phatswag

Hi Everybody,
I intend to convert commuter/old mountain bike to a Nexus8 IGH wheel and would like to avoid a tensioner. The frame is a c1995 Marin Pine Mountain, the tubing is Tange MTB.
Is it possible to swap these dropouts for something with some horizontal adjustment like a campy 1010 or campy 1053? I'm emotionally attached to this bike so cost isn't really a consideration.

I'm a new member and Bike Forum won't let me post an image of the dropout/chainstay until I've made at least 10 posts, but the chainstays are pretty beefy, maybe 18mm outside diameter and do not taper from the BB shell to the dropout. Please let me know if an image would help in this discussion and I'll find some way to post one.

I've corresponded w/ a local Boston Framebuilder who does really nice work, but he declined saying that he only works on tapered chainstays.
Any advice would be very much appreciated.

Regards and thanks,
Charlie Taylor
Boston, MA

JohnDThompson 

Is it possible? Certainly.

But would it be cost-effective? Probably not, unless you do the work yourself. And even then, it would be considerably more effort than simply installing a chain tensioner with the current vertical dropouts.

Alternatively, you could play around to find a "magic gear" that will work without a tensioner.

Nessism

You can upload photos to flickr or similar and provide a link.

Gresp15C

I asked a similar question sometime back, and the responses are worth a look:

https://www.bikeforums.net/framebuil...eel-frame.html

wsteve464

Here's a link to Paragon Machine's sliding drop outs they have all you need to do this. You or someone will need to braze/weld in the new dropout. If it were me I'd buy just the sliding dropout to see if it is possible to cut out the old dropout and have enough stay length to fit the new one in.

https://www.paragonmachineworks.com/...-dropouts.html

unterhausen

I think I would print out the drawing and see if I could get the dropout to fit using that

Henry James sells a conversion track dropout. https://www.henryjames.com/henry-jame...-dropouts.html

mikeread

Could you just get some 8mm steel plate and make your own.

This way you can make the tabs fit into your existing tubes exactly with as much insertion as you like.

Also maybe you can cut the slots undersize and finish off in the frame to ensure your wheel is straight.

Just a suggestion, I am no expert, maybe the experts can comment if this might be a viable option?

unterhausen

I think making them is a perfectly reasonable idea. You can find the occasional person that does that, usually with 4130 steel. 8mm is a bit thick. The number 3/16"/5mm is floating around in my memory as a reasonable number. Not sure it would be much cheaper than the options listed in this thread so far though unless the OP lucks into a scrap piece.

There was a relatively recent thread about replacing the dropouts on a more recent Pine Mountain for a totally different reason.

Doug Fattic 

There are some big advantages for making your own dropouts to fit internally geared hubs. The tabs can exactly match the width of the chainstays and seatstays. In addition the angle of the tabs can exactly match the angle between the stays on your frame. And continuing the advantages, the angle of the wheel slot to horizontal can be adjusted to match the non-turn washer you will be using that keeps the hub from rotating in the frame. The purpose of choosing this angle (which is separate from all the other angles) is so the gear cable can exit the hub right along the chainstay so it looks right and is easy to hold in place with appropriate braze-ons. Also if those advantages are not enough, it is nice to have a long slot (longer than an old 1010) so adjusting chain tension with whatever chainring and cog is being used is easy to do.

If you want to be super sexy, you can also cut 1mm thick stainless steel plate to be brazed onto the dropout where the wheel axles would otherwise by marring the paint. I can follow up with instructions if you are interested. It isn't that hard to draw and cut yourself. Of course you would have to have a frame builder braze them in. We do a charity bicycle project in Ukraine using internally geared hubs. Having our own dropouts made to fit was a big advantage.

Live Wire 

Thats crazy. I hope that he just didn't want to do it and that wasn't his real reason.

Doug Fattic 

I don't know who he is or an speak for him but I can understand why someone would not want to be bothered trying to do something to match the big stay openings of his MTB frame. Those kind of jobs where he has to figure out what dropouts to order somewhere and then modify so the joints don't look stupid can become a huge time sink - especially if he is not familiar with making a frame for internally geared hubs. And then the extra time spent can create a bill much larger than the customer expected and he is unhappy. For example not every frame builder would know what angle the dropout slot needs to be to the chain stay so the non-turn washer puts the hub in the right rotation. And I'm guessing that if he does find some kind of dropout that works, its tabs will be a lot smaller than the stay openings and that difference can be really ugly when they are brazed together. And then when someone else looks at the job they will say "man that's ugly" and Charlie will say well that is builder X's work. Good frame builders know when to turn down a job when it is not what they typically do so they can't do it efficiently.