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  1. #1
    too many bikes
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    The Mauna Kea bike

    I was not happy with the sag in the forks of my DT VIIIFS. Don’t get me wrong … the DT FS is the absolute best 20” folder for the money, but I’m used to adjustable shocks (downhill, MTB, MX). Suspension sag is nominally 10% to 30% of fork travel (and shock travel), and the sag on the BMX suspension fork on the FS was about 80%, nonadjustable. The price/performance of the OEM fork is understandable … but the fork is designed for BMX bikes, and BMX rider weights. The bottom line is I realized that what I loved about the DT FS was the frame and rear shock … everything else could go. Everything but the frame and rear shock did go. I also wanted taller gearing … like 53/9, more length in the cockpit (I'm 6'2", 188 cm), and less handlepost flex.

    I present the “Mauna Kea bike”, a DT FS frame with (see pix, I suggest the MnKea_Wh_Side.jpg pix first):

    an adjustable, carbon fiber fork (MEKS, Hoosier Bicycle Supply), sag set between 10% and 30%, depending on ride profile; the MEKS fork is very popular on ‘bents. White Bros. fork is even better, but I paid $149 for the MEKS, and White Bros. start at $600.

    threadless headset (necessary for the MEKS fork) (dremeled the I.D. of the top nut of Shimano STX headset to an al dente fit; a desperate builder’s trick, don’t try it at home; a compression ring and real threadless headset would probably work, but the MEKS steerer tube is smaller than nominal 1-1/8”)

    sleevepost (sleeve handlepost) like a Swift or Airnimal (Aircraft Spruce, 6061T1 tubing, 1-1/8 and 1-1/4 O.D.s, 0.58 wall, homebrew; smaller tubing is stempost, larger tubing clamped to top of steerer tube and to bottom of stempost using seatpost clamps; inserted star nut in steerer tube, cut a section of the larger tubing to use as a compression spacer, cut the front off of an Icon stem ($1.98 from Pricepoint.com) to use as a steerer tube clamp; sleevepost slips off to pack the bike, a la Swift). Importantly, the stempost rests flush against the steerer tube of the fork, inside the sleeve. This makes the sleevepost very rigid, much more rigid than a folding handlepost, and much lighter. I plan to cut a 180 degree piece from the steerer tube, and the opposite 180 degree piece from the stempost, so that the two will fit together, leaving only the stem to stempost clamp as the source of play/adjustment between the bars and the front wheel.

    double crankset (53/39) (175 mm crankarms, Nashbar/FSA, ISIS drive, with Shimano BB and Speedplay Frog pedals ... 1/4" wider than a folded, folding pedal, but with the advantage of cleated power)

    front derailleur (Shimano R440, SRAM Microshift, homebrew cable hanger, inverted, on hacked FD hanger mounted on the bottom of the seatpost; flange of inside cage arm on FD dremeled to conform to DT swingarm to provide chainline clearance to largest cog from 39 chainring)

    Dura-Ace 9-speed rear derailleur on SunRace RD hanger (biketoolsetc.com) and SRAM Attack shifter

    Shimano Capreo hub and 9-speed cassette (9/26) (Harris Cyclery) on Velocity Razor rim (wheelbuild by J. Gaerlan), Primo Kevlar Comet 1.35 with 1.5 layers of 26” Spinskin, SRAM 9-speed chain

    Shimano 105 front hub on Velocity Razor rim (wheelbuild by J. Gaerlan), Primo Kevlar Comet 1.35 with 1.5 layers of 26” Spinskin

    Euro touring bars (Harris Cyclery) with SRAM 9.0 brake levers, and Nashbar inline brake levers on Nashbar barends with Lizardskins; Nashbar adjustable stem, loosen stem pivot bolt and fold bars against stempost to pack)

    Nashbar and Promax V-brakes, KoolStop pads, Jagwire adjustable noodles, all cable housing replaced with Avenir, all cables replaced with Teflon-coated

    Kalloy suspension seatpost, Vetta SL saddle

    Finally, I have won the battle with the rampworkers at the airports here. That’s not black paint on the bike ... that’s truck bedliner (NAPA). When the bag tossers manage to chip bedliner (they do), I just dab some more bedliner on.

    So…. the only original part is the DT frame.

    Riding impressions
    The bike is VERY fast and comfortable … smoother over bad pavement than a 700c Ti frame with CF seat stays. The Capreo hub is at least 105 quality, maybe Ultegra level. I didn’t think I would notice how much better the bike rolls, but after moving the Primos from the OEM wheels to the Velocity Razors, the difference is noticeable … feels like 1 cassette tooth faster for the same peddling input on the 53 chainring. The sleevepost flex when pulling near the rear of the bars is pretty much like that of a Swift, but when tucked in and pulling on the barends, there is understandably more flex, but still much, much less than the flex of a folding handlepost.

    Almost as stable as my Swift, but more cockpit room due to the barends forward of the Euro bars, better ride than the Swift due to full suspension. The MEKS fork meant I didn’t need a Thudbuster, so I put the Thudbuster on the Swift and put a Kalloy suspension seatpost (adjustable preload, two rider-weight models with the split at 175 lbs; Biketoolsetc.com) on the Mauna Kea bike.

    The 53/9 combination gives 117.8 gear inches, and the 39/26 gives 30 gear inches. Perfect for coastal roads and the climb to Kula.

    For a lower end, e.g., like the Mauna Kea Observatory Access Rd, I put an 11/34 cassette on the OEM hub, Vredstein S-Licks, also with 1.5 layers of 26” Spinskins (I HATE flats, especially on tires that have PIA beads and need 200 psi to set the bead). Change rear wheel, change and adjust RD (Deore LX), and Megarange!, brought to you by the SRAM master link.

    RD shifting is just as fast as on my road bikes. Shifting the FD to the 53 chainring takes care, since there’s an unused third position on the shifter … but the Microshift was the right price and definitely helps to tune the chainline. The rule about working outside to outside, inside to inside, between chainrings and cogs is critically important on this bike.

    I feel I have a high end Bike Friday equivalent (or better) for 1/3 the cost.

    Yan, what a terrific frame! I publicly beg for your FS frame made with Ti. On your next trip to Asia stop by for a test ride.
    Attached Images Attached Images
    Last edited by maunakea; 09-18-06 at 02:57 AM.

  2. #2
    Senior Member Fear&Trembling's Avatar
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    Fantastic work (far too involved for me to ever contemplate). Have you got a picture of it folded/packed?

    Are you running ERTO 406s or 451s? I guess the latter, as 117.8" is tall for a 406" with a 53/9.

    Oh, how much does it weigh now?
    Last edited by Fear&Trembling; 09-17-06 at 05:18 AM.

  3. #3
    Senior Member downtube's Avatar
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    Very cool mods....one more reason for me to go to Hawaii!

    Thanks,
    Yan

  4. #4
    Seņor Mambo
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    Nice ride, mk! Hope you're more kind to the cranks on that beauty.

  5. #5
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    F&T, the wheels are 406. I used "nominal 20" in esteemed Sheldon's gear calculator, since there wasn't a selection for 37-406 (1.35"). A 53/12 combination on a 700c with 175 mm cranks is 116.1 gear inches. The 53/9 combination on the Mauna Kea feels "not quite 53/12, but taller than 53/13" on a 700c. Plenty tall enough for the flats and enough to spin on moderately steep (~5%) downhills. More pix as soon as I see if Wav and Bruce have any pix requests.

    Yan, it would be great if you could visit. I think you would get a kick out of the bike and could improve on my hacksaw and dremel approach (fear and trembling at BF) The same goes for any of the regulars on the forum. Email me at my username atsign teleport-asia.com to let me know you're coming for a test ride and to enjoy the Islands.

    SB, no more demolition derby on this baby, though I still enjoy my figure-8 sessions, now without fork stutter. I particularly don't want to wipe out the D-A RD, so I've stopped the off-road shenanigans. Besides, I have to preserve it for your visit.
    Last edited by maunakea; 09-17-06 at 12:31 PM.

  6. #6
    Hairy Member Crankypants's Avatar
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    I really want to replace the Dahon folding stem on my mini with a similar set-up that you have built up. Looks like a great solution!

  7. #7
    Hairy Member Crankypants's Avatar
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    How much money was put into this project, if you don't mind my asking?

  8. #8
    too many bikes
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    cranky, about $890, excluding the DT FS frame, but including the bedliner and prep solvent, tires, wheels, pedals, and poi gruppo. The biggest expenses were the wheels with Capreo hub (and cassette) and the Frog pedals (combined total about $450 (including excellent wheelbuilding), no discounts or promotions). The rest was collected on promotional pricing over the last 3 months, e.g., Icon stem for $1.98, SRAM Microshift shifter for $7, Dura-Ace RD for $80. Nothing from eBay. All new components. I confess that the Dura-Ace RD is part bling ... but I love that RD. Almost as good as Campy Record.
    Last edited by maunakea; 09-17-06 at 05:39 PM.

  9. #9
    Raleigh20 PugFixie, Merc LittlePixel's Avatar
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    With this bike pr0n you are spoiling us!
    Nice reinvention; Not one to leave outside that one....

  10. #10
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    Just back from a 10 mile ride on the Mauna Kea bike. It's significantly faster than my Swift. Until yesterday, I had been riding the bike with an 11/23 cassette on the OEM wheels, and finally got around to moving the Primos to the Velocity wheelset and Capreo hub. With the 53/9 gearing and better hubs, my speeds were much higher today, and I kept forgetting I wasn't on my road bike and had to correct several times for turn-in as I entered curves at speed. It's funny that before the new gearing and hubs, when riding the modded DT I never settled into a "road bike groove" on my favorite rides near the house.

    The tradewinds are blowing today, which means gusts to 25 mph. The MK bike feels much more top heavy in cross-winds than a road bike, esp. with my seatpost and sleevepost extensions, so it requires different corrective action than the instinctive "road bike reflex".

    No LP, ... this one doesn't stay outside.
    Last edited by maunakea; 11-10-06 at 02:28 AM.

  11. #11
    Air
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    Destroyer of Wheels Air's Avatar
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    Could you talk more about the handlebars? Just ordered a DT and would like to put wider handlebars on it with drops (plus put a top mount indexed shifters on instead of the grip shifters). I'll need to constantly fold and unfold it (as a commuter bike around NYC) - can it still fold up nicely or do the handlebars get in the way?

  12. #12
    Senior Member caotropheus's Avatar
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    The bicycle is almost perfect. You just need to replace the kalloy spring seat post by a Cane Creek air shock seat post

    http://www.canecreek.com/seatposts.html

  13. #13
    too many bikes
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    Air, For the handlebars, see
    http://sheldonbrown.com/harris/handlebars/index.html
    Sheldon calls them "butterfly" bars, but I know them as Euro touring bars ... also commonly used on police bicycles in the EU. You probably don't want these bars if your need a compact fold. Long distance comfort was more important to me than compact fold. I'll snap some pix tomorrow for you and F&T of the "compact form".

    Cao, in fact, I did have a TB/LT on the bike, see
    Announcing: the DT FS TB
    but the new fork is so good that I moved the TB/LT to my Swift, which needs it much more than the MK bike.
    On the MK bike, I needed a seatpost plus the seat tube to get the saddle to pedal distance I need, and the Kalloy is well worth $30 vs. a plain seatpost for a few dollars less.
    Last edited by maunakea; 09-17-06 at 11:59 PM.

  14. #14
    Senior Member Fear&Trembling's Avatar
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    F&T, the wheels are 406. I used "nominal 20" in esteemed Sheldon's gear calculator, since there wasn't a selection for 37-406 (1.35"). A 53/12 combination on a 700c with 175 mm cranks is 116.1 gear inches. The 53/9 combination on the Mauna Kea feels "not quite 53/12, but taller than 53/13" on a 700c.
    That sounds about right - with Comets on 406s I reckon a 53/9 will be about 112".

    Let us know how that Capreo cassette gets on. I am getting rid of my Birdy and will prob go for a Capreo upgrade on a single ring/20" machine.

  15. #15
    too many bikes
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    F&T, Will do. I'll shoot some more pix tomorrow.

  16. #16
    All ur bike r belong Enki james_swift's Avatar
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    Oh man...Dura Ace on a DT...that's like the guy that buys a Civic to drop-in an Acura engine. It's amazing that you have that much bling on the bike, and still come-out cheaper than a similarly equipped Friday, and still have top-notch suspension. Definitely not another bike like yours on the entire planet.

    Massive props for your wrenching skills, man. BTW, could you help me out with a how-to on that home-brew stem-post? I'd like to make a custom one for my Swift, as I'm not sure about making the commitment to chop mine down...in case..that is, IN CASE, I decided to sell the bike when the steel Swift 2.0 comes out.

  17. #17
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    Quote Originally Posted by maunakea
    F&T, the wheels are 406. I used "nominal 20" in esteemed Sheldon's gear calculator, since there wasn't a selection for 37-406 (1.35"). A 53/12 combination on a 700c with 175 mm cranks is 116.1 gear inches. The 53/9 combination on the Mauna Kea feels "not quite 53/12, but taller than 53/13" on a 700c. Plenty tall enough for the flats and enough to spin on moderately steep (~5%) downhills. More pix as soon as I see if Wav and Bruce have any pix requests.
    Wooo hooo Mighty Maunakea!!! Finally, some damn pics!!!... ahhaaha... Mahlo!! great use of the dremmel tool and a fine finished product!! ... my pic request would be to set your camera on self-timer and see a pic of you with the Mauna Kea held triumphantly high overhead! .. possibly with island girls in the backround..

    Bruce

  18. #18
    Bromptonaut 14R's Avatar
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    As I said before, if you want a good, not really expensive bike, get a Downtube. If you want a really good and expensive bike, get a Downtube and upgrade it.

  19. #19
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    All,
    Thanks for the warm reception for the MK bike and the compliments.

    james,
    When I shoot more pix, I'll do some on the sleevepost details. You won't have any trouble adapting the sleevepost design to your Swift. There's a cross-member in the sleeve that must fit into a notch in the top of the Swift steerer tube. For the cross-member, you could try to press-fit a bolt, or better IMO, JB Weld a bolt in place (or use a seatpost clamp bolt). The stem post is steel on my steel Swift, so using Al tubing will save some weight, but may flex a bit more. If you sell your current Swift, you simply remount the OEM stempost.

    The Dura-Ace RD is, in part, my way of complimenting Yan on the best 20" frame on the market. Rafael is right, and yes, an upgraded DT FS could eat a significant piece (most?) of BF's lunch. A Ti frame with an air shock, hmmmm good.

    Bruce,
    More pix on the way. I'll see if the 7 year old girls next door are willing to get near the bike. They think bikes are icky and that they will somehow sweat (very icky) by proximity effect.
    Last edited by maunakea; 09-18-06 at 02:19 PM.

  20. #20
    All ur bike r belong Enki james_swift's Avatar
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    Quote Originally Posted by maunakea
    All,
    Thanks for the warm reception for the MK bike and the compliments.

    james,
    When I shoot more pix, I'll do some on the sleevepost details. You won't have any trouble adapting the sleevepost design to your Swift. There's a cross-member in the sleeve that must fit into a notch in the top of the Swift steerer tube. For the cross-member, you could try to press-fit a bolt, or better IMO, JB Weld a bolt in place (or use a seatpost clamp bolt). The stem post is steel on my steel Swift, so using Al tubing will save some weight, but my flex a bit more. If you sell your current Swift, you simply remount the OEM stempost.
    Looking forward to it. Could you tell me where you bought the aluminum tubing for the stempost and what dimensions?

    Thanks!

  21. #21
    too many bikes
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    Per requests for the folding process, with pix (below).

    1) Loosen pivot bolt on adjustable stem. Note that the lateral displacement of about 5 mm before the bolt head is tapped to disengage the splined bracket from internal splines of the stem. With the bracket free of the internal splines, the stem can be pivoted down.

    2) The top and bottom clamps on the sleevepost are loosened, which permits the stempost to slide out of the sleevepost, and the sleevepost to slide off the steerer tube. There are separate pix of the exposed steerer tube, the sleevepost, and the star nut in the steerer tube. Not shown is a section of the larger tubing cut to serve as a big compression spacer to tension the headset. (Also not shown are all the dremel cut-off bits I went through.) The steerer tube clamp (a hacked MTB stem) is not loosened, so the forks are undisturbed. This is very similar to the Swift and Airnimal setup, only they use “real” steerer tube clamps.

    3) In the shot of the folded bike, I didn’t bother to remove the wheels … nothing special there. I put extra cable to the controls to permit flexibility in packing the bike. The handle bars and stempost tuck nicely into the space between the front wheel and the stand. The sleevepost, seatpost, and saddle can be tucked within the rough outline of 36” x 18.5”. The folded bike still fits in the DT bag. The tape does run to the back of the rear tire… the photo angle is deceiving.

    The Al tubing is from Aircraft Spruce.
    www.aircraftspruce.com

    The smaller tubing for the seatpost and stempost is
    03-37000-1 6061T6 TUBE 1-1/8X.058 1FT.

    The larger tubing for the sleevepost and compression spacer is
    03-37300-1 6061T6 TUBE 1-1/4X.058 1FT

    Each foot of tubing is about $3.00…. plus postage.


    The MK bike is a terrific ride, very close to road bike torso position and absolutely the same as road bike leg position. The 53/9 gives me plenty of top end for the flats and downhill, and the combinations off the 39 handle any hills, with luggage. The Capreo is really well designed (9, 10, 11, 13, 15, 17, 20, 23, 26). It deserves the D-A RD. The straightest chain lines are 39/10 and 39/11, which are great campus and shopping center gears, and 53/9, the flat-out gear. Like a Swift or Airnimal, the MK bike doesn’t have the quick fold of a hinged handlepost …. but I spend a lot more time in the saddle than folding, so that tradeoff was easily made.

    If the riding profile were office worker, you could probably get the MK bike acceptably small for a cubicle by sliding the sleevepost off, slipping the bars under the folded bike, sliding the seat post out, and putting the seatpost by the bars, pretty close to one of the pix below except the stem is pivoted in the pix below, and at the office you wouldn’t need to deal with a 5 mm hex key for the adjustable stem.
    Attached Images Attached Images
    Last edited by maunakea; 09-19-06 at 04:22 PM.

  22. #22
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    Bike looks great-lots of hard work.

    What are the possibilities of putting an internal hub on that FS?

    Marman

  23. #23
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    Quote Originally Posted by Marleetet
    Bike looks great-lots of hard work.

    What are the possibilities of putting an internal hub on that FS?

    Marman
    I've done it to mine, but mostly because I use it off pavement frequently while running my dog on trails in the hills..

    Bruce
    Attached Images Attached Images

  24. #24
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    My Swift has a gear hub, so I stayed with an RD on the MK bike... but as Bruce shows, it can be done. I'm waiting for the i-Motion 9 to u/g the Swift.

  25. #25
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    Bruce- Thanks for the picture. I assume the add on is some sort of tensioner: what kind?

    (By the way- I only got your email asking if I got your answer- I never got any others)

    Marman

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