A while back I posed a query up about my Cotic Roadrat that has horizontal dropouts and disk brakes and the way the calliper is mounted it tries to force the disk side of the hub back along the drop out and as a result have to really tighten up the QR squarer. The motion is due to the resultant force of the seat stay mounted brake calliper pushing the disk side of the hub rearwards along the drop out slot (later road rats have callipers mounted on the seat stay). I needed a chain tug that worked in the opposite direction and I’ve struggled to find one.

I was browsing bike packing vids on YouTube and came across this in shown in the screen grab. It shows what appears to be a bracket attached to something similar to horizontal drop out, but has the adjustable screw on the opposite side to as a traditional chain tug.

I’m wondering what this bracket/part is and if I could use it on my road rat? It would potentially have the additional benefit of converting to a thru-axel if there was enough clearance. I appreciate it would probably position the wheel more rearwards and below the line of the sliding dropout, but that shouldn’t be a problem…would give me more tyre clearance against the seat tube.

The bike is a URSA Chumba

Thanks.

I have a vague memory of looking at something like this a while back. I think it was called a Jabbernut or something similar. HTH

Surly Hurdy Gurdy is kind of like a backwards chaintug. https://surlybikes.com/parts/small_parts/hurdy_gurdy

That is a Paragon Machine Works sliding dropout.

Here are the dropouts

http://www.paragonmachineworks.com/frame-building-parts/adjustable-dropouts/sliding-dropouts.html

and these are the inserts

http://www.paragonmachineworks.com/frame-building-parts/inserts/sliding.html

They are good and there are lots of different inserts but they are damned expensive.  It works as a system so you would probably have to swap the whole dropout on the roadrat.

Depending on the thickness of the dropout on the roadrat you could drill through from the front and fit a bolt like in the picture above.

https://shop.bikesandbuddies.co.uk/kona-pj-sliding-dropout-geared-142×12-cc.html