PatrickGSR94

I use a stripped down InStep trailer with a piece of plywood and big storage box attached to haul groceries by bike. The weight limit of the trailer is advertised as 100 pounds, but I'm fairly certain that the box loaded to the brim does not approach that amount. It's probably in the 50-70 pound range.



This past weekend I was hauling my load back home with my custom-built upright steel utility bike. Due to the way the frame is made, I had to make a "bracket" that drops the trailer hitch down below the actual dropout. I always try to make sure that the QR skewer is very tight to keep the whole thing in place.





I've been using this setup since the spring, and have never had and problems until this past Saturday. This time I was heading across a bridge in a park, and there's a bit of a bump a couple inches tall at the start of the bridge. I pedaled in low gear up/across the bump, then when I got past the bridge I starting hearing an odd noise from the bike's rear wheel. I hopped off to see that the rear wheel axle had come out of the drop-outs! I disconnected the trailer, got the rear wheel back in place, hooked the trailer back up, and continued on home. Seemed to be no problems.

I rode the bike again yesterday, without the trailer, and again there seems to be no problems. I hope I didn't wreck the frame or anything else. Disc brake seems okay, disc still seems to be in good alignment with the caliper and everything else.

I like how the addition of the steel bracket makes the trailer more level since it only has 16" wheels. But I'm not sure I like how it puts a torque load on the dropout when pulling it. I'm wondering if the spring on the trailer arm will break one of these days, also. This bike is slated to have mid-drive e-assist added when I get the funds together, so I'm thinking I may have to re-think the trailer situation, or maybe come up with a stronger way to attach to the frame instead of the wheel dropout or something. Any thoughts?

Darth_Firebolt

I've pulled my 70 pound pitbull in her trailer a few times and never had a problem, even with her wiggling all over the place to see sights and smell scents.

Get a Shimano QR with an internal clamping mechanism. That's the first thing you need to do. Never pull a trailer without one. Those external cam action limp noodles should be illegal.

You might also rotate your QR lever to 2 or 3 o clock so there's no chance of the strap tugging at it. That's about all I can think of.

PatrickGSR94

I now usually put the backup strap through the little triangle in the frame near the dropout. It can't really move forward enough to catch the QR handle. I actually do have Shimano internal cam skewers on my much lighter gravel grinder bike. I might swap them around.

fietsbob

No, No Pull out,
I have a Burly Co Op made Flatbed, and their earlier Alternative combined QR - Hitch.
It does have the safety strap too..

and a Carry Freedom City with a Chariot ball and socket hitch.. its on my Brompton.

Reynolds 

I'd add a brace to to that bracket, from the screw holding the hitch to the chainstay, like a coaster brake arm.

FBinNY 

Take a look at the wheel attachment arm and the dropout.

I can't be sure from the photo, but suspect that there's interference between the arm and dropout. Ideally you'd want the arm to be roughly horizontal so the load when pulling the trailer is straight on rather than on a tangent which would torque the arm.

I gather that you cant have the arm horizontal because of the shape of the dropout, which sets up the problem. When the arm is pulled back, it wants to rotate, band levers against the dropout, pushing the axle down and freeing the wheel.

Prevent this issue by using a longer skewer (if one exists) and a spacer to fill the dropout so the arm can be fitted pointing backward. If that's not possible, you need to fins someplace on the chainstay to attach a brace to the end of the arm and counter the torque the trailer produces.

PatrickGSR94

Yeah I like that idea. Need to see if I can come up with something hopefully without welding.

I wonder if there's a way to rig up a different type of hitch attachment, and get rid of the spring on the trailer, without switching to an entirely different trailer. I like the idea of a ball/socket type of attachment, which shouldn't have the possibility of breaking from fatigue like the spring on this trailer might do, since the spring is bent all the time when moving forward in a straight line.

PatrickGSR94

I'm not sure I follow what you're thinking of.

PatrickGSR94

Yeah I know that, just wasn't following what you were saying about "cut down to fit the mounts on the ends". Were you referring to Reynolds' idea of the brace similar to a coaster brake torque arm?

fietsbob

I go back to I Dont have your frame or Your trailer

and I have never had a problem with My trailer causing My rear wheel coming out

Further consideration.. [post coffee]

Im guessing You have too Much leverage on the axle with that long arm .. and It pushed the axle Out.
I can see where the fulcrum point is at the edge of the dropout.. its like a crowbar leverage ratio..

I suggest Improving the trailer Hitch + Longer Axle.. get rid of the arm (and the Instep hitch).. put the Hitch right up By the axle.

Burly also uses a Square tube draw bar , Now .
https://www.bikeshophub.com/trailers...le-p-4154.html
replaces their forged aluminum one with Steel

https://www.bikeshophub.com/trailers...it-p-1257.html
The Elastomer replaces the spring, you mention , for a flexible connection

Perhaps You should convert your Rear wheel Hub to a solid axle and then you can get those axle Nuts tight enough
With a Big Wrench, to not come Loose again, since you seem unable to get the QR tight enough. (esp to resist that high leverage)


as evidenced by having your wheel Pull out, .. which started this topic off .

fietsbob

Here is another way to Cope with your rear dropout Type..

https://www.bikeshophub.com/trailers...er-p-2660.html

PatrickGSR94

Oh cool, I like that idea!! Thanks, I've never seen that before but will probably pick up one soon!

fietsbob

Then you can likely screw on the 'In-Step' hitch Under the Provided Nut, the QR lever will be on the Right side, Of Course..

Perhaps use a hex headed Security QR or an internal cam Shimano Skewer..

sarahbruce

I used one of these in the past to pull a trailer and it worked wonderfully! Solid part and bikeshophub is a great place to order parts/trailers.
Bruce

Also, if you want to take your trailer to the next "level", get this hitch- https://www.bikeshophub.com/trailers...ch-p-1537.html and corresponding lollipop- https://www.bikeshophub.com/trailers...op-p-1539.html

These are easily retrofitted to your trailer by removing the spring hitch and bolting the lollipop in its place. This takes all the weird springy back and forth away when carrying a "heavy" load. I prefer this solid lollipop setup hands down to the spring hitch.

ocsawdust

Burley flatbed, never. It does get clamped on the rear triangle tho. 14 years of pulling my dog around.My bob ibex on the other hand has pushed the wheel out of the dropouts twice. I have to admit it was very much overloaded and pretty much still in its shakedown period. Happy with both.

Bholio

I broke a quick release skewer on my Schwinn continental towing a heavily loaded converted kid trailer. I'm pretty sure it was the original skewer from 1973.

My thought was 'duh, of course I cannot tow with a QR axle, the skewer is too thin'. I replaced the axle with a bolt on. I'm surprised there aren't more reports of broken ones.

My trailer was mounted to the QR directly, not frame mounted.

Robert C

I had an old style Burley hitch that would consistently loosen the axle bolt on my bike. I fell off once; but the safety strap caught it and I was able to walk back and find the bolt.

They changed the hitch design slightly and I purchased the new style hitch. I haven't had a problem since.