Non-vintage tandem into "stretch cruiser"

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(If anybody gets a sense of "deja vu" reading this thread, it's probably because I first talked about this bike and my plans for it back in December, when I first got it: http://ratrodbikes.com/forum/index....intage-tandem-into-stretch.88747/#post-874993 There's going to be some duplication as I attempt to consolidate everything down into this "build thread," so apologies in advance! It's also going to be a LONG thread, much like the bike! ;) There's also apt to be a little editing along the way as I've never tried an epic thread before, so...you've been warned.)

I'd been lurking around this forum for a year or so before joining, and hanging around for a year marveling at the amazing stuff that RRB members create. My bike "building" skills are nowhere near the level of many of you guys -- I've tried my hand at welding exactly once, I've never used an angle grinder, I've never laced a wheel, and I haven't taken a hub or bottom bracket apart in about 40 years. If I had to put a label on my skills, I'd say I'm a "journeyman bicycle mechanic" -- I learned how to fix and repair my Huffy Cheater slick as a kid, to tune and adjust my three road bikes as a teenager, and to tune up and replace parts as needed on my first two mountain bikes as an adult. I also (eventually) learned the valuable lesson of "I tried to do it myself, not only failed but made it WORSE, and now it's going to cost three times as much to pay a shop to fix it than if I'd just paid them at the beginning." Whoops. :banghead:

To put it another way, I worked on bikes and kept learning, right up to the point where I hit a plateau and started breaking stuff when I tried to climb higher -- so I stopped TRYING to climb higher at that point. Now I've got more experience, and the internet, and this forum, and I'm starting over again -- but at least I don't have to start over from the very beginning! :)

The point that I'm flailing around to make is that this build (like my other "bolt-together builds") don't require much special knowledge and don't require ANY special tools. Anybody who's willing to learn a little basic bicycle maintenance (which is probably everyone here at RRB) and who's willing to do a little research could and can put together a bike like this.

...and all of you guys with specialty tools and a lot more mechanical skill could easily build a much better, MUCH COOLER version in half the time! :113: So...on with the craziness!

Part I: Concept, Acquisition, and Original Plans

I'd been ogling and lusting after some of the amazing stretch cruiser builds around here, but I've been trying to finance my new bicycle hobby like I do some of my other ones: "I don't mind spending a little bit here and there, but I don't want to get sucked into spending hundreds of dollars all at once."

I didn't want to spend a hundred or two on a frame...then another hundred on wheels...and another hundred or three on miscellaneous parts. I've also written at length about the fact that I'm getting old (51 later this month) and live in a somewhat "rolling" area with hills, and at this point have ZERO desire for a single speed bike again. (I used to deliver about 75 big-city newspapers every day, weather permitting, on a 1940's or 1950's balloon tire Schwinn, up and down hills, and couldn't WAIT to get home and park it and get on my Schwinn Varsity and LeTour IV.)

"A tandem looks to be about the same size as a stretch cruiser, and some of them have seven or more speeds!" I realized. "Now I just have to find one -- preferably a cruiser-style frame -- on craigslist or something for cheap!" Eventually, after months of searching, I found one and a week's worth of hilarity (in hindsight) ensued while trying to contact the owner to purchase it. Thankfully, we finally connected and met up and I looked it over. Also in hindsight, I think I learned to never again buy a bike in a well-lit (but still dark) McDonald's parking lot in the cold December rain, but for the most part the bike looked to be in great shape and I was happy to pay $75 for it -- which even included delivery to my house a mile away!

As I said in that other thread, "The only things wrong with this bike when I got it were miniscule: it needed one new inner tube, the front derailleur needs adjustment since it won't drop into the low chainring, the stoker seat wobbles horribly because the "nose bolt" underneath fell off somewhere, the front chain was derailed and both chains need lubed. There are a few paint nicks in the "bottom tube" that connect the bottom brackets, but they're not even through the primer. I feel like I got a great deal on it, even though it's a department store bike, probably built in the same Chinese factory where they build the Micargi and Walmart Schwinn tandems. The hubs were well greased, the bottom brackets felt smooth on my one short ride around the block, and the rims were almost perfectly straight when I got the bike. (The derailleurs and other components are pretty low-end, but I can always upgrade them with [I think] standard mountain bike parts.)"





As I also said in that other thread, "This may be the shiniest bike in "Fresh Finds" in 2014, huh?" ;)





My original plan, which I mostly adhered to, was to remove the front seat and stoker handlebar, move the rear seat forward with a custom solid post from slowriderz, remove the rear cranks somehow, replace the front handlebar with apehanger bars, build "stick shifters" out of the stock Grip Shifts and move them back to the middle of the frame.

Also, to make things both easier AND more difficult, I decided that I didn't want to make any permanent changes to the original bike itself -- I wanted to be able to change it back into a tandem if I ever wanted or needed to.

 
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Part 2: Custom Seatpost, Learning As I Go, the Wrong Handlebars, I Hate Winter

The first thing I wanted to do after I got the bike into the garage was to figure out exactly HOW I was going to sit on the back seat and ride it. I had a couple of ideas, though, so the first time the weather got significantly above freezing here in Ohio in December, I was riding up and down the driveway, sitting on a series of half-baked banana-like "seats." I made them out of folded-up towels, cardboard, plastic wrap and duct tape and "attached" them to the twin top tubes just in front of the rear seatpost.

I sort of liked the IDEA of a custom banana or recumbent style seat, but it was too low for my legs to get anything close to a proper leg extension. Since I plan on actually RIDING this thing -- not just around the block -- I quickly established that a normal saddle would be just about perfect, if my legs were about 4" longer.

I had ordered three other absolutely AWESOME seatposts from Chad (aka slowriderz) at Chop Shop Customs for some other bikes: http://ratrodbikes.com/forum/index....layback-seatposts-re-stocking-for-2015.59700/

For anybody who hasn't heard of these posts (and is too lazy to click that link) these posts are beyond amazing! They're meticulously crafted from SOLID BAR STOCK, custom built to the customer's specifications, and can be designed to whatever angle(s) or sizes they can dream up. "Solid bar stock" means that they're made of SOLID STEEL, not tubing, which means that they're not going to bend while someone is riding their bike, as cheaper lighter posts might. The only downside to these posts is that they can be measured in POUNDS or KILOGRAMS -- as in "plural" and not "in fractions of." (The guys at my local bike shop were suitably amazed when they saw my second post, and weighed the post and attached saddle on their "bike scale" as "about six pounds.") These posts would probably make hard-core roadie "weight weenies" cry all over their carbon fiber frames and titanium bolts (and is that such a bad thing?) but they're NOT going to bend, even under some very heavy riders. :)

So -- I pestered Chad with multiple stupid questions that he's probably heard a hundred times, but as always he was very friendly, helpful, and prompt with his replies! Yes, he could EASILY make a post bent beyond 90 degrees, if I could just tell him the exact angle I wanted. Yes, he could also make a post with MULTIPLE bends, if I wanted! (The post I ordered is shaped like a number " 7 " but I was toying with the idea of one shaped like a number " 7 " with two more bends in the top piece.)

Eventually I figured out how to measure the exact angle to get the top of the "number 7" to be perfectly horizontal -- I used MS Paint and a picture of a protractor that I found online, and decided that the "72 degree" angle that showed me was probably about right for a cruiser frame. Remember this stuff from Mrs. What's-her-name's 8th grade geometry class?



Of course, I could have told Chad that I wanted a post with an INTERNAL angle of 72 degrees and he could have done the math himself, but why make his life more complicated? ;)

Despite my insistence that this order was NOT a rush, partly because I wasn't about to actually GO RIDING around in Ohio in December, and mostly because it WAS December and the holidays were around the corner and he probably had better stuff to do, Chad still got my seatpost built, painted, and delivered to me inside of two weeks! :grin: (Thank you again, Chad -- but that was totally unnecessary and above and beyond my expectations! :113: )

With post in hand, though, I couldn't wait to put it on the bike, put a saddle on it and see how it felt (and looked!) I grabbed a set of REALLY tall apehangers I had attached to the correct sized stem and tried it out:



The seat and post were perfect! The handlebars...well.... I decided that they were too tall for this bike, too, but that a more normal pair of lower, wider apehangers would be just about right.

As you can see from the picture, before the seatpost arrived I had been braving the cold and working on other facets of the bike. I wasn't sure what to do with that empty seattube where the tandem "captain" would normally sit. IF I didn't want to keep all of these custom changes reversible, it would be easy to cut that tube down so it was flush with the top tube -- but I didn't want to do that.

I ALSO wasn't looking forward to having to re-cable the derailleurs and adjust them, since I didn't think the stock cables would reach up to taller handlebars. Before I even signed up at RRB, I'd seen a thread where BigCam69 had gotten creative and taken a Grip Shift and turned it into an old-school-looking stick shift: http://ratrodbikes.com/forum/index....hifter-mount-and-stickshift-conversion.66386/

Last summer I did the same thing, and posted about it because I hadn't realized I was using the EXACT SAME shifter he had used, since the shifter in his picture was apparently missing the top cover. Whoops. http://ratrodbikes.com/forum/index.php?threads/stick-shift-from-grip-shift.84900/

"Well, why not use the captain's seatpost and that little "stoker stem" that normally holds the stoker's handlebar, and mount TWIN stick shifts on that?"

I turned the stem around so it was facing forward, flipped it upside down so it wasn't pointing up at the sky, and cut a piece of 7/8" dowel rod to the proper length. Since that stem is built like a BMX stem with a separate front "plate" it clamps down even smaller than its normal 1" diameter, so I didn't have to shim the dowel to keep it from twisting. I slipped the Grip Shifts on the dowel, tightened everything up, and took it for a short spin.



I liked the POSITION of the shifters well enough, but I definitely wanted the "stick shift" pieces on there. As mentioned above, the handlebars were too tall, or about chin height. Beyond that, though, the riding position was low and stretched out, and from my waist down the bike really felt a LOT like a Micargi stretch cruiser I rode briefly last fall. I was pretty happy with it, and only had one more big hurdle to clear.
 
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Part 3: Online Shopping, Cutting, Grinding, More Grinding, Even More Grinding, I Give Up.

Everything about a tandem drivechain was new to me. Before I bought this bike, I had no idea of the different ways different companies connect the front pedals to the rear pedals and ultimately to the rear wheel. This style of bike uses a "timing chain" on the left side of the bike to connect the front and rear pedals and keep them in "synch," and then those rear pedals drive a normal chainring and a normal chain on the right side of the bike, connected to the wheel.

When I'd looked at the bike the first few times (in the dark, in the cold, and/or in the rain) I realized that I'd probably have to remove the rear pedals, or better yet, the cranks. Those first few glances made me incorrectly think that they were "three piece cranks" kind of like some old BMX cranks, where the chainring wasn't actually attached to the crank!

In that other "Fresh Finds" thread RustySprockets already knew (without pictures!) more about my new cranks than I did, and thanks to his explanation I was a lot better prepared when I finally got around to pulling the rear chainrings off.



That may LOOK like the crank is separate from the chainring -- there's a gap between the two pieces of metal, right?



Uh, no. That crank is indeed "fused" to the chainring, and it's not the simple operation that I had hoped to just unbolt the crank and slap a few washers on the spindle. "Whooops" once more. ;)

In that other thread, we talked about some of my options. There was "remove the rear chainrings, swap the front chainring to the right side, and have a six-speed bike with a REALLY long chain." There was "remove the rear chainrings, move them to the front (or buy another triple chainring for the front) and have an eighteen-speed bike with a REALLY long chain." There was "either of the above, with the addition of an 'idler pulley' to take up the slack on the new long chain," and there was "cut the cranks off the chainrings" but since I didn't want to do anything irreparable....

I wound up shopping around on eBay, where I've often joked that people can find ANYTHING if they're willing to look long enough. I went looking for "triple chainrings" and found a LOT of "chainring plus crank" sets. Since I was going to try to just cut the cranks off two chainrings, I didn't want to spend a lot of money. Eventually I found someone selling FOUR "triple chainring with crank -- RIGHT SIDE ONLY." I have no idea where those four left side cranks went, nor does it matter since I didn't want or need them, but I bought two triple chainrings for about $10 each and another $10 in shipping.

The silver plastic "spiders" with the Sakae stickers simply popped off the front of the chainrings.



I tried to cut the cranks off with a Craftsman single-speed rotary tool -- sort of a generic "starter Dremel" -- and quickly realized that the small cutting wheels were going to be too small to reach through the crankarms, and the small cutoff wheels are very fragile and egg-shell-like. I wound up at my local Sears Hardware, where I bought a "kit" with two large cutting wheels, more small wheels than I need, and several "sanding drums" that I'd need for the next step. Someone with more skill than I could probably have taken those cranks off with an angle grinder in a few minutes, but I don't have that sort of skill...or an angle grinder, either. ;)



After I got the cranks cut off, it was time to start grinding those sharp edges into something approaching a circle. In a perfect world, I'd have been able to get the remains of the cranks to form a perfect circle, mirroring the "stock" half-circle on the other side so they looked perfect. In the real world, after spending well over an hour at it and using up four sanding drums, I was left with some nicely rounded-off square edges.

"I could spend another two hours and use up the other four drums and still not be much closer. Or worse, I might take too much material off. That's close enough -- if I put some flat black spray paint on there, nobody will know the difference," I thought, and I'm sure I'm not the first person to think that some flat black primer will hide imperfections!





I still need to paint those, and I'm considering putting those plastic "spiders" back on, but I'm not sure how they'll look. Since they just snap on and off, though, I guess I'll find out!
 
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Putting It All Together, Test Riding, Building Shifters

I really didn't have too much trouble putting it together -- as mentioned before, the ChopShopCustomz seatpost is awesome and a perfect fit for the frame! Unfortunately for me, as I told Chad via e-mail, mounting a saddle backwards like this presents its own set of challenges: all of these "sprung" seats seem to be constructed slightly differently, and of the four or so saddles I have like this, two of them had a big part of the metal "frame" right behind the clamp, where the post needed to go.

Luckily, this Schwinn saddle has an arch in the frame rail, so it fit quite nicely -- but if I ever need a new saddle in the future I'll have to pay attention to the way it's constructed.



<need to insert another picture of the BACK of the saddle where it meets the seatpost>


The shifters were really easy to build this time around, since I had plenty of practice last summer. I learned that the flat style of PVC caps weren't long enough to fully cover the shifter -- this project really requires the curved or "domed" type of cap instead. A few holes, a little grinding of two bolt heads, some washers and bolts and wooden knobs and they're ready for some paint! Since I used a wooden dowel rod for my "handlebar" it was easy to drill holes through the middle of the cap for a bolt to screw into the dowel to keep the new shifters securely in place.



I had a little trouble sourcing spherical wooden knobs, though. Two hardware stores I checked didn't carry them, and a woodworking specialty store only sold them by the dozen. It turns out that craft stores sell them individually in all sorts of sizes -- from 1" to 2 1/2" diameter -- as "wooden doll heads!" These 1 1/2" (?) knobs were only about $1.50 each, and the 2 1/4" knob I bought for my other bike was $2.00 or so. They're mostly spherical, with a small flat part on one side, with a small hole pre-drilled most of the way through it. I enlarged the first half-iinch or so of each hole with a drill and they screwed right onto my 1/4" threaded bolts, cutting their own threads as they went.


The modified chainrings went on quite nicely, and as far as I can tell, fit perfectly. To my eye, the largest of the left-side chainrings lines up perfectly with the front chainring. I had a tiny problem since I was going from (as I recall) a 44-tooth stock ring to the current 48-tooth -- that small difference made the left-side chain about two links too short. That was easily fixed with a chain tool and "whoops!" once again as I had managed to forget about the different widths of chain. I had several discarded 3/32" chains that I could use for spare links, but the formerly-single-speed left side chain uses a 1/8" chain. A quick trip to my local bike shop solved that problem for free, and I spliced in the new section.

I don't think that I'll cause any premature wear to the rear chainring by using too wide a chain, and that side doesn't need to "shift" between chainrings anyhow. Those other two chainrings are just along for the ride and provide the right bottom bracket spacing. ;)




Here's the almost-finished project -- all it really needs in my opinion is a little bit of spray paint on the shifters and the new chainrings, and the removal of about half of the nineteen decals on the frame.



It really rides pretty nicely -- the long frame absorbs a LOT of the bumps along the road! The stock 2 x 2.125 cruiser tires absorbed a little more of the bumps, but the Kenda 838's I had in my garage have a lot less rolling resistance, and I really like them because of that.

I have to remind myself that it's not my "other cruiser" and that this one rides a lot more like I imagine a recumbent bicycle would. Standing up on the pedals isn't really an option, MOSTLY because of the position of the handlebars! I thought I was clever when I mounted the stick shifts so I COULD in theory stand over them if I have to: "low" on the front derailleur has the shift lever completely horizontal, pointing ahead, and "low" on the rear derailleur has the lever horizontal, pointing backwards. There's plenty of "standover height" available, but the handlebar is practically leaning on my hip bones.

Still, on my first "big ride" of the spring, it climbed the 1/3 mile long, 6% grade hill near my LBS about the same as my seven speed cruiser. I'll ride the first tenth of a mile, pass the first side street and think "this isn't so bad!" and keep on going. After the second tenth of a mile I'll pull into the second side street, catch my breath for a minute and realize that I'm not a teenager any more. :p Then I'll head back up the hill, pass the third side street and think "pfffft -- I'm almost to the top now!"

It IS a bit of a weird sensation to be sitting that far behind the pedals and still be sitting that far in front of the back wheel! Because it's so long, turning is a little bit of a challenge, but that's mostly a matter of planning ahead and realizing that it doesn't handle like a normal bike. I can make a "U" turn on a two-lane residential street without putting my foot down or hitting the curbs on either side, but so far I take up THE WHOLE ROAD when I do it. Maybe I'll get a little better with some more practice.
 
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Part 5: Paint, Clean-up, Removing Decals, Future Craziness

I'm waiting for warmer weather for painting and picture-taking. After a few mediocre coats of paint, I decided that "silver" wasn't the best combination for the PVC shifter caps AND the knobs. Since the caps are $1 and the knobs are $1.50, I decided to start over on those -- but I'm thinking "black" now so the PVC caps blend into the black shifters themselves.

 
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Thanks! We're supposed to get more snow tonight, but if spring ever gets here I'm hoping to finish the "touch up" painting and then take this thing out on the road for some "on-location" photos. (Garage doors aren't terribly scenic.)

Over the weekend I found myself thinking about repainting the frame, shortening and re-routing some of the cables if I do that, and/or building a fake "tank." Like my last "project bike" I'm also wondering "how do you know when these things are finally 'finished?'" ;)

4/12/15 -- spring appears to finally have sprung, so I took it out for a ride and a few more pictures:






A close-up of the seatpost, without the taillight in the way.


The chainrings aren't quite perfect, but unless people look closely I don't think they look that bad.







There are a few minor things to be worked out yet -- I'm not wild about the factory (?) kickstand mounted to the rear triangle. There's a kickstand mounting plate directly in front of the rear tire, but I'm not sure I'll be able to fit a normal kickstand in there and not hit the rear leftside chainring. (There's a phrase you don't often hear -- lots of bikes have three chainrings, but how many bikes have chainrings in three different locations?!)

I'm also trying to figure out something to do with the visible hole in the front seatpost. I'd like to plug that with something, and BuzzRocker 13 has suggested putting some sort of cupholder there.

I still need to peel off some of those decals, and I'm half-tempted to paint the frame or spray it with a few coats of Plasti-Dip.

The biggest minor problem I'm having is that idler pulley -- it makes quite a racket as I pedal, and I strongly suspect that's because the pulley is the same size as found on most 6, 7, and 8 speed derailleurs. The "teeth" are designed for that narrower 3/16" chain, but the timing chain (and front crankset) are designed for single-speed 1/8" chain. The chain seems to want to twist slightly as it goes over the pulley, which means that the edges of the chain rub against the pulley supports. I'm hoping it's just a matter of "dialing in" the pulley tension, and I replaced the pulley wheel with a slightly wider version, but it still makes a lot more noise than I'd like.

It seems to ride okay without the idler assembly, but the chain droops quite a bit -- but I don't think I can shorten it any more than I have already, even with a BMX-style "half link."

I'm toying with ideas for building a new idler assembly, but I don't feel like paying for one -- some of those tandem-specific assemblies cost more than I paid for the bike itself!
 
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Okay -- I think this build is 99% finished! :113:

Someday when I'm thinking about it, I need to pull the shifters off the dowel rod, pull the dowel rod out of the stem, and paint it black. On the other hand, there's only about 3/16" of bare wood showing on either side of the shifter, and unless you're standing directly over the shifters (or riding the bike with the sun directly overhead) it's really hard to notice that little flaw.

I didn't think to take pictures of the solution I came up with for the noisy idler pulley. Basically, the problem was the way it was designed and/or assembled. The bracket that suspends the pulley was possibly designed for a wider pulley, but when the bolt/axle was tightened the sides of the pulley went from being a rectangle in cross section to a trapezoid. Since it narrowed toward the axle, whenever the chain would shift or twist slightly, the sides of the chain would rub against the inside of the bracket, making an awful clatter. Once I recognized exactly what was causing the problem, it was easy to put a couple of washers on either side of the pulley, making the bracket "square" again and giving the chain more room to travel without hitting the sides!



As I mentioned earlier, I took most of the sticker/decals off the frame:



...and was EXTREMELY impressed at the silver-to-red fade that the Chinese frame painter had done...and then someone at the factory apparently decided it would be "better" to cover that fade with ugly decals. :banghead:



But the decals came off fairly easily, and left what I think is a pretty good-looking paint job!



I figured out how to cap the hole in the "captain's" seatpost -- with a chrome road bike bar-end plug! It fit pretty nicely though I had to force it into the slightly smaller diameter post, so taking it out might be a little bit of a challenge.

Here's a close-up of the shifter assembly and plug:


You can also see the inexpensive bicycle computer I installed on the frame and rear wheel.

A side view of the shifter (now painted black) and the computer:



Another side view of the seat (and once again I forgot a picture of the rear and those "support beams"):



Side views of the finished project:





I'll try to come back to this thread once more when I can add some pictures of the seat, and of myself sitting on and/or actually riding this! :) Like a lot of my other hobbies, I wouldn't even have THOUGHT of doing something like this if it weren't for this forum, but luckily you guys ALSO gave me the know-how to put it together!
 
Okay, not "riding pictures" per se, but you can see how I fit on the frame:





The seatpost "height" is about perfect for me at full leg extension, but it might be a bit far for people with shorter legs. The only thing I would change about the riding position is that I wish the standard apehanger bars were just SLIGHTLY longer -- two or three inches more than the "normal" 13 inches tall would be ideal, I think, but the 25" extra-tall apehangers would probably be too much.

I probably should have thought to have a picture with both feet down, but from the position of my right foot, you can tell that it's quite easy to put both feet flat on the ground!
 
Thanks, guys! I've wondered about turning the stem around backwards as well, but couldn't find many cases of other people actually doing it.

Since it's a short BMX stem, and since it's only going to move the bars back about two inches, I don't think that it would make the bike handle THAT much differently -- and with you two guys thinking it's a good idea, I think I'm going to try it! :)
 
Thanks, guys! I've wondered about turning the stem around backwards as well, but couldn't find many cases of other people actually doing it.

Since it's a short BMX stem, and since it's only going to move the bars back about two inches, I don't think that it would make the bike handle THAT much differently -- and with you two guys thinking it's a good idea, I think I'm going to try it! :)
Nothing wrong with reversing threaded stems or even regular threadless stems. I did it all the time on bmx bikes as a kid & used the bolts to attach brackets to hold stuff; baseball bat across the bars, tire iron for a car, & even a small/medium wooden box to carry stuff. Before I knew about racks & baskets were old women items. If you had an angle grinder (buy 1 they're handy & Cheap at Harbor Freight) & a cheap little 110 welder you could make your own stems. 1 of the things on my to do custom bicycles lists. I want a taller stem but I also want to do some kind of trick bends in it
 

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