Results 1 to 38 of 38
  1. #1
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518

    Fatback build project

    I am custom building a Fatback frame. I am going to take my time doing it and document it, weigh parts, make a vlog, etc. I am a bit of a weight weenie, so one of the goals in the choice of components (but not the only one) is weight. I am waiting for the upcoming 616fab hubs to complete the build anyway. For those not concerned about weight, please do no thread jack by posting how you don't care about weight. Yeah, it will happen anyway, but I have to try.

    Other parameters of the build: some of the parts will be moving over from my current Fatbike, which I am still riding all the time, so those parts will be delayed to the very end of the build. The primary use of the bike is sand/beach riding in Southern Calif. I do want to play with it in the snow occasionally, but it will probably never see AK cold. I also take my fatbike on regular trail rides, too, but not all that often.

    So lets get started, shall we?


    The frame is the 2012 Fatback Alloy Made in USA frame. Size 18", black ano, tapered head tube. It tips the scale just under 4 pounds (3 lb 15 oz) with no seat post clamp, which is not included with the frame. This weight does include the derailleur hanger and water bottle cage bolts. Those pieces weigh 1 oz for comparison.


    The fork looks amazing. It is carbon with a tapered carbon steerer. Uncut, it tips the scale at 798 grams. It also has native post mounts, which I like from a weight standpoint, it means an IS-Post mount is not needed, since most brakes are native post mount anymore.


    The Origin 8 Torq Lite seatpost clamp has a unique shape, I will get better pics as the build goes. I think the shape is supposed to act like a partial sleeve to reinforce the top of the seat tube.


    Origin 8 Ultim8 seatpost is feathery, and the shape of the Fatback frame means less exposed seatpost, so this 300mm 30.9mm diameter seatpost will be plenty long enough.


    Here it is on the stand, ready for the next step
    Disclaimer: ComCycle USA

  2. #2
    All fat, all the time.
    Reputation: Shark's Avatar
    Join Date
    Feb 2006
    Posts
    7,173
    Ar you going SS or 1x to help shave weight? What rims?

  3. #3
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    All will be revealed as I go. But I am going with full gearing, brakes, etc. No SS, fixie, etc. business. And drilled Rolling Darryls.

    Quote Originally Posted by Shark View Post
    Ar you going SS or 1x to help shave weight? What rims?
    Disclaimer: ComCycle USA

  4. #4
    mtbr member
    Reputation: bighit's Avatar
    Join Date
    Feb 2004
    Posts
    2,524
    That looks sexy already.
    2013 mongoose Fat bike
    2012 Moonlander.

    http://undergroundvelo.proboards.com/

  5. #5
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518

    The project continues...

    The build continues. This is it so far:




    The fork is partially cut, I will adjust the stem position by swapping spacers around and do a final cut after riding it a while. The Sunline stem is not being made anymore, too bad, I like it. I like wide flat bars, SRAM's Noir T30 was a bit of a splurge, it includes its own bar end plugs, which is kind of cool. FSA headset and compression bolt hold things together as I go.


    I have an old Gobi saddle around, I like these saddles, and it will add a bit of color to the bike.
    Disclaimer: ComCycle USA

  6. #6
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    Here are a bunch of weights

    Older Gobi Saddle


    Compression bolt, which I am using:


    Star nut/top cap combo. I am not using it, but it is interesting to compare with compression bolt (shows 26g)




    Sunline XC-1 stem, discontinued model


    E13 Snowbike crank, no bb cups


    E13 Snowbike crank with cups and spacers, reads 873g
    Disclaimer: ComCycle USA

  7. #7
    Fat!Drunk!Slow!
    Reputation: JordyB's Avatar
    Join Date
    Oct 2007
    Posts
    1,454
    Nice work on all the weights!!! Keep it coming!

  8. #8
    A Surly Maverick
    Reputation: Dr Feelygood !'s Avatar
    Join Date
    Jun 2006
    Posts
    2,593
    This build is making me drool

    Darth Fatbike takes shape !
    A Fatback'd Lefty for who life IS a Beach

  9. #9
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    Thanks. I am thinking I need to swap a black saddle onto this bike. My magura brakes are silver, not sure how that will work out, I may have do a double swap to get my black set on this bike, too. I have black XT components that will start to show up in the next couple of steps. Like I said above, the 616fab hubs are the bottleneck for completing the bike. 616 has lots of droolworthy pics of them up, I don't think I will have to wait too long for them.
    Disclaimer: ComCycle USA

  10. #10
    mtbr member
    Reputation:
    Join Date
    Nov 2009
    Posts
    381
    would a phil wood bb and middleburn crankset work out lighter - i think they would - thats what i use

  11. #11
    All fat, all the time.
    Reputation: Shark's Avatar
    Join Date
    Feb 2006
    Posts
    7,173
    Quote Originally Posted by DirtDad View Post
    All will be revealed as I go. But I am going with full gearing, brakes, etc. No SS, fixie, etc. business. And drilled Rolling Darryls.
    Cool, I was just curious. Going by your description of a WW build & mainly beach riding, figured a 1x would be about perfect! 30T up front & a 11-36 out back you'd be set.

  12. #12
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    My beach riding includes the coarse sand you sink into even when its wet, deep dry stuff, rock piles, and a steep cliff access trails. I need granny, clipless pedals, and a smooth spin.
    Disclaimer: ComCycle USA

  13. #13
    aka bOb
    Reputation: bdundee's Avatar
    Join Date
    Feb 2008
    Posts
    7,905
    Are you going BFL's?

  14. #14
    mtbr member
    Reputation:
    Join Date
    Sep 2004
    Posts
    187
    Quote Originally Posted by DirtDad View Post
    All will be revealed as I go. But I am going with full gearing, brakes, etc. No SS, fixie, etc. business. And drilled Rolling Darryls.
    Does this mean the unbuilt wheelset you have listed in the classifieds is no longer available? If it is, let me know how much shipped to 80027 unbuilt.

  15. #15
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    I have one BFL, I know it will fit on the front. That will give me a chance to install it on the rear and see how much clearance I have. If it fits, I will buy another one. Otherwise I will use a Larry in the rear (which I also have).

    A couple more weights and black components:




    With those parts installed. Not dramatic progress. I will make sure to wipe the camera lens next time.


    2 notes. When installing a direct mount derailleur, it has to be installed before the drive side crank arm. The frame mount holes are just not reachable once the crank is in place.

    Also, this is pretty much all I can do for a while. Some of the parts I need are being moved over from a working bike that I am riding a lot. Plus, I am waiting for 661 fab hubs (as I said before, but just in case you dont read every post). Once the hubs arrive, I will build the wheels. Then, finally, I will move over all the bits from the donor bike to complete the build. If I get bored, I may weight a few parts, I guess.
    Disclaimer: ComCycle USA

  16. #16
    aka bOb
    Reputation: bdundee's Avatar
    Join Date
    Feb 2008
    Posts
    7,905
    Yeah I didn't have good luck. E13+Fatback+bfl=5 maybe 6 cogs unless you take one spacer from non drive side and install on drive side. I didn't do it not enough threads. Now Fatback crank+Fatback+bfl=8. Of coarse just my experience and this was with a 9 speed cassette.

  17. #17
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    Which rim?

    Quote Originally Posted by bdundee View Post
    Yeah I didn't have good luck. E13+Fatback+bfl=5 maybe 6 cogs unless you take one spacer from non drive side and install on drive side. I didn't do it not enough threads. Now Fatback crank+Fatback+bfl=8. Of coarse just my experience and this was with a 9 speed cassette.
    Disclaimer: ComCycle USA

  18. #18
    aka bOb
    Reputation: bdundee's Avatar
    Join Date
    Feb 2008
    Posts
    7,905
    Quote Originally Posted by DirtDad View Post
    Which rim?
    Ooops good point, I forgot that! Uma 90's.

  19. #19
    A Surly Maverick
    Reputation: Dr Feelygood !'s Avatar
    Join Date
    Jun 2006
    Posts
    2,593
    How goes the project DD ????
    A Fatback'd Lefty for who life IS a Beach

  20. #20
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    It was awaiting new 616 fab hubs, spokes, and a new TS 2.2 wheelbuilding stand that can handle 170mm hubs. All is in hand now, the project will spool back up soon now.
    Disclaimer: ComCycle USA

  21. #21
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    The wheelbuild is the next step. I have been waiting on the parts, now I have them.

    I had hoped to get 2 drilled Rolling Darryls in this weight range. But after looking at many here and elsewhere, it seems that most of them weigh a bit more than this one. Maybe Surly made some running change to the rim?


    All of the other rims I found weigh within a few grams of this:


    Ever wonder what 64 Super Comp, Black, 264mm spokes weigh, including spoke prep?


    The new 616fab hubs look nice:




    And just for the sake of completeness, 64 alloy nipples.
    Disclaimer: ComCycle USA

  22. #22
    A Surly Maverick
    Reputation: Dr Feelygood !'s Avatar
    Join Date
    Jun 2006
    Posts
    2,593
    Very Impressive hub weights !

    RD's also looking good at < 850g
    A Fatback'd Lefty for who life IS a Beach

  23. #23
    aka bOb
    Reputation: bdundee's Avatar
    Join Date
    Feb 2008
    Posts
    7,905
    You could always get the un-holy rd's drill them with 1.5" holes and get em down to the 750's. Liking this project a lot, thanks.

  24. #24
    mtbr member
    Reputation:
    Join Date
    Nov 2010
    Posts
    85
    Quote Originally Posted by DirtDad View Post
    The new 616fab hubs look nice:
    Do you have them in sotck at ComCycles?

  25. #25
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518

    Complete undressed wheels

    Base wheel build is complete. The is the bare wheels only, no rim strips, rotors, skewers, etc. One nice thing about the 616fabs is they do not need skewers, you can use lighter end bolts instead.




    Front wheel




    Rear wheel

    The wheels could be lighter with Large marge lights or revo spokes, for example, but I am looking for more floatation and gearing than that.
    Disclaimer: ComCycle USA

  26. #26
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518

    More parts for the wheels

    Next step: add parts to the finished bare wheels:


    Rim strip, Rolling Darryl sizes



    Shimano RT97 rotors. Nice that these are alloy in the middle and have an alloy lockring, which resist corrosion well.



    This is a Kenda 26 x 2.7 tube, marketed as a QBP "SL" model. I have had good luck with these. As long as the thickness of the tube rubber is consistent (and it is on these tubes), they overinflate just fine. These don't pinch down around the valve either. I have tried overinflating tubes from WTB and other brands without any success, by comparison.


    The 616 Fab hubs take these hub bolts (I think regular QRs fit, too). These are much lighter, especially when you consider the extra weight of longer skewers. I always carry a 5mm allen when I ride, so the lack of a QR is no problem.



    Shimano XT M771 11-36 cassette
    Disclaimer: ComCycle USA

  27. #27
    mtbr member
    Reputation:
    Join Date
    Mar 2012
    Posts
    193
    awesome build so far... keep the pics coming

  28. #28
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    The project continues


    I scored this XTR E Type on eBay cheap. In order to use it you need to drill out the threads on the oval insert, which is not hard to do. And you do not need to use the mount plate. You must also provide your own mount bolts. I did not end up using the bolts shown here, you need to use button head style, or similar with heads that do not stick out so much, as the chain will hit them.


    XT 10 speed chain. Reads 277 grams


    So here is a partial build, now with a complete working drivetrain. The brakes are another matter, however, I need a new, longer hose for the rear if I want to move my brakes over from the old steed.


    A complete drivetrain means I can check rear tire clearance. This is the fit with Rolling Darryls, rear BFL, and an eThirteen snow crank, and a complete cassette. It really should have a little more clearance than this, I did a little truing to the casing/chain to get this much. Losing 1 cog, moving crank spacers, getting a different crank (The FSA/Fatback will give more clearance, I hear), etc. will do the job. But this is good news, the RD/BFL combo fits out back no problem.


    The chain looks a little deflected here, but that is due to rubber nubs on the sidewalls. The chain does not not rub.
    Disclaimer: ComCycle USA

  29. #29
    Geordie biker
    Reputation: saltyman's Avatar
    Join Date
    Nov 2009
    Posts
    1,376
    looking superb but im sure you will have issues in the top gears with tire rubbing.

    i thought i had room on large marge/BFL set up on my pugsley but they rubbed and slapped around when riding so i stuck nates back on.
    2014 milage so far - 2,485
    www.ukfatbikes.co.uk

  30. #30
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    Has anyone tried a Shadow+ rear derailleur? SRAM has something similar coming out. It keeps the chain from slapping around on the bottom. I have noticed if you keep the chain tighter you get less tire rub. I do not know if Shadow+ will help noticeably with top of the chain, though.
    Disclaimer: ComCycle USA

  31. #31
    A Surly Maverick
    Reputation: Dr Feelygood !'s Avatar
    Join Date
    Jun 2006
    Posts
    2,593
    Looking good DD

    Very much looking froward to the final reveal
    A Fatback'd Lefty for who life IS a Beach

  32. #32
    Dirt Huffer
    Reputation: AC/BC's Avatar
    Join Date
    Jun 2006
    Posts
    1,641
    Nice build! So what's the total weight now?

  33. #33
    Missouri sucks...
    Reputation:
    Join Date
    Jun 2009
    Posts
    2,306
    subscribed

  34. #34
    mtbr member
    Reputation: t0pcat's Avatar
    Join Date
    May 2012
    Posts
    527
    What year 650 GS is that in the background? I have an 09

  35. #35
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    Quote Originally Posted by t0pcat View Post
    What year 650 GS is that in the background? I have an 09
    '10. Fully Adventurized by the PO. I am tempted to put a bike (bicycle bike) rack on it.

    Good eye, BTW.
    Last edited by DirtDad; 05-10-2012 at 09:58 PM.
    Disclaimer: ComCycle USA

  36. #36
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518
    Quick update. I have been messing around with the dark side lately (moto). Then I decided to change a few parts on the Fatback. But I think I am happy with a final config now. I will take some time to weigh a few more bits and finish up soon.
    Disclaimer: ComCycle USA

  37. #37
    mtbr member
    Reputation: t0pcat's Avatar
    Join Date
    May 2012
    Posts
    527
    I think the idea of taking my bicycle with me on the bike would be cool but have yet to see a way to do it i would feel comforatable with.

  38. #38
    Compulsive Bike Builder
    Reputation: DirtDad's Avatar
    Join Date
    May 2002
    Posts
    1,518

    Final steps

    I made a few last minute changes to the build. Instead of reusing Marta brakes, I got a set of MT6's.



    This is the front only, cut hose, no rotor. I am using Shimano centerlock rotors, I weighed those separately already. Just to be complete, the rear is a little heavier due to longer hoses and an IS to PM adapter, so add this much for the rear



    And while I may be a weight weenie, I like lock on grips too much.



    So, time for a final weight:



    Compared to my beloved old steed:



    So I knocked a few pounds off, I made room for bigger tires/rims and I have a front tire tire that are easier to take on/off, I have a more corrosion resistant frame (important in ocean sand) and my frame does not have a hole corroded in the chainstay.

    So here is the completed bike, fresh from its maiden voyage to the beach and down to the pier and back (and a treatment of salt away):









    Some initial thoughts on the build and first ride. I am happy with the weight, and there is room for reduction. You could build with a full on X Country race build (XTR or XX, SLR saddle, that kind of thing) and smaller rims/tires (Marge lite, endomorphs, etc.).

    I have a BFL in the rear with one cog removed. One cog in the rear does not add much more clearance all the way up at the tire due to basic trig. A different crankset would make a bigger difference. I hate missing one gear in the middle of the range. I will probably swap tires (there is a Larry on the front right now) and see if I still get enough float. The drivetrain is a wide range 22/32/44 front and 11-36 in the rear. I like having the big ring, I use it on the pavement, and my beach riding around here usually involves connecting multiple beaches, trails, etc. with pavement. For long stretches I will even stop and add air to the tires. I have to have clipless for a good spin, it increases traction without spinning out, and I do not need snow boots for my riding.

    It rode admirably along the beach. The first ride involved basic wet sand, intermittent rock piles, etc. I was able to climb up the sand to the pedestrian trail in some really loose stuff. Steering is super stable. I like the nice wide bars. I need to fine tune my riding position. I will have to to a bigger ride with the bike fully dialed in to give it a proper review, but it looks good so far.
    Last edited by DirtDad; 05-18-2012 at 01:26 PM.
    Disclaimer: ComCycle USA

Similar Threads

  1. Replies: 47
    Last Post: 02-08-2012, 03:40 PM
  2. My closeout 2011 Sultan build
    By DFYFZX in forum Turner
    Replies: 18
    Last Post: 02-03-2012, 03:36 PM
  3. Replies: 9
    Last Post: 01-11-2012, 06:25 PM

Members who have read this thread: 0

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •