# Has anyone built a Twin Bar from a Schwinn cantilever frame?



## cbustapeck

I just purchased this Schwinn Cruiser Seven for the Shimano Nexus 7 speed internal hub wheel set, with the idea of selling off the remainder of the bike to cover the purchase cost. 

I'd love to own an Elgin Twin Bar, but they're more money than I care to spend, and I've heard bad things about the flexibility of the frame. A bicycle that I'm worried about breaking because of how expensive it is, combined with it flexing and making me worry? No, thank you.

The idea of a Schwinn Twin Bar came to mind and I started thinking through it. 






Note: I'm writing this because I know absolutely nothing of structural engineering and because I want input on structural engineering. Take any "I think" or "it should" statements with that massive grain of salt.

I see two big issues with getting rid of the seat post: 
1. A significant amount of weight is being placed on the frame at a point without structural bracing.
2. You've made this major structural compromise and the aesthetic advantage of it is hidden mostly by your legs!

If we remove the seat from that position, both of these problems are solved, at least somewhat. 

The visual of the rack isn't bad. I was thinking about a custom cushion to go on top of it, with the intended sitting position above the rear axle. That way, the majority of the weight is supported by the axle, rather than the frame. 

Has anyone tried something like this? What are your thoughts about structural stability? What major issues, other than those of having another bike in the house, am I missing here?


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## Andrew Gorman

Break out the hacksaw or angle grinder and test it out! There will be more flex and wiggling, but you can see just how much before you commit to the whole project. You can still sell of the other bits if you want to.


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## Frank and Pam Skid Kings

I'm not an engineer, so like you said I won't comment on structure, but...there were a lot of Elgin Twin bars made and a lot still exist. I think the flex on original is somewhat of a myth. They ride great, built like a tank, just don't go jumping with them (or any old bike). That being said if you can live without all Twin extras, the frames are fairly easy to come by and not a lot of money. It's when you start talking "all original" it gets scary (trust me ,I know). Sell off your parts bike and check around for a Elgin twin frame, usually under $400 with wheels, sprocket etc. Less if you get just a frame. Ether way good luck and have fun !


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## cbustapeck

Frank and Pam Skid Kings said:


> I'm not an engineer, so like you said I won't comment on structure, but...there were a lot of Elgin Twin bars made and a lot still exist. I think the flex on original is somewhat of a myth. They ride great, built like a tank, just don't go jumping with them (or any old bike). That being said if you can live without all Twin extras, the frames are fairly easy to come by and not a lot of money. It's when you start talking "all original" it gets scary (trust me ,I know). Sell off your parts bike and check around for a Elgin twin frame, usually under $400 with wheels, sprocket etc. Less if you get just a frame. Ether way good luck and have fun !



Seriously? I must be looking in all the wrong places!


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## Frank and Pam Skid Kings

cbustapeck said:


> Seriously? I must be looking in all the wrong places!



I bought one in January that had been for sale on line for a month for $450. Nice frame, good but incorrect seat, nice wheels and tires, bars, a rider when I picked it up. Missing the head shroud, crank shroud, no chain guard, no rack and oh no fenders or kick stand or original Elgin grips. Still a good looking bike without all that stuff. I did add most of that, gave me something to hunt down during covid and no swap meets. Here's a not bad deal that may or may not still be available, but gives you an idea.  https://thecabe.com/forum/threads/elgin-twin-bar-frame-set-and-wheels.169999/


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## Freqman1

There are a lot of bikes more susceptible to breaking than a Elgin Twin--post war Monark's come to mind. I had a Twin and rode the heck out of it and never noticed flex. I would waste my time trying to weld one these Chinese bikes. If you want a Twin save some coin and get a frame like F&P said. V/r Shawn


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## cbustapeck

I did it! 





The lines work even better than I had hoped. 

Yes, there is some flex, but less than my girl’s 1935 Silver King - not that that is saying much. I feel comfortable using it as a rider, but definitely not with my weight sitting over where the seat post was. 

For what it’s worth, I weigh a good bit more than the average rider that these bikes were designed for - at least in 1935.


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## Superman1984

cbustapeck said:


> I did it!
> 
> View attachment 1307221
> 
> The lines work even better than I had hoped.
> 
> Yes, there is some flex, but less than my girl’s 1935 Silver King - not that that is saying much. I feel comfortable using it as a rider, but definitely not with my weight sitting over where the seat post was.
> 
> For what it’s worth, I weigh a good bit more than the average rider that these bikes were designed for - at least in 1935.



It definitely improves the looks of the cantilever frames. You know you could weld flat bar under the top tubes; either in sections or 1 solid piece to stiffen it. Mind if I ask what you paid for the bike? I have the exact girl's model I bought for an ex for $75 minus a rack (If it came with 1?). I need to replace the push button shifter though. Debating the Nexus 7 swap to my Nirve Switchblade until it's motored.


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## cbustapeck

Superman1984 said:


> It definitely improves the looks of the cantilever frames. You know you could weld flat bar under the top tubes; either in sections or 1 solid piece to stiffen it. Mind if I ask what you paid for the bike? I have the exact girl's model I bought for an ex for $75 minus a rack (If it came with 1?). I need to replace the push button shifter though. Debating the Nexus 7 swap to my Nirve Switchblade until it's motored.



. 
I paid $90, delivered. It’s a solid bike, but not as nice as it looks. It spent a good bit of time outside. 

I think the prospect of a wheel set that you can just swap into any number of bikes and have a range of gears alone is worth a good bit.


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## Superman1984

cbustapeck said:


> .
> I paid $90, delivered. It’s a solid bike, but not as nice as it looks. It spent a good bit of time outside.
> 
> I think the prospect of a wheel set that you can just swap into any number of bikes and have a range of gears alone is worth a good bit.



Not bad at all. Mine has some dings & scuffs but not complaining vs what I seen the Nexus 7 going for online alone & useable parts. Guy said he was selling his gf's bike since she didn't ride it & had he known it was like $350+ he said he wished he listed it higher. I was thinking of using an aluminum La Jolla bicycle frame tube to convert it into a boys top bar bike; notch the top tube to the seat post & around the goose neck bolted on since can't weld aluminum. Jus' haven't ground the aluminum welds down & actually decided it's worth the hassle. Currently debating using the fenders & parts for a '53 Monark Rocket or an early post war CWC Roadmaster which I want to convert into a straight bar since it's original but has break at the seat tube & crank. It'll be all steel & welded proper.


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## cbustapeck

I definitely like where this is going. 

I am working on figuring out the seating arrangement. Resting on the rear axle makes the most sense, both for structure and the shape of my body, but I am not sure how I am getting there yet.


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## Bill in Bama

It does look smooth! Now im thinking about it??


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## cbustapeck

Bill in Bama said:


> It does look smooth! Now im thinking about it??View attachment 1310112
> View attachment 1310115
> 
> View attachment 1310116
> 
> View attachment 1310126



Do it! 

One big thought: 
I would _strongly strongly_ consider keeping the seat clamp in place until you are 100% sure of how the seat is to be held in place. I am thinking about a banana seat, which would still need a clamp, even if the vast majority of the weight would be over the rear axle. 

More likely, though, I am going to trade it off to the guy at my bike shop, less the wheels, in trade for wheelbuilding for my Luxury Liner. (It's not that I don't like it, it's that I initially bought it for the wheels, and I would rather have the Luxury Liner on the road than this bike.) 

It's also worth noting that it got the fun accessories that it did because I already had them on hand and had not been able to use them. The build was partially an excuse to use said accessories.

All that said: 
DO IT!


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## Bike from the Dead

cbustapeck said:


> Do it!
> 
> One big thought:
> I would _strongly strongly_ consider keeping the seat clamp in place until you are 100% sure of how the seat is to be held in place. I am thinking about a banana seat, which would still need a clamp, even if the vast majority of the weight would be over the rear axle.
> 
> More likely, though, I am going to trade it off to the guy at my bike shop, less the wheels, in trade for wheelbuilding for my Luxury Liner. (It's not that I don't like it, it's that I initially bought it for the wheels, and I would rather have the Luxury Liner on the road than this bike.)
> 
> It's also worth noting that it got the fun accessories that it did because I already had them on hand and had not been able to use them. The build was partially an excuse to use said accessories.
> 
> All that said:
> DO IT!



You aren't planning on trading this bike project _before _you finish it, are you? I really want to see what this would look and ride like in a finished state.


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## cbustapeck

Bike from the Dead said:


> You aren't planning on trading this bike project _before _you finish it, are you? I really want to see what this would look and ride like in a finished state.



I am. 

The lines of this bike are as close to perfect as I can make them, except for maybe some minor details. 

I’ve thought long and hard about seating options, and everything that I have come up with detracts from the aesthetics or costs far more than I care to spend, and might even not look right once done. 

I may have brought this bicycle as far as I can. It may be time for someone else to use their creativity to bring it to completion.

It is also a matter of financial choices: I’d rather have the wheels built for my Luxury Liner and finish that project than keep this one around while I think about it.


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## Bike from the Dead

cbustapeck said:


> I am.
> 
> The lines of this bike are as close to perfect as I can make them, except for maybe some minor details.
> 
> I’ve thought long and hard about seating options, and everything that I have come up with detracts from the aesthetics or costs far more than I care to spend, and might even not look right once done.
> 
> I may have brought this bicycle as far as I can. It may be time for someone else to use their creativity to bring it to completion.
> 
> It is also a matter of financial choices: I’d rather have the wheels built for my Luxury Liner and finish that project than keep this one around while I think about it.



I understand. Still, it would be an interesting experiment to play around with. I might be testing it out on this trike I'm building right now, but I might see about getting a cheap Huffy or something to do some more thorough experimentation on this idea.


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## Superman1984

Bike from the Dead said:


> I understand. Still, it would be an interesting experiment to play around with. I might be testing it out on this trike I'm building right now, but I might see about getting a cheap Huffy or something to do some more thorough experimentation on this idea.



What do you want to know? Save yourself some hassles. I can tell you pretty much from experience on cantilever style frames. There's reasons I don't care for them both aesthetically & build wise


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## Bike from the Dead

Superman1984 said:


> What do you want to know? Save yourself some hassles. I can tell you pretty much from experience on cantilever style frames. There's reasons I don't care for them both aesthetically & build wise



Well, I'm mostly hoping to figure this out for my _Poison Apple_ muscle trike build. I don't know if you saw the latest update to it, but I'm thinking of removing the seat tube and original top tube, and converting the frame into a boy's cantilever style frame, sans seat tube, but with the headset angled back and the tank portion all welded to the frame. Like this bike, I plan to put the seat over the rear axle, except mine's a trike, and the rear axle is behind the bike frame. I want to know if my idea would still be strong and rigid enough to work, especially with a 250lb guy riding it.


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## rustjunkie

cbustapeck said:


> I’ve thought long and hard about seating options, and everything that I have come up with detracts from the aesthetics or costs far more than I care to spend, and might even not look right once done.





i’m seeing a bobber seat in the space between frame and fender, with a mount up front and springs attached to mounts welded to the seat stays


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## Superman1984

Bike from the Dead said:


> Well, I'm mostly hoping to figure this out for my _Poison Apple_ muscle trike build. I don't know if you saw the latest update to it, but I'm thinking of removing the seat tube and original top tube, and converting the frame into a boy's cantilever style frame, sans seat tube, but with the headset angled back and the tank portion all welded to the frame. Like this bike, I plan to put the seat over the rear axle, except mine's a trike, and the rear axle is behind the bike frame. I want to know if my idea would still be strong and rigid enough to work, especially with a 250lb guy riding it.



I don't know about 250 lbs on most standard bikes but as long as all the weight isn't on where the seat tube is removed it should be fine. On twin tube stuff like cantilevers the seat tube helps distribute the weight to keep it from collapsing/cracking the frames. They're engineered almost like a car's leaf spring but not meant to flex via seat tube. I say too much weight over the rear tire or tires in your case of a trike conversion & it will wheelie or pop up. I would still try to go in front of the axle and after the original seat post as my main weight point


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## Superman1984

rustjunkie said:


> i’m seeing a bobber seat in the space between frame and fender, with a mount up front and springs attached to mounts welded to the seat stays
> 
> View attachment 1311977



Using a Schwinn OCC seat I have something in mind that I am fabbing up. It's the same principle basically


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## Bike from the Dead

Superman1984 said:


> I don't know about 250 lbs on most standard bikes but as long as all the weight isn't on where the seat tube is removed it should be fine. On twin tube stuff like cantilevers the seat tube helps distribute the weight to keep it from collapsing/cracking the frames. They're engineered almost like a car's leaf spring but not meant to flex via seat tube. I say too much weight over the rear tire or tires in your case of a trike conversion & it will wheelie or pop up. I would still try to go in front of the axle and after the original seat post as my main weight point



I actually sat over the axle during one of my figuring stages and it didn't feel like the trike wanted to wheelie. If it does wheelie though, I may just put some wheelie bars on the back, because hey, who wouldn't want a trike that can do wheelies on command?

I'll definitely take your advice though and test the seating position out when I can find someone who can help me put this trike together. Thanks for the input.


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## Superman1984

Bike from the Dead said:


> I actually sat over the axle during one of my figuring stages and it didn't feel like the trike wanted to wheelie. If it does wheelie though, I may just put some wheelie bars on the back, because hey, who wouldn't want a trike that can do wheelies on command?
> 
> I'll definitely take your advice though and test the seating position out when I can find someone who can help me put this trike together. Thanks for the input.



Not a problem man. It may not wheelie but I can't say I know of any 250 lb dudes sitting right at the axles on a bicycle or trike. Wheelie bars are jus' cool anyways and if necessity a must. A lot of motorized bikes need them once they're making any kinda real power


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## Bike from the Dead

Superman1984 said:


> Not a problem man. It may not wheelie but I can't say I know of any 250 lb dudes sitting right at the axles on a bicycle or trike. Wheelie bars are jus' cool anyways and if necessity a must. A lot of motorized bikes need them once they're making any kinda real power



Well, this one's going to pedal-powered. It'll _look _and _sound_ motorized, but I'll be the one powering this trike when it's done.


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## cbustapeck

Bike from the Dead said:


> I actually sat over the axle during one of my figuring stages and it didn't feel like the trike wanted to wheelie. If it does wheelie though, I may just put some wheelie bars on the back, because hey, who wouldn't want a trike that can do wheelies on command?
> 
> I'll definitely take your advice though and test the seating position out when I can find someone who can help me put this trike together. Thanks for the input.



Wheelie bars and wheelies? How can you possibly go wrong?


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## cbustapeck

rustjunkie said:


> i’m seeing a bobber seat in the space between frame and fender, with a mount up front and springs attached to mounts welded to the seat stays
> 
> View attachment 1311977




I do like that idea, and the shape of the seat may be just the direction I go, but I want the seat position further back. (I want to be able to show off the lack of seat post and better distribute the weight.)


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## cbustapeck

Bike from the Dead said:


> Well, I'm mostly hoping to figure this out for my _Poison Apple_ muscle trike build. I don't know if you saw the latest update to it, but I'm thinking of removing the seat tube and original top tube, and converting the frame into a boy's cantilever style frame, sans seat tube, but with the headset angled back and the tank portion all welded to the frame. Like this bike, I plan to put the seat over the rear axle, except mine's a trike, and the rear axle is behind the bike frame. I want to know if my idea would still be strong and rigid enough to work, especially with a 250lb guy riding it.




You’re only about 10 pounds over where I am, so I hope my data may be useful. 

I am actually liking placement behind the rear axle - I am just trying to figure out how to support it. Here’s, visually, the best idea I have so far. I apologize for the mess.


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## bikewhorder

I don't think you're gonna enjoy riding the bike like that. The riding position will be extremely awkward. Maybe with some really long handle bars and some kind of back rest. But then obviously keeping the front end on the ground is going to be a challenge, you might need like a wheelie bar.


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## cbustapeck

bikewhorder said:


> I don't think you're gonna enjoy riding the bike like that. The riding position will be extremely awkward. Maybe with some really long handle bars and some kind of back rest. But then obviously keeping the front end on the ground is going to be a challenge, you might need like a wheelie bar.



Your point about balance is well taken, and moving to a point over the rear axle or forward is probably a good idea. 

As for comfort: I’m 6’8”. Just about everything is a bit awkward, and I am used to it. Some things a bit more awkward than others, yes, but so it goes. 

Thank you for that suggestion.


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## Superman1984

cbustapeck said:


> Your point about balance is well taken, and moving to a point over the rear axle or forward is probably a good idea.
> 
> As for comfort: I’m 6’8”. Just about everything is a bit awkward, and I am used to it. Some things a bit more awkward than others, yes, but so it goes.
> 
> Thank you for that suggestion.



Can I call you Brother Lurch from now on? Lol. Damn man I imagine if it's not a stretched out limo bike it is awkward riding most anything. Monkey on a coconut feeling? That's me on like most 20" & 24" bikes or anything with a lifted seat post and I'm 5'8"


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## cbustapeck

Superman1984 said:


> Can I call you Brother Lurch from now on? Lol. Damn man I imagine if it's not a stretched out limo bike it is awkward riding most anything. Monkey on a coconut feeling? That's me on like most 20" & 24" bikes or anything with a lifted seat post and I'm 5'8"




How about the Jolly Green Giant instead?

As for ride quality, well, there's a lot of awkwardness, both in the bicycle world and outside it. 

The only one that I haven't been able to get over is my 1917 Hawthorne. The geometry was just so weird.

Fortunately, minivans are good for my long legs and hauling random bicycles found cheap.

I see these bikes like an older sports car. Expensive, awkward, not the greatest for going to work or in bad weather, but so freaking fun.


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## Superman1984

cbustapeck said:


> How about the Jolly Green Giant instead?
> 
> As for ride quality, well, there's a lot of awkwardness, both in the bicycle world and outside it.
> 
> The only one that I haven't been able to get over is my 1917 Hawthorne. The geometry was just so weird.
> 
> Fortunately, minivans are good for my long legs and hauling random bicycles found cheap.
> 
> I see these bikes like an older sports car. Expensive, awkward, not the greatest for going to work or in bad weather, but so freaking fun.



You got it Jolly Green Giant! I understand the room situation even at 5'8" I have been in stuff like fieros, mgs, vws, and they feel like being in oversized go carts. I have went as far as modifying the seat rails & tracks many a time. Lol. I used to have a Chevy Astro Awd 4.3 and that was 1 of my favorite modern day rides + haulers. Thing fit a few hoods, engines with transmissions & other large parts willingly. Captain's chairs are comfy man seats hahaha


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