USS Yiggy (version 1.1), a Trek Y 26 CruzBike Conversion

Discussion in 'Conversion Kit Brag Board' started by Charles.Plager, Mar 11, 2014.

  1. SamP

    SamP Active Member

    [Some sections of this to be completed later]

    USS Yiggy


    Revision 1.0 was the first ridable version, after I mounted the front derailleur and other bits I I'm calling this revision 1.1.


    USS Yiggy [1] started as a somewhat non-stock 2004 Trek Y 26 I picked up via Craigslist. I believe it is a size small frame ?though there are inconsistencies compared to the measurements listed in the technical documentation. However, the important measurement, the standover height, matched the small size. The tires weren't stock and at least one of the wheels was non-stock.

    My bike mechanic skills at the start were just above complete novice, but I decided I would do (most) of the work instead of hiring a bike mechanic to do the conversion. There's a co-op bike shop nearby where I could use their tools and volunteers would give guidance on how to do various procedures. I also found a community bike shop (run as a youth program by the county) with a stock of used parts for cheap. I also have a hybrid bike which recently (January) got new tires, tubes, crankset, and chain which I was willing to raid for parts.

    Original Trek Y 26


    Full suspension Y-frame mountain bike, 26" standover, aluminum frame, cromoly rear swing arm, suspension fork with 70mm travel, 1 1/8" threadless headset, 7-speed v-brake/trigger shifters, top pull triple front derailleur 31.8mm clamp, 42/34/24 crankset, 73mm x 122.5mm square taper axle bottom bracket, 7-speed rear derailleur, 7-speed 11-34 (11/13/15/18/22/26/34 -- that's some granny gear) cassette, 31.6mm seatpost, 26x1.95" front tire (knobby), 26x2.2" rear tire (even more knobby), about 36 pounds (tech manual claims bike should weigh 31 pounds)

    The obvious problems to be worked around were the seatpost, bottom bracket width, front derailleur clamp, and the tires were quite unsuitable for a mostly road bike. I bought a new 68x122.5mm bottom bracket, a new 31.6mm to 27.2mm seatpost shim, and a used 27.2mm seatpost (with a 7/8" top) from the community bike shop.?

    US Yiggy (Rev. 1.1)

    Side view (same image as above, just scaled down a bit)


    I left the cables somewhat long so I could experiment with forks and handlebars/stems. I'm not too happy with the kickstand, it doesn't seem to fit all that well and I used some rim tape to keep it from wiggling around. I put that bottle cage (snatched from my other bike) on the steering tube riser yesterday using electrical tape to try it out.

    The much smoother tires (and tubes) are swapped from my other bike. They're practically brand new, purchased in January.

    Rear view

    alt="Back" [​IMG]

    Not much of interest here, two Zefal bottle cages I got from CruzBike and a saddle bag to hold my wallet and keys, I'm on the lookout for better storage options. I'm probably going to get a Topeak MTX BeamRack seatpost mounted rack since I already have one of their MTX bags, but something a little larger on the seatback would be nice as well.



    Those blue things holding the derailleur cable to the fork and wrapped around the cables are Nite Ize GearTies in 6" and 12" lengths. They're basically rubber coated steel wires which are flexible but hold their shape so they can be wrapped around stuff and stay in place. A little bulkier and more expensive than zipties, but they're easily unwrapped and reused/repositioned and don't slip. The excess cable lengths are pretty obvious here.

    The cockpit


    The cockpit is actually pretty cramped with the bottle cage (which isn't quite centered, oops) on the steerer extension tube, it's just taped on for now, it was much handier than trying to get bottles out from the back of the seat.

    The smartphone is in a Topeak SmartPhone Drybag 4". The angle is rather shallow and tends to reflect the sky. The phone is a Sony Xperia Pro, a 2011 Android phone with built-in ANT+ support, which I use for my heart rate monitor strap and a Garmin GSC-10 speed/cadence sensor, along with the IpBike bike computer app. Several of Sony's 2011 phones had ANT+ support, it wasn't until late 2013 that newer phones with ANT+ support started appearing from Samsung and Sony.

    An Original Incredibell is tucked in on the right with the sounding lever conveniently reachable between the two triggers. A little Seattle Sports Blazer light is tucked behind the phone, it doesn't do much to light things up in front but is easily visible in twilight conditions. Oh, the red thing on the left is a rubber band I use to lock the front brake when I'm parking the bike. And not to forget the Zefal Spy Mirror I got from CruzBike along with the Conversion Kit.



    The rather ugly rim tape gives the kickstand something to bite into without (hopefully) damaging the surface.

    Seat pan mounting


    I've used heavy duty zipties (good to 175 pounds each) to mount the seat pan. I didn't want to bother with the pipe clamps while I'm still experimenting. The front mount point is too long for the pipe clamps included with the kit.

    Rear derailleur


    Again zipties instead of the kit's pipe clamps and the GearTie works a lot better than the ziptie I initially used. The ziptie kept on sliding around on the frame. Note the huge low gear (34 teeth) and big gap to the next gear up (26 teeth). In the lowest gear/small chainring the speed is so low it is very difficult to balance. Just barely visible is a washer on the outside of the FWD bracket on the quick release skewer, without it the wheel often moved along the dropout when under stress.

    Speed/cadence sensor


    There's the Garmin GSC-10 speed/cadence sensor. I believe there are very few recumbent bikes that a combination sensor would work on. My (not pictured) heart rate strap is a Motorola MOTOACTV model which was the cheapest I could find at the time (about $35 on Amazon, though prices are up now).

    Kit assembly difficulties

    During a first test assembly, I discovered that the dropouts on the FWD brackets installed on the original front fork were too narrow and eventually decided that the fork or its dropouts were slightly warped. I eventually assembled the bike with a rigid fork acquired from the community bike shop (the second one from there, I originally got a fork which I eventually realized was for a 29er when the brakes were completely wrong). I've mounted and dismounted the forks and FWD drive brackets a bunch of times and the bolts and nuts show it (I've bought some tools so at least I'm not using adjustable crescent wrenches anymore).

    The FWD brackets aren't bent quite right which was more of a problem earlier on since it combined with the original front fork problem. Fortunately the brackets are off almost identically which causes the wheel to be angled slightly to the left if you mounted the wheel exactly the same spot in the dropouts. I compensate by adjusting the wheel position in the dropouts a bit.

    The seat edge protector on the seat pan tended to slide off, especially at the ends. I used a bit of electrical tape on the ends of the protector, looks like I'll have to add some more tape as the edge protector partially came off on my first long ride (but the ends stayed on).

    I lost a few bits over time.

    The pivot clamp bushing fell out and went who knows where (didn't notice it was gone for awhile) probably when I dropped the TFT sleeve on the co-op bike workshop floor. I thought I had lost the other one as well but found it in the back of my car. I went looking for replacements and it looks like some Trek bikes used bushings of the same dimensions (only possible to measure since I found one I thought I had lost). Eventually I got a replacement from CruzBike.

    One of the lock nuts and accompanying washer holding the seat bottom to the seat back went missing during transport. Found usable replacements at Home Depot, though the washer is a lot smaller outer diameter.

    The velcro strips applied to the seat back didn't stick well, one disappeared during transport (I usually remove the seat cushions when transporting the bike so they don't get soaked by road spray). I bought sticky velcro strip from Lowes. The replacement strip is wider than the velcro in the kit and seem to stick a lot better.


    After I discovered the original front fork was warped, and before I bought the rigid fork, I bought a new low end previous generation suspension fork on clearance from REI (a Rock Shox Dart 2). It looks like it would be great except for the disc brake mounts getting in the way. I've spent some time cutting and grinding with a dremel-clone and finished working on it today. Now I think it should mount, so sometime soon I'll have a full suspension bike.

    I've picked up a used cruiser-style handlebar and stem from the community bike shop. I'll give that a try, probably at the same time I mount the new suspension fork.

    I'll probably keep a bottle cage on the steerer extension tube with a better mounting. I wonder how well the Profile Design AquaRack (I see one on Craigslist) would work here, though I"m a bit leary of adding even more weight high up to the front triangle. Maybe if I mounted it lower but on the front side of the tube.

    I'm going to swap the pedals from my other bike, so I'll have toe clips on the Yiggy. (Alternately, I may buy a set of used pedals with toe clips from the community bike shop, I know I've seen them there).

    I may attempt to bend the FWD brackets so the bends are correct.

    Seatpost mount rack (likely Topeak MTX BeamRack) and more storage bags (saddle or other).

    Wish list (much farther future and speculative)

    The hub is an 8-speed hub (not the stock hub for the Y 26) so I'm contemplating changing the cassette and rear shifter to get a more low gears instead of the large jump between the first and second gear (34-26) I've currently got.

    I'd like to get larger chainrings, currently my big chain ring is a 42 tooth. The front derailleur was specifically made for the 42/34/24 chainring set I've got, I wonder how well it would work with a different set of chainrings.

    Alternately (or in addition!) an in gear hub.

    Electrification! Hub motor in rear wheel. The em3ev kits look interesting

    Detailed specs

    Aluminum Y-frame, size small, 26" standover height
    Cro-moly rear triangle, rigid fork
    Mozo RS-200 rear shock
    Cane Creek Aheadset VP-A76C semi-cartridge 1 1/8" threadless headset
    Shimano EF29 3x7 speed brake/trigger shifter
    Shimano FD-C050 top pull front derailleur
    Shimano Acera-X rear derailleur
    SR XCC-150 triple crankset, 42/34/24
    73mm width x 122.5mm axle square taper bottom bracket
    Shimano HG050 Megarange 11-34 7-speed cassette, 11/13/15/18/22/26/34
    Alloy linear pull brakes


    CruzBike Conversion Kit, $395 (CruzBike)
    2004 Trek Y 26 size small, $150 (Craigslist)

    Rigid fork for 26" wheel, used, $10 (Phoenix Bikes) [fork on Y 26 was warped]
    Shimano BB-UN55 68mm/122.5mm Square Taper Bottom Bracket, $29.99 (Performance Bike) [stock BB was 73mm]
    Cane Creek 27.2mm to 31.6mm Seatpost Shim, $17.50 (eBay, including shipping) [Y 26 has 31.6mm ID seat tube]
    27.2mm Seatpost, used, $5 (Phoenix Bikes)

    Vittoria Randeneur Cross tires, 2 x $35 (from other bike, purchased recently from REI) [tires on Y 26 were very not road tires]
    Novarra Schrader Tube, 2 x $7 (from other bike, purchased recently from REI)
    Rim tape (A1 Cycling)
    Clarks Zero-G (Shift) Cable Kit, $24.99 (Performance Bike) [incorrectly cut cables that came on bike]
    Giant E-Series Brake Cable Kit, 2 x$9.99 (A1 Cycling) [incorrectly cut cables that came on bike]
    SRAM PC 850 8-Speed Chain, $15.99 (Performance Bike) [needed longer chain than came on bike]

    Nite Ize 6" GearTie 2-pack, $2.98 (Home Depot) [tie cables together to keep them neat and away from legs]
    ?Nite Ize 12" GearTie 2-pack, $3.97 (Home Depot) [tie rear derailleur cable to fork leg]
    UtiliTech ?15-Pack 24" Nylon Cable Ties, Outdoor (UV Protected), 175 pound tensile strength, $7.24 (Lowes) [used instead of pipe clamps on FWD bracket and seat pan]

    Total $766.64 (before replacing lost parts, excluding tax and shipping for conversion kit)

    Pivot clamp bushing, $5 (CruzBike) [replace lost part]
    Lock nut, M6-1.0mm nylon insert zinc plated, PN 594 654, $0.43 (Home Depot) [nut and washer used to connect seat bottom to seat back lost while transporting bike, I guess it wasn't tigthtened correctly]
    Washer, 5-pack M6 Class 10 zinc plated, PN 329 179, about $0.50 (Home Depot)
    Velcro 5' x 3/4" Black Universal Sticky Back Roll, $6.97 (Lowes) [one of the hook strips on seat back lost while transporting bike]


    Kickstand, $5 (Craigslist)
    Zefal Spy Mirror, $14 (CruzBike)
    Zefal Spring bottle cage x 2, $!6 (CruzBike)
    Mirrycycle Original IncrediBell, $11 (REI)
    Topeak Smartphone Drybag 4, $24 (REI)
    Garmin GSC-10 ANT+ Speed/Cadence sensor, $36.99 (Amazon)
    Sony Ericsson XPERIA Pro [supports ANT+ sensors]

    [1] Trek (Star Trek, hence USS) Y (chemical symbol for Yttrium) 26 (atomic number of iron)
    YIG [Yttrium Iron garnet] has some interesting properties and is used for various technological applications.
    Yiggy is defined by the Urban Dictionary as someone with reckless intentions .
  2. Charles.Plager

    Charles.Plager Recumbent Quant

    Nice write up. You're

    Nice write up. You're learning a lot with this bike. :D

    I'm a little worried about the zip ties holding the conversion kit to the fork. Keep an eye on those (at least). For the seat pan, your weight and the seat post should help keep it in place.

    Now let's hear about riding Yiggy!
  3. SamP

    SamP Active Member

    Zip ties on FWD bracket

    As far as I can tell they are there to minimize movement and hold in the stuffing (cut up bike tube). I didn't even have anything there until a few days ago, just some electrical tape to prevent the FWD bracket from scraping the paint off the front fork. The natural tendency is for the FWD bracket to push on the fork at that point, not pull away. I suppose bumps could cause pull away transients. Anyway, the zip ties are so I wouldn't have to bother with the pipe clamps while I was still experimenting, I'll use the pipe clamps here and on the seat support later.

    A ride report will be forthcoming, I did about 20 miles Sunday and had my first actual crash (fortunately at fairly slow speed)
  4. hurri47

    hurri47 Active Member

    conversion/sofrider storage

    The Angletech Aeropod fits the Cruzbike seat perfectly and holds enough crap to weigh you down if you don't watch out. It's costy, though, unless you find a used one.

    Here is mine on my converted Cannondale. (As you can see, you're not the only one not shy about excessive cable length.)

  5. SamP

    SamP Active Member

    Storage options

    Yep, moderately pricey. I actually already have a Topeak MTX TrunkBag EXP which actually has a larger nominal capacity, so I'm definitely leaning towards getting a Topeak seatpost mounted rack. I'm intrigued by the Silvio under seat storage idea. I'd also like some accessible during ride storage (for snacks and maybe a few other items).

    1. handlebar:: not much space available with this handlebar, new cruiser-style handlebar may have more space
    2. stem: already being used by smartphone mount
    3. steerer extension tube: I'll probably make some water bottle holder permanent, but there's more space around the tube
    4. telescoping front tube: I remember seeing a post which used a top tube bag here, but that's not really accessible during the ride.
    5. top tube: not much space there, though I can move the seat pan back an inch or so
    6. under seat:a side-entry clip or box/bag could be mounted to the bottom of the seat on either or both sides (basically a variant of the Silvio under seat storage idea)

  6. Cruzbike Chris

    Cruzbike Chris Active Member

    I have the topeak seat post rack and love it

    Hey Sam, good looking conversion. You went thru basically the same thing I did. I have the Topeak MTX BeamRack and carry a water bladder, keys, phone and spare tube with tools in mine and wouldn't ever go back to water bottles. I also have the Y26 and finally upgraded about a year ago to drop bars and 9 speed but also went with the 11/34 and upgraded the chain rings to 26/39/50 a lot like Charles. You will love this bike the more you ride it. I am in the process of converting now to 700 so stay tuned. Pictures to follow.
  7. SamP

    SamP Active Member

    I meant to post on this last summer, but Yiggy 1.2 has the fork, stem, and handlebar mentioned in the post on the Conversion Kit board. Also, I swapped the pedals with my other bike so i got better fitting toe clips.

    Late fall I had a slow speed crash which resulted in the large chainring getting noticably bent. I'm not sure if it was the crash or all the manhandling I did to get the chain out from between the charinring and the crank. A local LBS bent it back but it was far from perfect, you could see it wobble a bit and shifting was much worse. I ordered a Shimano M361 170mm 48/38/28 crankset a few days ago and hopefully arriving next week, I may fiddle with stem and handlebar while I'm at it for Yiggy version 1.3. I'll probably have to increase the length of the chain, the current big chainring is 42 teeth, not sure how to do that. Hopefully I won't need to change the front derailleur (which the specs claimed were specifically designed for the 42/34/24 chainring set)

    Near future possible upgrades:
    * change out to an 8-speed cassette (this would also require I change the brifter)
    * clipless pedals?
  8. Charles.Plager

    Charles.Plager Recumbent Quant

    Sorry about the fall. Been there.

    Most front derailleurs are terribly under-specked. The original derailleur that came with my Sofrider and the 48/34 works beautifully with my 48/38/22. After you get your new derailleur setup, see how much room you have and consider dropping the granny gear back down to 24 or 22.

    Clipless pedals are scary to think about if you've never used them. I grew up using toe clips and have had them on everybike I can remember owning (except my folding bikes).

    My Sofrider was the first bike I ever used clipless pedals on. And it makes a HUGE difference. It makes it much easier for your legs to control the front of the bike (I can ride with no hands without clipping in, but I'm not sure I ever would have learned if I wasn't clipped in). I'm not going to argue that they are more efficient (I think they do allow me to "scrape the mud of my boot" more than many pedals, but whatever), but I am going to argue that they are a lot more comfortable. Not having to hold your feet on the pedals really saves a lot of effort.

    And, I've had a couple of Whoops, crap moments where I've tumbled over (once with my son on the attached trail-a-bike). But in all cases, the only thing that was hurt was my pride.

    Good luck. And don't forget to report back sooner this time! :D

  9. hurri47

    hurri47 Active Member

    The guy who built up my converted Cannondale left all the original MTB gearing intact. I would spin out on even the mildest downhill, so bigger rings were my first priority. I let my LBS do the work, and they found a Shimano Alivio that not only had the right geometry, but also fit the boom and pulled from the correct direction without needing a reverser. I wound up paying around $100 for a complete new triple crankset and front derailleur, installed.

    (I do not understand my LBS labor rates unless the idea is to make them so attractive I won't be tempted to do the work myself).


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