PatrickGSR94

I just bought a steel frame with intentions of transferring the parts of my utility bike over to it, since it's larger (utility bike is too small for me). Problem is the rear dropout area is much smaller around the QR mount area. This bike is primarily used to haul my cargo trailer, and I'd rather not have to get a different trailer. Is there any way to make this hitch work on this bike? I'm guessing a spacer wouldn't work.

CliffordK

I have no QR mounted hitches. I built a rear straight-pull hitch for my cargo bike. Two kids trailers connect to the chain stay, and 1 to both the chainstay and seat stay. The Bike Friday trailer has a special air hose connector permanently mounted to the bike.

However, in your case, If you have access to rudimentary welding and machining, there are two solutions I can think of.

1) Replicate a similar mount to yours with a small, but thick upper "washer" cut to the size of the dropout for a tight fit, and then attached to a piece of pipe for the hitch. If you wanted to use your QR as a "through bolt" type release, you could even permanently weld the new hitch to the frame.

2) Weld a short piece of matching pipe to the rear support triangle. Even perhaps welding your existing hitch, or a new replacement one. This would require a frame mod, but it would keep the hitch away from your QR.

ocsawdust

Not sure what kind of loads your moving, but my experiences with my bob has been a learning curve. Bob trailers are hooked to the skewer like your pic showing your hitch bracket. Pulling trailers is not new to me, have had a burly flatbed for almost 20 years. Worked very well for my best friend, till she passed. The bob has been new to me, have wanted one since I first saw them. 6 months ago I picked up a bob. It's not at all what I expected. The flatbed clamped on the left triangle, the bob, the axle. The smartass kid in me had to test it out in all kinds of ways, needed to know if it had limits. It has held up. Some ways I would use it on a last alternative only thing. The one big thing was the weight of the trailer pushing forward and down and putting me in a bad situation, the rear wheel detached. I personally would make a plate just forward of the triangle and do a hard attachment to the frame. The bob being hooked to both sides of the axle kinda spreads the load, the pic of your hitch to the left rear, the complete load force goes through the one point.

PatrickGSR94

Well most of the load is centered over the trailer wheels. Haven't had a problem hauling groceries from the store. It's an InStep kid trailer (100 lb weight limit) made into a flat bed with a box attached to it.

Hate to have to do something custom as it's a really pristine frame. I'll probably just try to sell it. Sucks because it would have taken a rack and fenders perfectly over my 26x1.5 tires.

CliffordK

You didn't give a lot of info about the frame.

So, it is a MTB frame?
The disc brakes might be nice, assuming you're planning to hook them up.

I suppose I wouldn't get too excited about "originality" of a steel utility frame... but that's me, and I was the one that did a Massif Massacre of a Steyr Clubman for my utility bike.

You could make a new hitch mount without damaging the frame if you wished.

It all depends a bit on whether you can weld.

I'm not sure about chrome. Obviously it would be damaged with welding. I'm seeing mixed opinions about welding it, and it would be a pain to try to grind off. Perhaps that would be reason enough to find a solution that would not require welding on the frame.

PatrickGSR94

It's not chrome, it's painted. And unfortunately I can't weld. Tried it once in college architecture school, but never really went anywhere with it. Wish I would have learned more.

The frame is a 2008 (I think) Marin Pine Mountain frame, and it's really nice. Disc only, for 26" wheels, and derailleur cable routing along the down tube. I really, really wanted to use this frame.

However, looking at it more and taking measurements off my other bike, I'm starting to think the frame may actually be too big for me. I feel like my yellow bike is too small, which is about 16.5 to 17" from BB to center of top tube. This frame is 20" BB to TT, and the top tube itself is about 2-3" longer than the yellow bike.

fietsbob

You add a Spacer under the Hitch to get it to clear the frame end , and then maybe get a Tandem length QR skewer

Tandems use 145 hubs instead of 135 so you got an extra CM of skewer length . Shimano makes tandem Hubs.

(Santana Tandems get an even wider Hub)

PatrickGSR94

hmmm interesting. I may think about that. I think I'll have a couple people at the office who can weld, or know people who can weld, look at it to see if they have any ideas.

I'd like to avoid welding if possible, though, just because I'd rather not mess up the finish on the frame.

CliffordK

If you don't want to weld the frame, then I'd build a custom mount to fit your frame.

Or find a better frame.

Does the trailer hitch coupler twist and rotate on the yellow bike? I could imagine making a hitch keyed to the frame so it would stay in a single position, but then any twisting would tend to pop the axle out.... which may not be desired.

It might be a fun project, but I don't think I have those dropouts on any bike, nor the hitch/trailer assembly. I could still try it with some very precise measurements. But, prototyping by mail would be suboptimal.

PatrickGSR94

The hitch has a special washer on the back with a tab that fits in the dropout opening to keep it from twisting.

I looked at the product page for this particular hitch on Amazon and found a number of people with the same complaint about it not fitting these smaller dropouts. One guy posted pics of the bracket he made to make his work, which I may try also. The benefit of this is that it would lower the hitch a little, which would level out my trailer more. Since it has 16" wheels the trailer always slopes towards the back when attached to my 26" wheel bike.

I may try making something similar, but with a larger bracket that comes up and somehow uses the bottom bolt hole of the disc brake tabs to keep the bracket from twisting.

Scroll up for pics: Amazon.com: mkm's review of Coupler Attachment - InStep & Schwinn Bike...

MichaelW

Burley make adaptors for their hitch that fits inside the cowl of a Ritchey or Breezer style cowled dropout.

PatrickGSR94

So this is what I came up with last night. Not sure if I like it. I made it by cutting and shaping a piece of 1" x 1/4" steel, originally from a huge 8" x 8" angle bracket. I was trying to get the hitch lower to level out the trailer, but at this length I'm concerned with the weight of the trailer pulling on the steel bar and rotating the bar backwards, which could wreck the frame somewhat.

The other reason for it being so long is that I used two holes that were already in the bracket. I'm not sure if the drill bits I have could handle drilling through 1/4" steel if I wanted to make a new hole farther up.

fietsbob

Independent problem solving , after some delay, .. nicely done..




Transcontinental Tourists have arrived here , their bikes got boxed Up and shipped .

One rack solution was Mounting the rack on a long bolt that also held the disc Brake adapter On.