Hi, new to the forums, looking forward to participating here as I learn more.

I got a new bike, it's been years since I had one. I searched but didn't find an answer to this specific question..

I have a bontrager rack on a 15" Trek 7100. I also have a trailer hitch mounted so I had to mount the rack post by the wheel in the rear mount. I'm curious if that is structurally sound, or if that's bad news. It seemed like the front hle would be more appropriate, but not possible with the trailer hitch mount.

Being the bike is a 15" it didn't have seat stays, so I mounted a mono stay adapter. Not to the seatpost though, is the location and setup in the image below okay? I didn't want it on the seatpost since I want to be able to ajdust the seat when I put the bike on the hitch rack on our vab (using an adapter bar so it sits level on the hitch rack).

So, some pics to show what I did. I think I'm okay, but wanted to check what others think. Thanks, Tim

mounting racks on a small bike is a pain. i usually use the seat collar that has braze on tabs to get the mounting points higher.

You should be OK since the vertical struts going down to the dropouts take most of the weight of the rack; there is much less stress on the front part of the rack. Several manufacturers make seat post clamps with ears for mounting racks if you would like to explore that alternative. I have taken that approach on one of my bikes and it works well and looks clean. A search on "seatpost clamp rack mount eyelet" or the like will yield numerous useful hits. This is the one I use: https://bontrager.com/model/08427

It doesn't matter which holes at the dropout you use. I wouldn't use a mono stay adapter on anyting other than a mono stay, instead I'd replace the seatpost clamp with one that has rack mounting holes integrated (I prefer this method even with a mono stay). If the QR feature is important, Bontrager makes a clamp with a QR https://bontrager.com/model/08427 all other clamps i've seen use a bolt.

Thanks for the replies. I saw the adapter you both referenced at the Bontrager site, but LBS didn't have them. I am starting to search online for ship to USA. Amazon doesn't have them. Maybe my LBS can order one, but am still checking online for options if they can't.

Thanks!

Generally, the rack is best mounted on the most forward mounting holes in the dropout. This leaves the most aft mounting hole in the dropouts for fender mounting. In this way, the fender stays will be shorter and won't cross over the rack mountings. The seatcollar/clamp mount for the rack also promotes shorter struts to secure the rack. In all things mounted a bicycle, "shorter" means stiffer, less prone to swaying, and more likely to stay tightly fastened.

Good to know, thanks!

I'd prefer using the upper hole since there is more "meat" supporting it underneath.
I'd also prefer to see at least 1 full thread of the screw protruding through.
Just MHO.

"but LBS didn't have them." Neither did mine but they were happy to order them. They may not have been the cheapest price, but there was no shipping charge and I like to keep my purchases local if I can. Too many of my LBS's have closed down and I figure every little bit of buisiness I can give them helps.

But the rear set of holes gives more clearance between the heel and pannier in addition to lowering the CoG. On my touring bike one fender stay is mounted to the front set of holes and the other stay and rack are mounted to the rear set of holes. When mounting fenders or racks I look at all the options and then make a choice.

I cannot see how the the rack, even if it were moved forward an inch, could interfere with the trailer on that bike. I guess it must look different with the trailer mounted.

It's actually the hitch mount on the bike. It's hard to tell from the picture, but the rack mount extends just low enough to overlap the hitch mount. It's so close that in the picture it looks like it could be moved forward, but it can't, it doesn't overlap much, but they do interfere with each other.