Trailer hitch to bicycle seat?
 

I picked up an old jogging stroller and I'd like to convert it to a Travoy style trailer. I'd prefer to attach the hitch to the seat rails to avoid clamping to any of my carbon fiber seat posts. I'd like to make my own hitch. Any good ideas or thoughts out there? Are the seat rails on a typical bike seat strong enough? Here's a picture I found from a bicycle company that has an attachment for the Burley hitch to give as an example of what I'm thinking about doing:
https://stridacanada.ca/wp-content/u...5/P1140171.jpg

https://lh3.googleusercontent.com/qm...=w1250-h937-no
https://lh3.googleusercontent.com/Qo...E=w703-h937-no

I dunno man but I'm skeptical. I pulled kids on one of those giraffe one wheel bike attachment things that attached to an adapter on my seat post. I wouldn't want my seat rails to be pulled and pushed by a trailer, and they are higher up still than my seat post which used to make my bike rather wobbly with a kid sometimes....

Seat rails aren't that strong, I'd n be concerned of damaging them.

Hmmm...

That Strida appears to be a custom mount specifically to the Strida bikes. I am thinking it is actually bolting onto the seatpost clamp, something similar to the vintage post clamps.

https://cdn11.bigcommerce.com/s-804s...=2&imbypass=on
I'm going to disagree with @djb. One's seats can take quite a bit of abuse. And, thus the rails too, if done right.

I'd make sure that one clamped onto both rails (or the seatpost top as above).

How heavy of loads?
30 pounds-ish?
50 or so?
100+?

Cliff, well I certainly admit, who knows. I figure the most important thing is that the attachment system is very solid without any play. That's what I recall about the kid rear wheel only thing we had, that play would put a lot of forces int to the attachment point, and I could always feel it working the joining part.
if there are working systems for seat rails it should be easy to find them. I've only ever seen trailer attachments on the low down chain stays.
And I clearly recall the strong forces pushing pulling and moving my bike around with that kid bike thing we had. It wasn't pleasant with it , especially when the kid would lean to one side and or the play in the system moved.
This is why I'm skeptical.
Good luck finding a potential system that you can improvise with this jogging trailer.
i assume your bike is carbon? ie no chsinstay option.

what could go wrong?

https://cimg5.ibsrv.net/gimg/bikefor...362558fb08.jpg
https://cimg6.ibsrv.net/gimg/bikefor...5de1bce0f4.jpg
https://cimg7.ibsrv.net/gimg/bikefor...18d8c0d252.jpg

wow
as devils advocate, those are pretty darn rusty seat rails!

If I'm not mistaken it's okay to bolt a trailer to a carbon bike chainstay, it's the clamping to carbon that is the issue. I could be wrong but in my research on carbon bikes and if I could use one with racks or trailers.

If you can get/make a bracket attach it to the quick release, they make ones for that purpose. When I switched to a disc brake I had to go from a frame clamp and just bought and made the parts to make it work. Seems the safest all around.

I snapped the rail of a high quality saddle that was fairly new. Don't know when during the ride it happened (noticed it when I was finished), but I did hit a really big bump at some point.

how about one of these seatpost-clamp-rack-attachment-thingies?
no idea how much weight it could handle, or how it would react to bumpity roads.

https://lh3.googleusercontent.com/5d...1000-l75-e7-rw

https://www.treefortbikes.com/Proble...CABEgKvdfD_BwE

I use the seatpost attached "Ventura" Zinc coated bicycle hitch. It looks a bit like a small version of the kind of ball you'd see on a truck trailer hitch. I use it to tow my golf clubs (which aren't light) a few miles to our local golf course, up & down hills and partially over bumpy roads. It's always worked well for me:

https://cimg2.ibsrv.net/gimg/bikefor...c96e41890a.jpg
https://cimg7.ibsrv.net/gimg/bikefor...658d815012.jpg

And any high up attachment will require a rather long pole, as shown in golf bag setup, and how the trail a bike things are.

Thanks guys! I don't want to break a seat rail.

I stopped by the bicycle co op yesterday and found a narrow-ish standard two piece seat clamp for a dollar. It's slightly wide to fit behind my seat clamp on the rails. I'd need to grind it down a little to get it to fit. I'd rather clamp to the seatpost, but I don't want to damage any seat posts.(I also have a bike with a dropper post)

https://cimg7.ibsrv.net/gimg/bikefor...f7be259174.jpg
Steel seat rail clamp

Agreed. I am wondering how to bend the pole properly to get the optimal angle on the trailer. The stroller had quite a bit of aluminum tubing I can repurpose. I want to be careful before I start cutting the tubing. I was thinking something like a tie rod end might have too much flexibility and allow the pole to pivot down too far. It looks like the Travoy might use some type of a rubber bushing. I've seen people use a section of hydraulic tubing as a hinge. I'd expect the tubing would need to be replaced as it ages.

could you, like, hit the coop again, buy a cheap seatpost you can use for touring?

You mentioned cf seat posts, but what are the chain stays?

Sure could 🙂. I really don't need the trailer. I like to tinker when I have free time. I have a vintage CF Specialized Epic that would be fun to use for easy short tours and shopping trips. It has an aluminum seat post.

(My vintage Klein MTB has a CF seatpost, but I just bought a new bike with a dropper post I intend to use with bicycle packing bags.)

The reason I keep bringing up chain stays is because there are lots of existing chain stay attaching systems already. I pulled kids in kid trailers using these and they work very well, keep push pulling motion down low.

bob skewer works if you can fabricate a mounting yoke.

would also protect the chainstays.

what kind of chainstays, by the way?

https://www.rei.com/product/716798/b...E&gclsrc=aw.ds

Do you have the option of using an axle-mounted hitch coupler (that goes inside a QR skewer clamp)? I have a trailer that I converted for cargo use from a Thule Chariot that works well.


https://cimg4.ibsrv.net/gimg/bikefor...30f28df2fc.jpg
https://cimg5.ibsrv.net/gimg/bikefor...6f1aa9b6de.jpg

I could look into it. I used to have a trailer like that when my son was young. We also had a tag-a -long which was wonderful to use. I actually went out and bought a vintage Diamondback MTB just for that purpose and built it up as a bomb-proof tourer.

When we had the tag-a-long, it took some explaining to get my son to stop trying to steer the bike by leaning, wiggling, etc. I was lucky to have it attached to that DB. It is one solid bike. Heavy bike though...

They're all vertical- nonreplacable dropouts. Spacing ranging from 130 to 135 except for my new mountain bike which has the Trek Boost system. The Bob skewer would work with my Specialized and the Klein. I wasn't planning on it, but another fun project might be to build it like an Extrawheel.

Nice trailer! You could haul quite a bit with that!

i think you can replace the long rod part of the bob skewer with a generic skewer rod......