edge so it also cannot possibly slide forward, but that didnt' work out, as it would keep me from sliding it forward to take it out of the frame, too.

I still have to make a flatbed cover for the frame that "latches" on, but that's not that big a priority yet, as I usually use it for the dogs or use it with teh kennel as a locking cargo container.

I also still have to make a rear mounting bracket for all the lights, and an SMV sign (which I also sitll have to get, or maybe just move the one I have on the bike to the trailer when I am using it); for now they are ziptied to the back of the kennel itself.
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To connect the trailer lights to the bike, I used a 5-pin DIN, like MIDI cables or the old AT-style keyboards used. (mostly because it has enough wires for tail, brake, and L/R turn signals, and because I already had the mating ends on DGA from the old trailer). I'ts not waterproof or anything, but it is fairly durable and takes a fair bit of plug cycles ok.

The lights themselves are the ones off the back of Delta Tripper, but with the incandescents in teh turn signals replaced with LED units intended for a Fluval aquarium (to replace little 12V MR-style halogens). If they hadn't been clearance cheap they'd've cost way too much to use for this, but I got four, and eventually they will go on the actual bike itself, when I get to it's rewiring. The paper towels jus tkeep the bulbs from shifting around under vibration.

Oh, and performance of the bike pulling that 340lb load: 69.4Wh/mile! :lol:
Yeah, it sucks but it can do it! :)

Takes like 10+ seconds to reach 20MPH from a stop, vs 3-3.5 seconds with just the bike.

Actually got higher regen currents than usual (double what I typically see on my commute); I wonder if that was because it was being pushed harder from behind while braking?


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Crossposted to the CrazyBike2 thread, cuz it's an interactive problem:
I may have to modify the hitch ball placement. Sometimes when the road crown is steep (not often around here) or on certain turns into driveways, etc. I can feel the unloaded trailer dragging the back end of the bike a little--not acutally moving the tire but trying to tilt the bike slightly. If it was loaded it'd probably be significant.

I can't actually see the trailer completley while riding, just a little with my mirrors, but I *thinK* that it is tipping onto one wheel when this happens. That would likely not happen if it was loaded, and instead would tilt the bike by force/leverage, and/or twist the trailer tongue (which can still happen now, but won't be able to really once I add the angled bars on that).

The problem appears to be that the edges of the hitch tongue are hitting the bottom fo the ball and/or the rear of the hitch plate itself, at certain bike vs trailer angles and leans of the bike, and this is causing roll torque thru the tongue.

The two main possible solutions are:
A--Raise the trailer tongue up a couple of inches, and angle it downward
B--bend the biek's hitch ball platform downward at the rear, so it is either flat or actually angled down at the back a little bit.

A secondary solution might be to trim some of the edges of the hitch tongue itself, but I don't want to do that unless nothing else works (even though it's already stronger than I need, by about quadruple or more since it's rated for 2000lbs), I'd rather have that safety factor).

Solution B is the most likely to be relatively easy to do. I'd just have to slice from beneath into the square tubing that is the extension of lower cargo rails to make the hitch platform, not all the way thru them, just from bottom thru the sidewalls and leave the top intact. Then bend the platform downward by however much this will allow, and reweld that cut closed. It should be just about as strong as before, that way, but now at a flatter angle, and reduce or eliminate the problem.

FWIW, if this was on a trike that didn't lean, like Delta Tripper, I don't think there would be a problem, or at least not as much.
I finally got a video uplaoded of the side-to-side wiggle on the trailer wheels:

The problem shoudl be fixed by the vertical U fork addtion, as well as the over-top-of-kennel frame piece, once I get that far.
Haven't got the wheel issue fixed yet, but I got the lights mounted on a T bar at the back end, so they'll be separate from the plastic kennel, allowing me to remove the kennel for other cargo needing a flatbed or whatever, and also allowing me to move the lights from this trailer to the much wider version I will eventually make. The light bar has a spot weld to secure it for the moment, but it also has a quick-release button on a post that goes down into the vertical of the T. That will become a bolt later. The light bar is setup so that it stops just below the lip of hte plastic kennel, so I don't have to put it any farther back or modify the kennel any further.
I tidied up the wiring after taking the pic....

This is the weld of the vertical to the back of the trailer frame itself. It might later need a V=brace or something, but most likely it'll be fine.

The other thing I got done was to add the A-frame angles to the tongue, so it's braced both sideways and vertically. Should help with heavier loads, or wiggly ones. ;)

The welding is much crappier on this part, cuz I used the little 115VAC HF welder instead of the bigger and better HF 230VAC one, cuz I hurt more today and didn't feel like lugging all the stuff for the big one out and running it's heavy long cord from backyard into house into utility room to dryer outlet.... (if I ever get the sheds setup for working on bikes I won't need to worry about lugging things around like that, cuz they'll all be in the right place to do the work to start with).

I still need to fix the hitch on the bike itself, so that it is angled down in back, or at least is flat (is presently slightly angled upward). I'd rather use the big welder for that job so I didnt bother with it yet.
About halfway thru lacing an X5304 motor into a 20" rim for another project, Bill showed up so we could go to lunch, goodwill, etc. At GW i found this BMX with 68-spoke 20" wheels, which should be great for the second larger trailer that's to be built aolong the lines of this trailer.

The larger one will be meant to haul both Tiny and Yogi at the same time, so it has to be wider, and it'd be nice if it's wheels were really strong, too. I think these should do it. :)

They do need tob e tensioned, but the rims are true jsut as they are, which is a good start. AFAICT they are singlewall alloy rims, so they may not be as strong as the double wall rims on my 48spoke wheels on this present version fo teh trailer.


Maybe with more spokes it won't matter as much? Eithe rwya, they're still better than any 20" wheels I've already got around here.

The tires are not in great shape, tread worn off the middle, and are thin to start with, but if I use some of the other old otherwise-unusable 20" tires in there as "liners", and use thick tubes, I think they'll do ok for a while, at least for testing purposes.

Not sure what I'll do with the frame itself yet, but it is almos tidentical to the one I cut the droputs off of to weld onto CrazYBike2's rear--those are still doing fine service for the HSR3548 it's got now.

For the mometn I'm using the frame's rear dropouts (stillatached) to test the X5304 in as high a load/current/etc as I can put on it, prior to putting it on CB2 to test it.

Anywya, I really only cared about th wheels on this BMX, to be used on the trailer. Plus, if I need to, it also has a threaded-on singlespeed freewheel on it's rear wheel, that I coudl use to drive whichever side it ends up on as an assist to pulling things.

(it is pretty likely that I'll want an assist for it eventually, as the larger trailer will also make it possible ot use as a flatbed to haul really heavy / bulky things, and it'd be nice to take some of the load off the motors of the bike itself)
amberwolf said:
Oh, and performance of the bike pulling that 340lb load: 69.4Wh/mile! :lol:

Holy Winnebiko! A dog that big should be pulling the bike :wink:

Nice use of available materials.

I've seen trailer hitches that have a sliding action that allows brakes to be applied anytime the trailer tries to push the tow vehicle. Otherwise you might want to stay away from steep hills.
fechter said:
Holy Winnebiko! A dog that big should be pulling the bike :wink:
Yeah, well, that was just a bunch of bricks (building and SLA type), but it is possible that I might load down this trailer or it's larger cousin-to-be with that much weight, either with both dogs (~230lbs together, Tiny=100lbs Yogi=130lbs) plus supplies, extra batteries, etc., or as just a cargo trailer carrying a bunch of whatever.

If I did have a single dog that big, I probalby woudl've built a dog-pulled rickshaw by now! :lol:

(or just put a saddle on it!)

Nice use of available materials.
Thanks--I kinda have to as much as I can. Not enough $$ to do otherwise, though sometimes I spend some on something like that BMX for it's wheels, when I know I can't build anything better with what I have already, or buy the parts to do it for htat.

I've seen trailer hitches that have a sliding action that allows brakes to be applied anytime the trailer tries to push the tow vehicle. Otherwise you might want to stay away from steep hills.
Thankfully we don' thave much in the way of hills of anykind around here; I probably would avoid them with a loaded trailer anyway just becuase the power requirements could be huge to haul up the hill.

I suppose I could figure out a torque sensor of some type that would sense when the trailer is pushing on the bike and autobrake. Maybe using something out of an electronic scale?

Might be easier just to use as you say a sliding type of hitch (maybe using long slots for the bolts that hold the hitch tongue part to the trailer tongue, and something like teflon washers and plates between the bolts and the tongue parts so they can slide easily?), and a mechanical switch

Eventually those could be sealed microswitches, etc to engage and release e-brakes on the wheels, when I get them powered, eventually.

At first, though, they coudl just be regular bike brakes setup so that the sliding action pulls the brake cable thru a pulley....

That actually sounds really easy to set up (though it probably wont' be nearly as easy to get it to work like I want).

A bit of googling finds these commonly called Surge Brakes, like here:

As they point out there (and I hadn't htought of yet), I wouldn't be able to back up wihtout a mechanical override of the brakes, so I could put a cable-operated or solenoid-operated latch on them, that would be run from the trailer up to a point on the bike somewhere, to let me override the brakes when necessary. Maybe an old friction shifter for derailer to control it with? One that clamps on the downtube would be really easy to undo and redo, and it could clamp on in a number of places and still be in easy reach.
The industrial strength ones use a hydraulic cylinder on the hitch to engage the brakes. I was thinking more like pulling on a cable for caliper brakes. Probably not worth the complexity if you don't need them. You could also just run a really long bike brake cable to the handlebars and be able to apply trailer brakes that way.

Now, if the trailer had hub motors....
Eventually, it will have an assist of some type; I don't know what. Depends on how things evolve. I don't think I haeve any two identical hubmotors, unless the Amped MXUS rear DD I have happens to be the same wind as the Ebikekit 9C 2807. (assuming that both can be fixed; I think it's bad halls).

Anyway, cable-operated is how I'd go, and I have pondered how to do automatic brakes, but the only ones I could think of would be regen on motors, unitl you suggested the surge brakes--THAT makes everythign relatively easy, even using cable instead of hydraulic.

I definitely do need brakes on the trailer, cuz with a heavy load while the bike *can* stop it, it takes longer and farther to do it, and it's a lot harder on teh bike's brakes when it does.

I originally was just going to run a manual brake cable up to the bars, but I would have to figure out how to "clip it in" to the existing brake line, as I have no place for *another* brake handle that I can easily squeeze at the same time as the bike's, and I have no idea where my dual-brake-cable handle is that AussieJester sent me ages ago, after all the mixups and disappearances of stuff during the cleanup after the fire.

Surge-style autobraking, if I can set it up right, should be the solution. (it also means I can very easily put the trailer on and off, no cabling or adjusting needed, other than whatever I use for an override to back up, and whatever I have for lighting wiring).
I found the dual-brake lever from AussieJester, and my dual-brake cables off some old BMX bikes.

The former probably wont' get used fro the trailer, but the latter will be essential for setting up both rear brakes to run off one cable, and adjusting them to pull the same.

I won't be doing any surge brake inventing for a while yet, but they'll work for that, too.


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I've never seen a dual pull lever like that. Seems like it will be perfect. It would be nice if there was a simple quick disconnect for the cable near the hitch. I can't think of something simple right now.
Apparently there are a few:

and they do all look fairly simple, though I dont know if I can make one as small and nice as the ones here:
Many seem to be only intended to go on bare cable stretches, not between housings (which is where mine would probably have to go, as I have no cable stops anywhere on my frames yet).
The hydraulic ones are cool.

I see. You'd need some kind of bracket to hold the cable sheath on both sides of the connection.
Yeah. Most likely I'd just have to put cable stops on bike frame by the hitch, maybe directly under the hitch ball, and another on the trailer tongue frame, in the same area, and use that stretch of unhoused cable to do the coupling. (would rather do it on top but I don't see an easy way without adding a frame piece over the hitch, and that could get in the way of other stuff.
First ride in teh trailer for Yogi, up to my workplace to meet people and get him used to the idea of the ride.

When I was still getting him out of teh trailer and setup on leash, I had someone come over to ask if she could take a picture of the bike.

I also had a bunch of poeple just exiting the store wondering about the trailer until Yogi barked at them, while he was still inside it. A couple of them jumped back, even though they were already about 20 feet away (he's a little on the loud side, with those big lungs of his).

He had some fun with the whole deal, but he wasn't all that happy about getting back into the trailer afterward, though he was definitely ready to go home.


As you can see in that pic, there's a steel (orange) cable securing the trailer to the bike (just in case something should happen to the hitch itself).

One interesting problem I hadn't foreseen was that even with Yogi's weigth in it, the kennel itself slid forward on big bumps, and would if unchecked come out of the retaining bars on the trailer frame. :( That woudl be bad.

So I'll need to come up with some sort of retainer for it. Bolts thru teh sides of teh bottom half would work, but I'd like something that takes care of the whole thing. So most likley it'll be part of the bar that still needs to be installed over teh top of the kennel, which will be to stiffen the forks up.

Speaking of that, I didn't get any shifting of those, or rubbign on the kennel, even with his weight and the potholes, bumps, etc., and him sometimes shifting around to watch things on teh roads and around us. So it may not be strictly necessary to do the reinforcement, but I will do it anyway, since the results of a failure could be pretty serious.

I'm thinking that I am probably gonna make a little detachable cargo rail frame around the top of the whole kennel, using 1/2" square tubing. It will both secure the kennel to the trailer (even in the unlikely event of a rollover) and provide a place to strap stuff down when used as a cargo trailer with or without the kennel on there.

The ride was actually easier than with it unloaded, since the trailer didn't slew around corners, but smoothly traversed them. I could feel it back there, with his 130lbs added to the trailer's own weight, but it didn't rpesent a problem, even up to 20MPH. Mostly I stayd around 17-18MPH, as it "felt" best around there.

Braking distance is longer, and acceleration is slower, but that's to be expected. Once I get the surge brakes designed and installed, that'll help a lot with braking. If I end up fully lacing that X5304 and permanently mounting it on the bike, it may help the accelration, too.

I figure once I get this trailer proven and bugs worked out, I'll make the wider version for the pair of them together. :)
Between loctite on the bolt threads and inside the hitch ball, and not passing the bolt thru the lower tail/brakelight mounting plastic, it seems to have fixed the problem of the ball wiggling loose. I expect the plastic in there was the real problem, because:

-- There isn't really enough space to properly get a socket or wrench on the bolt head, to fully tighten it, inside the plastic housing of that light.

-- as the hitch of the loaded trailer pulls back and forth on the ball during braking and acceleration, it could allow some compression in the plastic (acting as a kind of spacer in this instance), which could then allow vibration/etc to slightly turn the bolt or the hitch, eventually loosening it noticeably.

Without the light's housing in the way it can be fully tightened, and it doesnt' have any space to move around in to loosen. So I probably won't need to weld it on.

I still havent' actually cut the cable down to a short length, and added the loop-bolts onto it to make it easy and quick to stick the cable on there, but it does definitely still hold the trailer on even without being on the ball (I tested it via leaving it completely unconnected to the ball, nose of hitch sitting behind it, with only the cable connecting them, and hauled a load of stuff around rough areas and did lots of stops and starts, and while it wasn't nearly as controllable as with it on hte hithc ball, it stays on and doesn't quite hit the ground. It DOES hit anything that sticks up, or if I go up or down a driveway, or some of the potholes that let the rear wheel go down more than a small portion of an inch.) Am still searchng for those loop-bolts (essentialy small U-bolts with hardware to clamp a cable to itself), in my stuff in the sheds.

I haven't made a front-end retainer for the kennel yet; still considering possible options, since I may not even need it if I add that top "roll bar" / cargo strapdown frame / side-load stiffener.

But so far there've been no other unexpected issues with the trailer for loads live or not.
I've used the trailer for a few kinds of loads now, light, heavy, bulky, oddshaped, etc., and the dogs a couple more times (one at a time).

At some point this year I welded the hitch ball to the plate, to ensure no loosening could happen, though the bolt is still there to help ensure it stays on the plate, since it's not a full bead all the way round it's base, just short sections.

No issues iwth that at all so far.

So far it's done well, though two problems cropped up.

The right turn signal has a loose wire, most likely where it is soldered to the pin on the bulb itself, since those pins I think are steel (can't remember). Sometimes it works and somtimes it doesn't, and thte wire chekcs ok all the way up to the fixture. If I pull the bulb out (it was gorilla-glued in to make sure it stays pointing straight), ti sort of works all the time, at varying brightnesses. Gotta get that fixed, but have been too tired to deal with it so far. Since the main bike turn signal is up higher than even the kennel top on the trailer, it's not much of an issue really, as if you can't see that one, you sure wouldnt' see the trailer one even if ti was working fine, because you'd have to be completely blind. :lol:

The other problem is just wierd.

I've never adjusted or modified the hitch tongue in any way, where it clamps onto the ball.

But the time before last, when I took a load of dog food home in the kennel, I had a hard time getting the latch to release, and practically had to pry it off the ball. Nothing bent or even was marked,b ut I didnt' investigate the problme until yesterday when I had to take an old cart-shelf home from work (they were tossing it out, and I asked and got permission to take it home for my own use in the house).

Before heading to work with it, when I tried to put the hitch on the ball, it would NOT latch--I couldn't even get it to start latching.

After several minutes of frustration staring at and moving things around it to figure out what it might be, I thought perhaps the bolt that holds the spring and latch and whatnot all together was somehow hitting the plate when latching it, cuz it was scraping the paint there and had never done that before. I could see no signs of bending, shifting, etc. so I couldn't figure out how it could happen with no changes to the system.

Anyway, I was in a rush, so I got the grinder out and took off about 3-4mm off the end of the bolt. Absoltuly no change to te problme.

So I pondered and stared and rattled things around and eventually realized that the problme wans't the lenght of hte bolt, but where the nylock nut was on the bolt--somehow, it had been screwed almost half an inch up on the bolt, and so it was making the latch pull up the spring and clamp inside even when the hitch was just set on the ball, so it couldn't be moved any farther.

That made NO sense at all how it could get that way, though.

It's impossible to reach the nut with any tool while it's hitched up, because the clamp is around it, and the hitch plate on the bike is right up against it, and since I padlock the latch shut, it coudln't be taken off the bike to mess with it, either.

I hadn't messed with it, and no one else could have messed with it, and it's a nylock nut, so there should be no way for it to have moved up or down that bolt. Yet, it did, and it did it sometime between when I put the trailer on the previous time I used it, and my arrival back at home that night, because it went on normally that day, and was hard to remove that night where it never was before.

Anyway...however it got misadjusted, I fixed it and headed off to work....though now the nut doesn't have enough bolt to fully engage all it's threads, because I ground some off before I actually figured out what the problem was. :(

And I can't trust that the nut will stay in place, either, because of this whole issue. I don't see how it could be sabotage, so I have to believe that it self-adjusted and will do so again for reasons I can't understand.

So I've gotta take the hitch tongue apart, and find a replacement bolt and nut to use on there, out of my junk stuff, and loctite or superglue or whatever that nut on there once it's adjusted, so I can trust it can't selfadjust like that ever again.

(lockwashers of any kind are pointless because the nut doesn't push against any surface for them to work against, except when it's latched onto the bike).

I have made zero progress on the doublewide trailer for both dogs at once (and larger items). Been so wiped out the last several weeks it's been hard to motivate doing ANYTHING I don't absolutely have to, that can't be done from the bed here, like posting to the dayjob isn't helping either, with more and more stress added on week after week with pointless changes that only make things harder for everyone (and some especially harder for me).

No progress on the brakes or anything else, either.
Since the above post, I've built (with Dogman's inspiration and help) a trike, the SB Cruiser, to carry the original kennel crate from this trailer, and installed a very slightly larger kennel crate onto this trailer.

Thus, I odn't need a doublewide trailer to carry both dogs (though it might be nice to build one anyway eventually for wide cargo or to use with CrazyBike2.

(though...I've now been asked about taking in a third dog, riht after adding the abilyt to move two dogs).

It did take me until now, though, to get a trailer hitch installed on the trike to actually haul both dogs at once.

then a few days more to get the lights wired up, etc.

Still gotta get white paint to lighten up the trailer kennel crate color, though, and red to redo the welded areas. visibility and all

some pics out of the two posts about it in the other thread. text details are in those posts.














While doing some painting on the tirke,
I got a chance to do a bit of painting on the trailer, though I did'n't hae enough white to cover the kennel, it does at least make it a lot lighter in color, more visible than ti was before. (and a bit cooler in sunlight, hopefully).
This trailer will still stick around and be used and improved over time, but I'm now building a new one specifically for Yogi (this was built for Tiny for use with CrazyBIke2, and adapted to Yogi when TIny could then ride in the SB Cruiser trike).

So, Mk IV is here:
Tomorrow I'm going to revive this trailer (which hasnt' been used in a while) to carry some of a big grocery load. I expect 2-4 hours to do the work, don't want to waste any more than that on this as it still wont' see that much use, but really needs these upgrades to be usefully reliable.

The over-top-of-load "arch" to keep the wheels from leaning inward will be added, with a rack on top for more stuff without crushing the plastic dog kennel, with cargo strap tiedown points. It'll have at least two "arches", one at the front of the horizontal forks, one at teh rear, both on the outboard side of the wheel.

A third on the inboard side if possible, to add tabs to the arch at the middle 'ridge" area of the kennel so I can bolt the kennel directly to the tabs rather than just cargostrapping it down.

If I can get them on the rims I'll put the old Shinko moped tires (which while worn are still useful) onto the old BMX wheels the trailer has, with some old thicker dead tubes slit and used as liners between the tire and the actual tubes I'll be using in there.

Will post back after the trip with results and performance, and pics of whatever I actually get done on the trailer.
Didn't get pics yet, too wiped out, but the trailer worked, and carried over 200lbs of groceries and stuff without problems (except one).

The only problem was that even with cargo straps securing the plastic dog kennel to the frame, the kennel kept sliding forward, even when empty, so the center "ridge" would rub on the tires. That's always been a problem with this design, and was why I wanted to build the support frame around it with tabs to bolt the kennel to.

But I didn't end up buidling the frame, because I ran out of time and needed to get to the store before they closed (since it can take me a couple of hours to get around the store pushing the cart, especially as it gets toward full, now that I have to be extra careful to not screw up my SI joint again, along with all my other aches and pains).

However, I didn't end up having the usual problem wiht the wheels tilting inward and rubbing on the kennel's sides (not the ridge over the tires).

Probably this is becuase I used different wheels. PReviously I'd used BMX front wheels (since the mounts used to be BMX front forks) and I think they were 9mm (or thinner?) axles. They didn't bend (permanently) but perhaps they flexed or deformed enough to allow this, because even with Tiny, at only 100lbs, or small amounts of groceries/etc (less than 50lbs) I'd still have the problem.

This time I redid the wheels, since the old wheels were rusty (the nuts were rusted onto one axle pretty badly), steel rims, rusty bearings, etc., as I havent' used it in at least 2-3 years I guess, other than to carry tools, cuttings, etc around behind the trike when doing yard work both in the yard and on the street sides of the yard, every few months at best.

INstead, I used two wheels I'd saved around a decade ago from an old jogging stroller; I'd meant to use them to build a delta recumbent something like the KMX (Tornado?)but with suspension, but never even finished designing it, after several life interruptions and then the housefire it just got forgotten. Pretty sure I'll never do it at this point. Guess I probably spent an hour getting the wheels, since I can't move heavy things that are in the way I had to move small things to get to them a different way.

The stroller had been rated for at least 100lbs, and that limited only because it used these as single ended axles (even though they are long enough to use on a BMX fork as double-ended). They're asymmetrically laced, dished almost flat on the short axle (outboard) side, and almost normally angled on the long axle (inboard) side. Didn't really want that but they are what they are. The long axle required two axle nuts as spacers between the bearing face and the dropout inner face, for the inboard side, and the short axle just needed a thick axle washer. This left exactly enough axle to completely thread and tigthen nromal axle nuts on.

The axles are thicker, whatever a normal rear axle would be (10mm? I forget), and the bearings are sealed cartridge types, still clean and low-friction (free spinning on the end of my finger) on the inner sides inside the hub, despite sitting out in the weather basically since the housefire six and a half years ago.

Alloy singlewall rims (FEMCO, Taiwan), brass nipples and stainless 15g spokes. WOuld prefer doulbewall with eyelets, but I don't have any 20" ones that are except those in use on the trike (and the two impact-damaged ones, one of which can't be reused). Don't remember how wide, but pretty typical for older small rims, maybe an inch, inch and a quarter at most?

Just barely managed to get the old Shinkos on them, coudln't use the bike tire levers (they'd just break), had to use wide steel screwdrivers of good quality (HF ones just bent) as I don't yet have metal levers. Took over an hour just to mount them. But they do fit, though I actually had to cut out about a foot of the kennel's circumferential "ridge" where the clamshell halves bolt together, right where the top of the tire goes, cuz they're too tall to fit under it. :lol:

Tires also rubbed on the inner curve of the outboard fork leg at the front, so I had to re-dish them a few mm toward the inboard side. That was a PITA and took over 3 hours because my hands just hurt too much to do it more than a couple minutes at a time.

ONce I was done with that, I replaced all the wingnut stuff on the kennel holding it together, and holding hte grates on (there for the dogs to look out and have ventilation), cuz some of that is old plastic stuff, and all of it is too easy for someone to undo by hand, so replace dthem with nuts and bolts and lockwashers. Maybe an hour or more used up.

Unbolted the lighting bar from the Mk IV.5 trailer, and it's wiring, and moved it to this one. (I actualy have new lighting for that other trailer, the giant wide piano-carring dually one, but haven't gotten it built into a mountable unit or wired up). Another hour or so.... tomorrow at some point, but the trailer works well enough (other than the kennel sliding forward issue) and carries a lot more than it ever had been able to before. It also rides MUCH better with the much larger/fatter Shinko moped tires than any of the BMX / etc tires I've had available to try before. Still not as good as the bigger trailer with the suspended-deck mounts from 26" tires, but unless I rebuild this trailer to work like that one, it's as good as it's going to get.

So it's a useful narrow (trike-width) trailer, with a bit more work someday to fix the one issue.