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  1. #1
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    Bike check: Skippy's PBJ.

    A little over a year ago I convinced Devin Lenz to build a 7" travel 'park bike'. Almost immediately after taking delivery I pointed myself north and rode it for a few days in Whistler. The experience of riding in Whistler is not likely to be duplicated in many other places on the planet--so big, so fast, so steep, so much slippery rock, often so little traction. And the trails--so much variety, all of it challenging. It is the most demanding riding I've ever done when you factor in bike, body, and mind. Body and mind get to rest and recover *a little* every night, but the bike just keeps getting pounded relentlessly.

    So it was with mild elation that I finished last year's trip unscathed and reported back to Devin on how the proto park bike performed. Devin took that feedback and mixed in a little mojo to create some more refined prototypes. These were disseminated last fall and ridden heavily from Denver to Moab and lots of mountainous places in between. Over the winter Devin took that feedback and made some final tweaks to the geometry before releasing them to the public this spring. I bought one of the first production bikes to have as a 'shop demo' of sorts.


    Which has worked out pretty well for Skippy. He piloted it a few times at Trestle Bike Park this summer--enough 'to get a feel for the way it flies', which seemed to be his main concern. He's ridden rental 26" DH bikes on all of his previous trips to Whizzler, so he has some basis for comparison. When we started hammering out the details of this year's fall Whizzler trip, he expressed (significant!) interest in an extended demo session on the PBJ. I didn't see a good reason to leave this bike at home when A. We had room in the truck and 2. It was/is tailor made for the riding we'd be doing. So we brought it, and he's been riding it.


    And I dare say he has been ripping on it. I'll have some video after the trip is over that shows (far better than my words ever could) how big, how fast, and how far he's been pushing this bike. For now, a few pics to answer the nitty gritties about the bike itself, accompanied (below) by some words from the horse's mouth.

    The frame is a size medium. The fork is a White Brothers Groove 200. That's 8" of fork travel to match the 7 inches out back.


    About the only 'personal tweak' he's made to the bike is to rotate the bars into this position:


    They look uncomfortable as all get out *to me*, but I don't have to ride it and they sure aren't slowing him down any.

    Front hub is a 36h DT 440 in 20mm thru. Rim is a Sun MTX 33. Spokes are DT Competition butted, laced 3x. Nips are DT aluminum.


    Saint 170mm cranks, 32t ring, MRP G2 guide, and Mallets.


    Vivid coil shock with 550# spring and medium drop-stop bumper.


    One of the more unique features of this bike is the rear hub. It is a very rare iteration of the DT Swiss 440 FR. This one is 150mm spaced, but uses a single-speed freehub body, so you get (duh--LOOK at it!) MASSIVE flange spacing, which gives you a ridiculously stiff, strong, and durable wheel. This hub is actually only available in 32h, and I've laced it to a Salsa Semi rim (that's a light XC rim, folks) using DT Comps and DT alloy nips.


    I've seen what Skippy has done to this wheel the past few days (think landing sideways at 25mph about 150 times per day...) and I've checked it over to find it still perfectly round and true. From that I can only conclude that it is the most durable wheel necessary for this sort of thing. And even though the rim is but a scant ~550g, this is probably the most durable wheel I've *ever* built. Really. Sure, I could build it heavier, and for a 350# rider I just might. But for Skippy it's plenty.


    The SS freehub body means you're somewhat limited with gearing selection. I wanted to keep this setup simple and functional and duplicable (in case of crash or failure) so I just mined 5 cogs from a stock SRAM road cassette. That's a 12-27 spread on there--plenty of range for park riding and even *some* self-shuttling. Rear mech is a Saint short cage, moved by a SRAM Attack twist shifter.


    Brakes are Avid Code, 8" up front and 7" out back. The rear brake has had a disconcerting resonance from the get-go. Fine-tuning the relationship of the caliper to the rotor has made no difference. Swapping sintered pads for organic made no difference. Replacing rotors *and* pads at the same time has made no difference. Plenty of power, plenty of modulation, just a really, really annoying noise that can be felt *and* heard when riding.


    Rock Shox 12 x 150mm Maxle ties the rear end together. These seem to get overlooked or glossed over for some reason, but I think they are one of the brighter bike inventions of the past few years. Simple, durable, even elegant, they add stiffness where maybe you didn't even realize it was lacking.


    Post is a cheapie Truvativ cut pretty short. Saddle is a big honkin' Bontrager Earl because bigger is better for park riding.


    Cane Creek 110 HS, Funn direct mount stem, Sunline V1 semi-flat (not-so-rise?) bars, inverted to keep the front end height where he wanted it. Full/unbroken housing run from the shifter to the rear der. Clean.


    Shod with WTB Dissents in 29 x 2.5", and running Bontrager 29 x 2.1" XC tubes at ~25ish PSI.


    Great--that's the machine, but what does the rider think of it?

    Here are some of his random thoughts:
    Fork? "Buttery smooth on small stuff, bottomless on big hits. Normally after a few days in the park my hands are killing me. Not this year. Only complaint is the thru-axle install/removal seems not very well thought out."
    Rear shock? "Invisible--just does it's job without noise or complaint. Very nice."
    Tires? "Great in the slop, great in the dry, no complaints."
    Brakes? "Noisy. Power is good, modulation is good, just too noisy."
    Gearing? "Perfect for park riding. On occasion I wish I had a few easier climbing gears so that I could self-shuttle. But then I'd have to pedal a 40lb slammed-post bike uphill!"
    Wheel flex? "None. Zero."
    Chain guide--any noise, slap, derailments? "None--seems to be a zero-maintenance system. I like that I haven't thought once about it 'til you just asked me."
    Given a clean slate, what would you change? "Brakes, to something that doesn't scream at me, and the fork thru-axle to something quick and easy like a Maxle."
    Any interest in going back to a 26" DH bike? "My only interest would be to compare them in the air on big booters, tables, gaps. But I don't see going back to 26".
    Care to comment on 26" vs. 29" for park-sized braking bumps and chop? "No comparison, 29" is worlds smoother."

    Great to get such unfettered feedback.

    And now, it's getting to be that time--lifts open in 45 minutes!

    Cheers,

    MC

  2. #2
    It's carbon dontcha know.
    Reputation: 6thElement's Avatar
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    Great write up, nice looking sled. What size Vivid is it?

    I had way too much trouble with Codes, after the 2nd RMA I just sold them and went for Hope V2's on the big bike.

  3. #3
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    Reputation: Enel's Avatar
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    Very nice review.
    Quote Originally Posted by buddhak
    And I thought I had a bike obsession. You are at once tragic and awesome.

  4. #4
    Naturally Organic
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    Cool-blue Rhythm Nice!

    Thanks for sharing.
    The story & pics are awesome!
    Looking forward to the video!

  5. #5
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    Very nice. If I had some parks within 200 miles of where I live and was in the market for a park bike.... this one would be high on my list.

    Do you have an idea on the weight (without the mud of course)?

  6. #6
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    Reputation: mikesee's Avatar
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    Quote Originally Posted by KRob
    Very nice. If I had some parks within 200 miles of where I live and was in the market for a park bike.... this one would be high on my list.

    Do you have an idea on the weight (without the mud of course)?
    I think both my personal bike and the demo come in right around 39. Could be much worse.

    I don't often take mine on XC epics, but I have, and will continue to in the future. Sometimes it's just the right tool for the job, especially when you mix "XC" and 'epic' with 'Moab'...

    Cheers,

    MC

  7. #7
    Fat & Single
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    That is one sweet looking bike
    Ti O'Beast
    Indy Fab
    One9
    Dirty Disco CX

  8. #8
    This place needs an enema
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    Quote Originally Posted by 6thElement
    Great write up, nice looking sled. What size Vivid is it?

    I had way too much trouble with Codes, after the 2nd RMA I just sold them and went for Hope V2's on the big bike.
    The Vivid is a 200 x 57.

    The Code's on this bike are likely to get warrantied for something Elixir or X.O-ish.

    MC

  9. #9
    It's carbon dontcha know.
    Reputation: 6thElement's Avatar
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    The Elixir CR Mags I have on another bike have been great, I think they're equivilent to the new X.0's.

  10. #10
    GUIDANCE COUNSELOR
    Reputation: NoahColorado's Avatar
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    Very cool indeed. Thanks!
    NOAH SEARS
    MRP
    TECH QUESTIONS HERE: INFO@MRPBIKE.COM

  11. #11
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    ow that rear hub is nice!!!! I wonder if they will be available to the general public.

  12. #12
    Bite Me.
    Reputation: cutthroat's Avatar
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    Apparently you and Skippy didn't get the memo. 29ers just don't work for that type of riding.

    Nice looking bike - I hate to think of the bodily injuries I could sustain on that thing. The Behemoth is already making me try things I shouldn't. That rig would kill me.
    When I see an adult on a bicycle, I do not despair for the future of the human race. ~H.G. Wells

  13. #13
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    Quote Originally Posted by mikesee
    I think both my personal bike and the demo come in right around 39. Could be much worse.

    I don't often take mine on XC epics, but I have, and will continue to in the future. Sometimes it's just the right tool for the job, especially when you mix "XC" and 'epic' with 'Moab'...

    Cheers,

    MC
    That's not bad. With dual ply tires and heavier tubes my Knolly clocks in right around there too and it certainly is worth hauling on all-day epics if there's significant chunk and features to play on. Still you'd have to admit that, geometry and seat post considered, the PBJ is more park bike/DH rig than AM cruiser..... like 90/10. There's obviously more to an AM rig than just weight.

    Having said all that..... I've seen the video and ridden this bike and know that it pedals really well.

  14. #14
    This place needs an enema
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    Quote Originally Posted by KRob
    That's not bad. With dual ply tires and heavier tubes my Knolly clocks in right around there too and it certainly is worth hauling on all-day epics if there's significant chunk and features to play on. Still you'd have to admit that, geometry and seat post considered, the PBJ is more park bike/DH rig than AM cruiser..... like 90/10. There's obviously more to an AM rig than just weight.

    Having said all that..... I've seen the video and ridden this bike and know that it pedals really well.
    To me, the only bummer about pedaling this bike all day is the short seat tube. Just a bit too short to run a dropper post, and yeah, I've gotten spoiled enough that I don't like to stop and drop the post for tech stuff. Maybe I should grow 3" longer legs?

    MC

  15. #15
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    Brake noise

    Did you consider that the frames brake tab flex may be a factor contributing to the brake noise?

  16. #16
    Geritol Power
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    Quote Originally Posted by BCKDXR
    Did you consider that the frames brake tab flex may be a factor contributing to the brake noise?
    That would be my guess too. Any brake with a big rotor on some frames just make noise. Let us know if you find a solution to the noise Mike

  17. #17
    HTFU and Ride
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    gnarcore
    Winter is coming.

  18. #18
    This place needs an enema
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    Fade to Black, Skippy's eye view.

    So there's this new trail at Whizzler called Fade to Black. New realm for the WBP with wood features like a road gap, step up to wood platform to step down, etc...

    Here's Skippy's helmet cam view of it:


    The first road gap is psick--roughly 10' of drop into a *tight* right hand berm. The first time I saw it I happily volunteered to be photogeek at that spot while he dropped it/took the clip above.

    The step up and step down are pretty committing too, though if you've cleared the road gap and made it to that point they're baby food, relatively speaking.

    One more day in the park, tomorrow. Hoping for clear-ish skies so that I can tick that one off my top-to-bottom-clean list.

    MC

  19. #19
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    Quote Originally Posted by Duzitall
    That would be my guess too. Any brake with a big rotor on some frames just make noise. Let us know if you find a solution to the noise Mike
    Elixir's don't make noise on these frames. Nor do Stroker Trails, Grams, or Ace's. Only the Codes.

    Same Code howls on my LunchBox and Behemoth. It's something in the brake/pad/rotor combo.

    MC

  20. #20
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    Quote Originally Posted by DiDaDunlop
    ow that rear hub is nice!!!! I wonder if they will be available to the general public.
    They already are, though they were/are made in such limited quantities that it might take you awhile to source one.

    MC

  21. #21
    JB
    Reputation: Nevada 29er's Avatar
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    Quote Originally Posted by BCKDXR
    Did you consider that the frames brake tab flex may be a factor contributing to the brake noise?
    That's an easy fix, its called Shimano!

  22. #22
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    Brake idea

    I noticed on the front bolt of the rear caliper, it is missing the alignment washers on the bolt head side. I wonder if that is on purpose or if that creates some problem with caliper alignment with the rotor that contributes to the noise. I can't imagine that the caliper has been on and off and so many other things done to it that that is the only problem, but...

  23. #23
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    Quote Originally Posted by scout6
    I noticed on the front bolt of the rear caliper, it is missing the alignment washers on the bolt head side. I wonder if that is on purpose or if that creates some problem with caliper alignment with the rotor that contributes to the noise. I can't imagine that the caliper has been on and off and so many other things done to it that that is the only problem, but...
    Very keen eye to notice that one. It's indeed missing.

  24. #24
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    Quote Originally Posted by scout6
    I noticed on the front bolt of the rear caliper, it is missing the alignment washers on the bolt head side. I wonder if that is on purpose or if that creates some problem with caliper alignment with the rotor that contributes to the noise. I can't imagine that the caliper has been on and off and so many other things done to it that that is the only problem, but...
    The resonance was there with the washers set as 'stock', but the caliper was sitting several mm's too high on the rotor. So I removed the washers as a means for getting the proper amount of pad in contact with the rotor. No difference in noise either way.

  25. #25
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    Quote Originally Posted by mikesee
    Just a bit too short to run a dropper post...

    MC
    I've got a 2" to 2 1/2" drop Maverick Speedball you can have if that will help. It's supposed to drop 3 inches but there's a half inch + of 'settling' at the top of the stroke that kinda squelches its effectiveness.



    It also wags its nose back and forth 10-15 degrees to help minimize butt chaffing as you pedal.

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