Showing posts with label tandem. Show all posts
Showing posts with label tandem. Show all posts

Wednesday, October 25, 2017

Titanium tandem by Waltly

I've already documented my previous tandem projects here before. The primary use of the tandems is for family bike rides with the kids. Two years ago I replaced my old Bike Friday tandem with the Experia tandem and have been happy with the results. Heather has still been using the modified Raleigh I acquired several years ago, but it's very heavy and never has been a very good fit for her. Now that the kids are both tall enough to ride a full sized tandem, it is time to consider replacing the Raleigh. The primary challenge is getting a good fit for a tandem pilot who rides a 50 cm road bike, and with the potential to fit a stoker who is taller (our 13 year old is already taller than her mom). The M/S sized tandem by Cannondale comes close, but is still a little big. So, getting a good fit would probably require a custom frame. In order to keep costs down (the goal was to build the complete tandem for a price close a stock Cannondale tandem), I went with a titanium frame made by Waltly in Xiamen, China.

I've been following Waltly for a few years as I've considered our options when upgrading tandems, along with Titanproduct and XACD. As I understand it, all three of them build OEM frames for various bike companies, and well as offering custom frames direct to consumer. All of them can be found on Alibaba or Aliexpress, along with a few others that I'm less familiar with. Just during the last few months, Waltly has re-done their web site to be by far the most professional looking I've seen, including a nice form to fill out for requesting a quote.

I initially contacted Waltly through a link on their web page and got a response the same day from Amy. Her English is pretty good, and she generally responded to my mails quickly given the 13 hour time difference. I sent her a picture of a frame with similar geometry and specified all of the key dimensions. Waltly's process is to quote a price, and then to ask for 50% of the cost to be paid up front before their engineers start making detailed drawings.

I made two key choices that dictated a number of the other details. One was the the Boost through axle standard. This means 148x12 rear and 110x15 front axles. This is an MTB standard that is relatively new, but I think makes a lot of sense for tandems, especially the wider front wheel (rear hubs wider than 148 have been used on tandems before). I did this because I want durable wheels and because I hope the standard becomes sufficiently common (for MTBs if not for tandems) that there will be many stock wheel options available in the future. The second choice I made was to try as much as possible to replicate the geometry of Heather's road bike on the front end of the tandem, but simultaneously eliminate the toe overlap that her road bike suffers from, because I think toe overlap is much more important to avoid on a tandem. Both of these choices led to the decision to have Waltly make a custom fork to go with the frame because no stock carbon tandem forks currently offer the wider spacing, and because I needed a higher than usual fork offset. My original proposal was parallel 73 degree seat and head tubes, but this was putting the front wheel far too close to the front bottom bracket. Eventually I settled on a 71 degree head tube. While this may make the handling a little more sluggish, it is frequently done on smaller frames, including Cannondale's smallest road tandem. With the slacker head tube it is possible to extend the fork offset to 55 mm while still having a reasonable amount of trail. I asked Waltly to allow for 700C tires between 32 mm and 40 mm width, with the idea that I would have the option of 32mm road tires or 40mm gravel tires. The distance between front and rear bottom brackets was determined by two considerations. First, I want the option of a Gates belt drive in the future, and second I want the spacing as far apart as possible to accommodate taller stokers, so I chose the largest spacing that will support a Gates drive.

After making my initial specifications and paying the deposit, we went through several iterations of drawings before I decided they were ready. Much of this had to do with trying to increase the distance between front bottom bracket and front axle because of the toe overlap problem. Now that I've done this I realize I could probably have used something like Bike CAD to figure that out beforehand and get through the process much faster, but Amy was patient and responsive with my continual tweaks. The final drawings looked like this:



In addition to the frame and fork, I asked for an adjustable stoker stem. About 6 weeks after I approved the drawings, Amy sent me an email with a set of detailed photos of the finished product.






When I gave my approval based on the photos, the frame, fork and stem were shipped by DHL, and arrived in the US just 3 days later. The build quality of the frame looked great. I'm not an expert on titanium welding, but the welds on the finished frame all look very neat. As I got started on the build I discovered that Waltly had made a mistake on the stoker stem, building it for a 28.6 mm diameter seatpost rather than the 31.6 mm diameter I had specified. I sent Amy a photo, she consulted with the engineers and builders, and they agreed that they had made a mistake. They created a new stem as I had specified and sent it to me at no charge. I commend Waltly for their responsiveness in fixing their error.

Before completing the build, I added some yellow and green paint using stencils. I love the look of titanium, but wanted to add a little more color to go with the yellow and green trim I was adding to the bike. I think this is a great solution for customizing a titanium frame that's relatively easy to do and still allows the titanium color to show through. The saddles don't match the rest of the scheme as well because they happened to be preferred saddles from previous bikes.



I built the bike up using a SRAM Rival drivetrain with mechanical disc brakes so that I could add bar-top auxiliary brake levers.


I used Sugino XD cranks front and rear. We wanted a low gearing range, and don't particularly need high end gears because we don't go that fast, so I used what's currently being referred to as "subcompact" gearing: 46/30 chainrings with 11-32 cassette. This is of course not something SRAM designed their 2x11 road groups for, and I found I had some difficulty getting the front derailleur to avoid overshifting and dropping the chain to the outside. The Sugino cranks are designed as a triple, so I installed a chain guard in the position of the outer chainring, and it seems to have solved the problem for now.

The one mistake I made in my design was forgetting to specify a front derailleur mount, which was my original intention. There are many clamp-on front derailleurs available, so it wasn't a big deal, except for the fact that the location of the water bottle mounts on the rear seat tube have limited the range of movement available to me for vertical placement of the front derailleur. So far I have been able to get things working. If I were to do it again, I would want either a derailleur mount with a wide vertical range, or put the bottle cage mount in a different location.


For the captain's pedals, I happened to already have a pair of old Shimano M324 pedals. To go with the yellow color theme, I took them apart and painted the main body with the same yellow paint I used elsewhere, and did the same on the platform pedals I currently have installed on the rear. I also found some gold anodized chainrings for the timing chain. They were originally intended for BMX bikes, so they required a 1/8" timing chain.



The wheels were custom built by ProWheelbuilder.com, using Hope Pro 4 hubs and Velocity Chukker rims. When we discovered that they offered colored spokes, we couldn't resist paying a little extra to get yellow spokes, which turned out to match the existing yellow trim very well. Currently the wheels have Kenda Happy Medium 40mm tires installed.

I included mounts for rear racks in the design. I built the bike with 203mm discs front and rear for maximum braking power. Waltly only had post mounts available for 160 mm rear rotors, so I used a 160-203 mm adapter on the rear brakes. The fork had IS mounts.



Even with the 700x40C tires, there is plenty of clearance. I tried inserting a MTB wheel in the frame with 27.5x2.1 tires and they appear to fit, so that will be an option we consider in the future for riding gravel roads.



Overall I had a great experience working with Waltly and would definitely do it again.






Wednesday, September 21, 2016

3D printed cable guide for X-Peria tandem fork

In my original entry about the X-Peria tandem, I noted that the fork did not have an obvious method for routing the cable to the disc brake, but that there was a screw hole on the inside of the left fork blade. My solution was a 3D-printed bracket designed to attach to the screw hole and reach around behind the fork blade where the cable would pass through it.

I used OpenSCAD, a free CAD software to create the design. This is an OpenSCAD rendering:


Note that the hole for the screw mount has a flared shape to accommodate an angle-head screw, so as to minimize the amount the screw protrudes into the space inside the fork. The OpenSCAD source code for this design is below:

guidelength = 20;
width = 15;
cablesize = 5;
thickness = 1.5;
screwhole = 5;
len1 = 5;
len2 = 5;
th2 = 2.5;
angle = 70;
bendradius = 10;

$fs=0.01;
$fa=3;

r2 = screwhole/2+4;
cr = cablesize/2;
ofs = width/2-r2;
d = (guidelength-width)/2;

rotate(angle) {
difference () {
    union () {
        // cable guide outer
        translate([0, 0, -d]) cylinder(guidelength, r=cr+thickness);

        // connector section 1
        translate([0, -th2/2, 0]) cube([len1, th2, width]);

        // connector bend
        translate([len1, -th2/2-bendradius, 0]) rotate([0, 0, 90])
        rotate_extrude(angle=-angle) {
            translate([bendradius, 0, 0]) square([th2, width]);
        }
    }

    // cable guide hole
    translate([0, 0, -d-0.01]) cylinder(guidelength+0.02, r=cr);
}


// connector section 2
translate([len1, -bendradius-th2/2, 0]) rotate([0, 0, -angle])
translate([len2, bendradius+th2/2, width/2]) rotate([90, 0, 0])
translate([0, 0, -th2/2])
    difference() {
        hull() {
            cylinder(th2, r=r2);
            translate([-len2/2, -ofs, 0]) cylinder(th2, r=r2);
            translate([-len2/2, ofs, 0]) cylinder(th2, r=r2);
            translate([-len2-1, -width/2, 0]) cube([1, width, th2]);
        }
        translate([-len2-r2, -width/2-0.05, -0.05]) cube([r2, width+0.1, th2+0.1]);

        // Screw hole
        translate([0, 0, -0.05]) cylinder(th2+0.1, r=screwhole/2);

        // flared hold for angle head screw
        translate([0, 0, -1]) cylinder(screwhole/2, screwhole, screwhole/2);
    }
} 

The part was printed in white ABS plastic by Shapeways. I have produced other parts using Shapeways before and have found the results to be very high quality. A couple of weeks after placing my order, the cable guide arrived.


The hole for the cable was actually just a little too tight for the cable to fit, so I widened it slightly with a drill. This is actually the second version of the design, the result of some changes I made to my first design after I had a chance to test it on the bike. Here is the final product, installed on the bike.




Sunday, December 20, 2015

X-Peria 5200 Tandem


It's now been over 5 years since I bought the Bike Friday Family Tandem. I have no regrets about it, but I'm ready for something new. I eventually gave up on the conversion to drop handlebars, because even with the various tweaks I made, shifting never worked quite as well as the original shifters did, so I put the original flat handlebars back earlier this year. The telescoping seatpost was important when my kids were shorter, but now the kids are tall enough to fit some full size tandem frames. I also found the Bike Friday to be fairly heavy (around 50 pounds) and I felt that the frame lacked stiffness, a feature that can be partly attributed to its geometry.

My requirements for a new tandem were:
  • Full size frame that's a reasonable weight.
  • $1500 or less. I don't know how long my kids are going to be interested in riding with me on the tandem, so I want to avoid putting too much money into something that might not be used much.
  • Fit a tall rider (me) in front and a shorter rider in the rear.
The Cannondale Road Tandem 2 comes in over $3000, and newer used ones routinely sell on eBay for nearly 70-80% of that. One other option is the KHS Milano, which has a list price of $2000 for an aluminum road tandem with disc brakes and Shimano Tiagra. The only way to get a good road tandem for less than that is to buy used. The problem with most older used tandems (with the notable exception of Cannondales) is that most 1990s and early 2000s tandems had level top tubes that work great for two riders of similar size but would be much to tall in the back for me. Sloping top tubes that can accommodate a larger height differential have become much more common on tandems in the last 10 years, but many of those newer tandems are usually out of my price range. There is a steady stream of used tandems on eBay, but the number of older used road tandems of the appropriate size and price range turns out to be relatively small, and the number of those sellers willing to ship a tandem (a necessity when you live in west Texas) is smaller still.

After searching eBay for some time, I eventually stumbled onto a listing for the X-Peria 5200 tandem frame, which was being offered new for somewhere around $500 by the French online bike shop CR2V. The frame is offered in two sizes, the larger of which is pretty close to the correct measurements for me. At this price I decided I could build my own for something close to my target price. CR2V has a number of eBay listings for frames that they offer to ship internationally, but there are more options available directly on their web site, which is how I eventually ordered my frame. The site is completely in French, so I had to navigate it with the help of Google translate at times. It turns out the $500 price tag included the eccentric bottom bracket but did not include a fork, however they do offer a package with BB, fork and headset for about $90 more. Shipping to the USA is not available as part of the normal checkout process on their site, but after some emails back and forth with them, they offered to ship to the USA for an additional 100 EUR. Total cost was just over 700 USD including shipping. When I placed the order, they had just run out of stock, so there was some delay while a new frame was ordered from the manufacturer, which took nearly 3 weeks. After the frame was finally shipped, it was only a little more than a week until the frame arrived.

At first glance, the frame has a lot in common with a Cannondale, but a closer inspection shows that the welds don't look nearly as clean as can be expected on a Cannondale. I would compare it to the quality of frame one typically sees on lower end aluminum road bikes in a local bike shop. While X-Peria is clearly a French company, it's not clear to me whether the frames are made in France or somewhere in Asia. Regardless, as long as the frame holds up, it suits my purposes just fine. The combined weight of frame, fork, headset and eccentric bottom bracket is about 9 pounds.


The specifications on X-Peria's web site do not specify whether the fork is aluminum or steel, but I believe it is steel because the fork blades look too small to be aluminum, and the junction of the steerer tube (which is clearly aluminum) and fork crown suggests an interface between two different metals rather than a single continuous piece of metal.

The frame has post mounts for 180 mm brake discs front and rear. I used 203 mm brake discs with 180-203 Shimano adapters and Shimano BR-R317 cable-actuated brakes.


The rear dropout spacing is 135 mm, so it's compatible with 29er MTB wheels. Nearly all higher end 29ers now use through axles, so most quick-release 29er disc brake wheels are targeted at less expensive bikes, which gave me a number of good options at a reasonable price, particularly since cost and durability were higher priorities for me than weight. I ended up with these 32-spoke WTB SX19 wheels. 36 and 40 spoke wheels are common on tandems, but it's difficult to find pre-built wheels with more than 32, and I think these will be sufficient for me. The tires shown here are 37 mm Continental Contact, though their actual width appears to be a bit less than 37 mm. Both wheels fit in the frame easily. The fork could easily fit 40 mm tires or bigger, but the rear doesn't have much extra space.


For the drivetrain, I bought used Shimano Ultegra 6603 shifters (3x10 speed) and a 9-speed Shimano Deore XT rear derailleur. (Shimano 10-speed road shifters will work with 9-speed MTB derailleurs but not 10-speed MTB derailleurs). I set it up with single-side drive, which means I'm only using 2 of the front shift positions, but I have the option to use a triple in the future. The reasons for single side drive were keeping cost down (I already had one of the cranks I needed) and size options. I am using a 180 mm front crank and 165 mm rear. When the kids get a bit taller, I will probably eventually go to 170 rear and 175 front with regular tandem cranks.

The rear crank is made by Origin8. It's inexpensive and also comes in even shorter lengths, an ideal option for someone setting up a single-side drive tandem for a short stoker. I used 39 tooth chainrings for the timing chain because I already had one in that size. The inner two rings pictured here are 48 and 32 tooth rings, which have been paired with a 11-32 10 speed cassette. This gives a gearing range just slightly lower than a 50/34 compact road crankset with similar cassette. The 1:1 ratio of the low gear should be enough for moderate climbs and the high end is more than enough for how I anticipate using the bike.

The finished bike comes in at 38 pounds as pictured, a full 12 pounds lighter than the Bike Friday. I don't have an exact cost total, but it came in somewhere between $1600 and $1700. It is probably possible to build one of these in a similar way with true tandem cranks (such as Sugino XD) for under $1800.


The frame has a few quirks that I didn't expect. None of them are serious flaws, but things that might have been helpful to know about in advance:
  • shift cables are routed for a top-pull front derailleur. As far as I know, this means most road derailleurs won't work.
  • only 2 water bottle cage mounts.
  • no guide for brake cables on the fork, as would be expected on a disc brake fork.
  • There are double threaded eyelets on the rear dropouts, but no rack eyelets at the top of the seatstays. There is, however, a threaded hole underneath the seatstay bridge and chainstay bridge, which is presumably for mounting a fender. I'm working on a custom bracket for attching a rack I have that uses this hole.

Saturday, May 17, 2014

New shifters and derailleur on the Bike Friday tandem

Last year I switched the Bike Friday tandem to road-style drop handlebars. The Sachs (now SRAM) Dual Drive system has a 3 speed internally geared hub with 7 speed rear derailleur. The system came with Grip Shift shifters, which work great, but are for flat handlebars only. At the time, I had read a couple of sources that I consider to be reliable claiming that any 7-speed Shimano drop bar shifter is compatible, so I found a set of 1990s vintage Shimano RSX 3x7 shifters on eBay. The triple left shifter worked great on the internally geared hub, but the 7 speed right shift lever never seemed to work quite right despite several efforts to readjust it. It seems that the cable wasn't pulling the derailleur far enough to get all 7 gears, so it would work OK for 2-3 gears but not the rest.

Initially, I assumed that one possible reason for the poor shifting was that the RSX shifter mechanism was simply wearing out due to its age. At some point recently I discovered that in the last year or two, Shimano has started selling a 3x7 drop bar shift lever set for the first time in many years. The 7 speed Tourney group appears to have been available for a few years and is found on various low-priced bikes, but only last year was a drop bar shifter made available. So, my first solution was to try swapping out the RSX shifters for a brand new set of Shimano Tourney 3x7 shifters.



These shifters sell online for about $90. Amazingly, after buying these I sold off the old RSX shifters on eBay for $65, so this swap ultimately only cost me about $25. I'm constantly amazed how much some vintage bike parts will sell for. The Tourney shifters have the thumb lever like Shimano Sora did until about a year ago. I prefer the "behind the brake" location for the upshift lever, but this works fine. These also have the "indicator" that shows you what gear you're in, another feature I associate with lower end Shimano road groups, and which I always assumed I didn't need. As it turns out, it's actually been nice to have the gear indicator on a tandem because it's not as easy as it is on a single road bike to know how many gears you have left just by looking down.

The Tourney shifters didn't solve my shifting problems. At this point, I started measuring how far the shifter pulls the cable compared to the original shifter that came with this bike, when it finally dawned on me that the rear derailleur on this bike was expecting a different cable pull (known as "actuation ratio") than the shifter was pulling. I had assumed that because the spacing of the 7 rear cogs was identical to Shimano 7 speed systems, a 7 speed Shimano shifter would work with this, without giving any thought to the rear derailleur.

The original derailleur is labeled "Sachs Centera". I can't find any documentation on this old shifting system. Sachs was bought by SRAM in 1997, so I'm assuming this bike and Dual Drive system was made around that time, because I don't think it's much older than that.


Regardless of the technical details, I was pretty sure the derailleur was the problem, but didn't want to spend a lot of money on trial and error. All I needed was a derailleur that's compatible with Shimano road shifters. For $15 on Amazon, I got this "SunRace R80", which claims to be Shimano-compatible.


This is designed for an 8 speed system, but Shimano 7, 8, and 9 speed all use the same cable actuation ratio, just with the clicks spaced closer together, so in theory this derailleur should work with any of them as long as the shifter is compatible with the spacing of the cogs. With the new derailleur installed, I can now finaly reach all 7 gears! Shifting is still a little sluggish sometimes. The derailleur hanger is slightly misaligned, so I'm going to try fixing that, but it could also be that this is just how a $15 derailleur shifts. In any case, I'm happy enough with this setup that I'll stop messing with it for now.

Tuesday, October 22, 2013

Short Cranks for Kids on Tandems

In my first post about my Bike Friday tandem from last year, I showed a picture of the Ride2 crank shorteners I first used for making the rear crankarms a more suitable length for riding with small kids on the back. Crank shorteners get the job done, but they are a bit expensive ($110 on Amazon right now), and they have the effect of spacing the pedals out further away from the bottom bracket (the so-called Q factor). I would assume this is more noticeable to riders with short legs, so I think it's a less than ideal solution. Since the Bike Friday was already set up with single side drive due to the DualDrive shifting, the rear cranks can be replaced with any standard crankset.

When we acquired another tandem last year, I put the crank shorteners on that bike and tried using a short crank on this one. The cranks pictured here are made by Sinz, who make parts for high-end BMX bikes. These cranks are available for both square taper and ISIS bottom brackets, in lengths from about 130 mm to 180 mm in 5 mm increments. They can be found online for about $60, and occasionally less. The ones in the picture are 145 mm ISIS cranks. (Note that the bike comes with square taper bottom brackets, but I found an unusually good price on an ISIS crank and happened to have an extra ISIS bottom bracket.) The cranks have a 110 mm bolt circle diameter, which matched the old cranks, so I just moved the original chainrings over to the new cranks.


I think this is a superior solution for tandem riding with kids. It's not adjustable in length like the crank shortener, which has three different lengths. However, it is possible to buy two Sinz cranksets in different lengths for not too much more than the cost of one pair of crank shorteners. If I did it again, I would do that, getting them in lengths of 145 and 155. Using this approach requires single side drive, but in this era of compact road cranksets and 11-speed gearing, one could theoretically convert even a standard double side drive tandem to use cranks like this without losing much in terms of gearing range.

Bike Friday Tandem Customizations

I already wrote previously about my Bike Friday Family Tandem. I used it for over 2 years in the configuration it came in: flat handlebars with Sachs (now SRAM) 3x7 Dual Drive shifting. I prefer drop handlebars, so last winter I decided to switch out the handlebars.


Switching to drop handlebars on this bike requires a few other changes. First of all, I needed a pair of 3x7 Shimano STI brake/shift levers, which various online sources claim are compatible with the older DualDrive hub/derailleur combinations. Shimano hasn't made a 7-speed shifter for a number of years, so these have to be bought on the secondhand market, but even then they are hard to find because Shimano had already gone to 8 speed on their high end drivetrains when they introduced STI in the 1990s. The one exception is the RSX shifter, which presumably was sold on some lower end road bikes in that era, and comes in a 3x7 configuration. I found these RSX shifters on eBay.


One problem these shifters had when I bought them was that the smaller levers (the ones that shift to a smaller chainring or rear cog) did not engage. This apparently is a fairly common problem with these shifters and it is caused by the old grease getting sticky. I can confirm the claims made by others on the internet that this problem can be fixed relatively easily by spraying degreaser into the shift mechanism a few times, followed by a light lubricant, which eventually frees up the mechanism.


The brakes on this bike (drum brake front, V-brake rear) expect a longer cable pull than STI shifters are capable of generating, so it is necessary to add the Problem Solvers Travel Agent. I've used them on another tandem already and they work great. They come in two varieties, one for V-brakes and one for disc brakes (or drum brakes), so I installed one of each type. Here's the rear V-brake with Travel Agent installed. It replaces the curved "noodle" normally installed between the cable housing and brake.



The disc brake version comes with a hole at the top so that it can be attached to the fork using a cantilever brake mount. This fork doesn't have cantilever mounts, so I attached it to the fork with zip ties and used a piece of inner tube around the fork blade to prevent scratching the paint and hold it in place. So far, braking performance both front and rear with the travel agents installed has been great.



The left shifter, which normally goes to the front derailleur, has worked fine operating the 3-speed internal hub. It takes some getting used to because when connected to this hub, its operation is backwards from a front derailleur: the large lever shifts to a lower gear rather than a higher gear. The combination of the right shifter and rear derailleur has been less than ideal so far. The cable pull for each click isn't quite enough for the derailleur. It's adjusted so that it works OK in the middle of the gearing range, but starts to miss shifts as I get out to the edges. It's possible the derailleur or shifter are just old, but the original grip shifter that came on the flat handlebars worked better.

Sunday, January 13, 2013

Raleigh Tandem With Customizations

I wrote a couple of months ago about acquiring a second tandem. As I noted then, the Raleigh tandems look like a great option for riding with children because they are reasonably priced and can accommodate relatively short riders with just a few modifications.

Fit Customizations

The most important modifications are to get it to fit its riders. The goal was to be able to comfortably fit an 8-year-old on the back and a 5'4" rider on the front. It should be possible based on my measurements of the frame, but the suspension seatpost that came installed in the rear made it impossible to get the seat down as low as I needed. Furthermore, the oversized seat that came on the bike added some extra height of its own.


In the front, the seat went low enough, but the reach to the handlebars was a bit far for a shorter rider, so I wanted to reduce that by moving the front seat as far forward as possible and installing a shorter reach stem. The set back of the stock seatpost on the front limited how far forward the seat could move, so I moved that seatpost to the rear and installed a smaller saddle I happened to already have. The challenge, then, was to find a seatpost for the front with the right diameter and no set back that didn't cost a lot. The diameter turned out to be 29.2 mm, which appears to be common on tandems, but in general is a somewhat non-standard size.


This seatpost made by Origin8 comes in a huge variety of sizes, including the 29.2 mm that I needed. While it didn't matter in this case, it's also very long at 400 mm, so it would be easy to set up this tandem for a very tall rider using the same seatpost. The relatively relaxed seat tube angle of the frame means that putting the seat all the way forward like this will result in a position that will not feel unusual to a rider accustomed to typical road bikes.

The remaining fit-related customizations included the installation of this short reach stem. It's a Profile Design Boa with a 65mm extension and relatively steep angle (45 degrees if I recall correctly), which brought the handlebars in about 8 cm closer than the original stem did.


I also added Ride2 Crank Shorteners to the rear cranks. The pedals are currently installed in the outermost hole, which results in an equivalent crank length of 145 mm. These shorteners were transferred over from my other tandem.


With these customizations complete, the bike was basically ready to ride, but I wasn't done changing things yet.

Optional Customizations

The other customizations made to this bike were purely based on our preferences. I replaced the 26x1.95" tires with more touring-oriented 26x1.25" tires, which are better suited for the type of riding we do. I replaced the stock pedals in the front with different ones that would take toe clips. Heather and I are both used to road bikes with drop handlebars, so I also replicated that setup on this tandem. The existing drivetrain is a 24-speed Shimano setup, so I got a used pair of Shimano Sora 3x8 speed brake/shift levers, Tektro auxiliary brake levers, and a used road handlebar.


Because road and mountain bikes use different shaped cable ends inside the levers, I had to buy new cables as well. The extra cable lengths required for a tandem required that I do a lot of careful measuring before I bought anything so I could be sure everything was long enough. In the end, I concluded the least expensive option was a complete road cable kit plus an extra cable for the rear derailleur. I bought the Jagwire Racer XL kit, which had brake cables that turned out to be long enough for both front and rear brakes on this frame. The derailleur cables were not long enough, but the rear cable was long enough for the front derailleur on the tandem, and for the rear I bought a Jagwire stainless steel cable in a length of 3100 mm.

The linear-pull cantilever brakes (also known as V-brakes) that came on the bike require a longer cable pull than typical road brakes. In order to match the shorter pull of road brake levers with the longer pull required by the cantilevers, Problem Solvers makes this little pulley called the "Travel Agent". The cable wraps around the smaller disc and then jumps to the bigger disk, effectively doubling the distance traveled by the cable as it comes out. The second hole at the top is so that the effect can be reversed if someone wanted to use mountain-style brake levers with road-style caliper brakes. It works great. The Jagwire cables (except for the extra rear derailleur cable I bought) come with a black PTFE coating that makes them super slippery, and all of the braking and shifting on this bike is really solid.


The choice of red accents actually started with the water bottle cages. I was searching online for some inexpensive bottle cages to go on this bike and found something that came in black, gray, and red. We liked the idea of red and bought those, and subsequently got the cables and handlebar wrap in red. I think it looks great with the otherwise monochromatic black, white, and gray color scheme.

Completed Project

Here's the tandem with all of the customizations complete.



The tandem was bought for $200. The most expensive part of the fit customizations are the crank shorteners, which run around $90. Adding a seatpost, stem, and smaller saddle brought the size customizations to a total of around $150. The other customizations probably added more than $200 more, with the shifters being the most significant cost, even buying them secondhand, but the total cost of this tandem is still well below what I spent on my Bike Friday tandem, so I consider it money well spent.

Part Sources

We don't have many bike shops in Champaign, Illinois, and even a bigger city is unlikely to have a bike shop that stocks a lot of the items I've described here, so I do a lot of shopping online for parts. Given Shimano's constant gear inflation, finding shifters for older drivetrains is something that mostly has to be done on the second hand market, and eBay is an important source for that. For the other items, the one source that seems to consistently have almost everything I'm looking for, no matter how obscure, is Niagara Cycle Works, who I buy from through Amazon marketplace. They don't offer super fast shipping, but everything has always arrived by the date promised, the shipping charges are reasonable, and they usually have the lowest available price of the Amazon marketplace sellers, or are close enough to it not to bother buying from someone else.