Dropout Conversion - What do I need to know?

[cryoverkiltmilk]

Scored some glorious roadkill today (pictures later; it's miserable out). 26x4 fat single-speed MTB. Disc brake ready with only a couple parts missing (rear brake looks perfect, front lever, cable, and hardware other than the disc are MIA). Everything on it still looks to be in the correct shape, and tires are filthy but have plenty of tread. Frame has some brands I've never heard of on it along with an assortment of stickers, BUT this may be the (budget-cost) base I've been looking for to turn into a (mostly) weather-proof winter bike.

HOWEVER

Can't be weather-resistant to my satisfaction while it's still got a chain instead of a belt drive (an elegant drivetrain, for a more civilized age), and ideally I'm going to want an internal gear hub in that beastly rear wheel.

What is the actual difference between horizontal rear dropouts and "track end" dropouts, if any? It seems to be a steel frame, so welding shouldn't be a problem. I have a local welder I've worked with for my drift trike before (I have no interest in doing any welding myself, despite how easy some people say it is; it's just not for me), but I want to bring him as much of the homework already done as possible. Should I be looking for a junker frame, and transplant the entire section (end of the 'triangle' that extends away from the rear dropouts), or is it better to fill and flatten the existing vertical dropout structure, then cut and grind out the proper opening? Planning on using Surly Tuggnuts when all is said and done.

What is the difference between MIG, TIG, and brazing?

Can the original disc brake mounts be preserved, or should I be looking for tabs from a site like Frame Builder Supply?

Advice, accounts of similar projects, and/or general measurements are all welcome. Thanks in advance! I'll add photos to this thread tomorrow, if the sun decides to return.

 

[Captain Awesome]

Simple and easy to fill and slot the axle mount over changing the entire thing. IMO

Fill it, weld it completely, drill the forward portion of the new slot, cut the rest out

No reason you shouldn't be able to preserve the existing brake mounts

 

[us56456712]

See here on rat rod bikes under the title “38 - 41 entry level track bike“ to see how I fill welded and put in track slides out. Lots of photos of me doing it. Here is the alignment tool I made. This gets the drops parallel after you fill, slot and lap a new drop on top of the filled and slotted one. It’s got to be perfect or you get annoying chain binding and maybe even skip. You grab the ends of the threaded rods or old axles and bend the drops into alignment.

 

[MattiThundrrr]

Got your back, Clyde. Here's the link:
https://ratrodbikes.com/forum/threads/1938-41-entry-level-track-bike.108736/

 

[GuitarlCarl]

Before you do anything to the frame, you need your new hub and pulley cog in hand. Otherwise you have no reference for width or hole/slot size for the axle. Except for what someone's website may or may not tell you. Parts in hand are always better. You may need to do very little, or you may find it easier to put in a whole new rear quarter (stays and all) from a donor. It's really hard to say without the the pics you mentioned... You got this just don't jump the gun...

Carl.

 

[Karate Chicken Industries]

Can't be weather-resistant to my satisfaction while it's still got a chain instead of a belt drive (an elegant drivetrain, for a more civilized age), and ideally I'm going to want an internal gear hub in that beastly rear wheel.

While I get tailoring a bike to fit personal needs, heavier riders (especially those who push hard) and belt drives do not mix in my experience. Lighter riders or those who don't push hard, I understand not wanting to maintain a chain in Winter.

 

[us56456712]

Got your back, Clyde. Here's the link:
https://ratrodbikes.com/forum/threads/1938-41-entry-level-track-bike.108736/

Thanks

 

[us56456712]

While I get tailoring a bike to fit personal needs, heavier riders (especially those who push hard) and belt drives do not mix in my experience. Lighter riders or those who don't push hard, I understand not wanting to maintain a chain in Winter.

I have noticed that there are no more internal geared hubs or belt drives in our mountain biking club. It was quite a fad about 6 years ago but neither held up. The LBS also noticed that they rapidly failed. I’ve used a chain for winter riding in Michigan’s UP where they use so much road salt that the evergreen trees are ever brown on the roadside. I’ve had many winter bikes over the last 50 years and always used chains. I’ve even left some of the bikes outside without covers all year round. When you go to ride them in November the chain is rusted pretty much into steel flat stock. I just douse it in penetrating oil and ride it skipping and shifting like poo. After a few days riding and a few soakings it’s fine. You can do this for 3 - 4 winters, perhaps longer, but by then the brake blocks or rotors and spoke nipples are rusted and quit working. Then it’s time to remove your studded tires and throw away the bike. Get another unit for the salt to destroy. It’s not worth doing maintenance, just ride and put up with the rust as long as you can. I had one bike in the 1980s that got so rusty from salt getting inside the seat tube that the frame snapped at the down tube/bottom bracket. If I remember I plug the seat post on a new winter bike. I don’t like aluminum seat posts because the salt can corrode weld it in place. I also don’t like fenders because they pack with salt, water, ice and sand that freezes overnight making the bike unridable until it gets warm enough to thaw. I sometimes use a fender that clips on my seat post or a plastic strip on a rear carrier. Nothing on the front. I don’t even bother to try and protect the drive line, can’t be done here plus the guards pack with mush slush and freeze. If you are going to be riding in a salt, snow, ice and sand mush then the belt will slip from the packed ice and the sand will grind down the belt. Here we are in April, May and the first week of June In the last photo. By June I’m riding my gravel bike as the roads are dry. No studs by the middle of April as the ice is mostly gone. You have to be cautious and pick you routs In April and May. The first bike is a $98 Kent Walmart bike. The cheaper the better as this will be scrap in a few more years. I replaced the V breaks with cantilevers because they collect less mush to freeze. I replaced the steel square taper with an alloy one I had and replaced the 700 x 38 original tires with cheap Schwinn 29 x 1.75 knobbiest. They just fit, but more expensive 1.75 tires are too big. This is my spring bike.

Here is my current winter bike with studded tires for hard pack or ice. I also have a winter fat bike for softer stuff.

 

[cryoverkiltmilk]

While I get tailoring a bike to fit personal needs, heavier riders (especially those who push hard) and belt drives do not mix in my experience. Lighter riders or those who don't push hard, I understand not wanting to maintain a chain in Winter.

Duly noted, KC. I'm not looking to do deep-snow riding with this or anything else with hard pushing. Just something for around-the-neighborhood dog-biking/bikejoring, plus the occasional corner store or CVS run.

Also, I'd be lying if I said that having a fat-bike shaped hole in my current garage roster wasn't a factor, along with 'it looks cool'.

For the heavier riders reference, I'm 245 on a good day (down from 272 at the start of the year!) right now, which I know is morbidly obese by e-bike standards, but I'm not sure how it stands for casual acoustic riding, or light MTB riding.

 

[Karate Chicken Industries]

Corner Store runs on a bike, a great habit.

You are a Clydesdale Class rider (as am I) and even for casual riding require the awareness that goes along with it. I've been accused of vanity because my bikes are usually very clean, but regular inspection has prevented me from having at least a dozen catastrophic failures. I'm currently retiring this frame because I found cracks in two of the tubes.

 

[cryoverkiltmilk]

Corner Store runs on a bike, a great habit.

You are a Clydesdale Class rider (as am I) and even for casual riding require the awareness that goes along with it. I've been accused of vanity because my bikes are usually very clean, but regular inspection has prevented me from having at least a dozen catastrophic failures. I'm currently retiring this frame because I found cracks in two of the tubes.

View attachment 178253

My daily rider is a Diamondback Edgewood that I've piled various upgrades* onto over the past couple years, and it's never shown any signs of stress under load.

*Better tires and brakes, Alfine 8, TSDZ2 mid-drive.

 

[Tallbikeman]

Corner Store runs on a bike, a great habit.

You are a Clydesdale Class rider (as am I) and even for casual riding require the awareness that goes along with it. I've been accused of vanity because my bikes are usually very clean, but regular inspection has prevented me from having at least a dozen catastrophic failures. I'm currently retiring this frame because I found cracks in two of the tubes.

View attachment 178253

Another Clyde at 265lbs. I inspect my bikes regularly. Wheels are built with durability in mind. I run a Nishiki Sebring from the 80's that very much looks like yours. Picture below. No frame cracks yet but I'll keep checking.

 

[MattiThundrrr]

Not quite Clyde anymore, just shy of 200. I ride cheap bikes hard on the trails, so I usually do a quick wash after a rough go. Gets the mud off, fresh oil on the chain, and I get a hands on inspection so I know it's ready for the next one. Especially important with older aluminum, as the material has a limited stress life.

 

[us56456712]

I’m 155 pounds and broke the frame on my full suspension fat bike after one year of riding. That’s the problem with aluminum. I have a 300 pound heavy weight lifting buddy that rides mountain bikes a lot. He has so much weight that 25 hard miles with a lot of climbing in the Marji Gesic is what he usually does before he has to drop out. His bikes have not been problems, mostly his size limits him on the bike. In the gym, that’s something else. He has always been big but I think the power lifting is not good for a cyclist as you have to keep yourself big to do it.

 

[cryoverkiltmilk]

I’m 155 pounds and broke the frame on my full suspension fat bike after one year of riding. That’s the problem with aluminum. I have a 300 pound heavy weight lifting buddy that rides mountain bikes a lot. He has so much weight that 25 hard miles with a lot of climbing in the Marji Gesic is what he usually does before he has to drop out. His bikes have not been problems, mostly his size limits him on the bike. In the gym, that’s something else. He has always been big but I think the power lifting is not good for a cyclist as you have to keep yourself big to do it.

Give him a heads up about DirtySixer's IndieGoGo campaign going right now. More affordable than Clydesdale Bikes (made to order titanium) and a domestic option vs Tractor Bike (Australia). Both of those are more of the cruiser/commuter/gravel territory as well.

 

[cryoverkiltmilk]

Photos of the salvage as promised.



Not the prettiest thing I've ever picked up on the side of the road, but it fills the fat-bike-shaped hole in my collection.



Faaaaaaaaat. [He said, as a compliment.]
Front disc brake is incomplete but the remnants seem okay?

Pegs are banged up and rusty but seem true at least. Will break out the almighty socket wrench tonight and make sure they come off clean.



No idea how much of this is actual branding and how much is the previous owner.



What's still here of the brake system seems to be in perfect shape.



I'm going to need a bit more cushioning, and I really prefer a tool-free option for adjusting seat height.



No kickstand. Something interesting about these cranks but I can't say what.



Suspension is nothing special but seems to be in perfect shape.



Hold on... three speeds?



And... more than three speeds. Was this a poor man's single-speed conversion? Trying go to from a hardtail MTB to a wheelie bike?

 

[cryoverkiltmilk]

https://www.aliexpress.com/item/32814758830.html
I think this is what the bike started as. Clearly didn't have those grips, pegs, or Tektro.

 

[Tallbikeman]

I have noticed that there are no more internal geared hubs or belt drives in our mountain biking club. It was quite a fad about 6 years ago but neither held up. The LBS also noticed that they rapidly failed. I’ve used a chain for winter riding in Michigan’s UP where they use so much road salt that the evergreen trees are ever brown on the roadside. I’ve had many winter bikes over the last 50 years and always used chains. I’ve even left some of the bikes outside without covers all year round. When you go to ride them in November the chain is rusted pretty much into steel flat stock. I just douse it in penetrating oil and ride it skipping and shifting like poo. After a few days riding and a few soakings it’s fine. You can do this for 3 - 4 winters, perhaps longer, but by then the brake blocks or rotors and spoke nipples are rusted and quit working. Then it’s time to remove your studded tires and throw away the bike. Get another unit for the salt to destroy. It’s not worth doing maintenance, just ride and put up with the rust as long as you can. I had one bike in the 1980s that got so rusty from salt getting inside the seat tube that the frame snapped at the down tube/bottom bracket. If I remember I plug the seat post on a new winter bike. I don’t like aluminum seat posts because the salt can corrode weld it in place. I also don’t like fenders because they pack with salt, water, ice and sand that freezes overnight making the bike unridable until it gets warm enough to thaw. I sometimes use a fender that clips on my seat post or a plastic strip on a rear carrier. Nothing on the front. I don’t even bother to try and protect the drive line, can’t be done here plus the guards pack with mush slush and freeze. If you are going to be riding in a salt, snow, ice and sand mush then the belt will slip from the packed ice and the sand will grind down the belt. Here we are in April, May and the first week of June In the last photo. By June I’m riding my gravel bike as the roads are dry. No studs by the middle of April as the ice is mostly gone. You have to be cautious and pick you routs In April and May. The first bike is a $98 Kent Walmart bike. The cheaper the better as this will be scrap in a few more years. I replaced the V breaks with cantilevers because they collect less mush to freeze. I replaced the steel square taper with an alloy one I had and replaced the 700 x 38 original tires with cheap Schwinn 29 x 1.75 knobbiest. They just fit, but more expensive 1.75 tires are too big. This is my spring bike.View attachment 178202View attachment 178203

View attachment 178204
Here is my current winter bike with studded tires for hard pack or ice. I also have a winter fat bike for softer stuff.View attachment 178210

Went through an IGH phase from about 2000 to 2013 or so. During that time I tried a variety of Shimano 7 and 11 speed hubs and a 5 speed modern Sturmey Archer hub. I never tried the Roloff which I may cure all the ills that the other two brands exhibit. First the rotary shifter mechanisms for Shimano products wear out fast. Once worn out no one fixes them and the hub becomes useless. Couldn't get the Sturmey Archer hub to stay in first gear under load. Evenutally I put a cassette rear hub in, mounted a derailleur setup and haven't looked back. Dead reliable, no problems. Roloff was too rich for me and I'm happy with the derailleur bikes.