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passive/aggressive
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Discussion Starter · #1 · (Edited)
For years I rode the same old fuji. Purchased new in 1986. Upgrade and upgrade and upgrade to keep it running. Nothing new. Nothing fancy. Just a road bike and its rider. Then I graduated to a used Bianchi CX bike. Reparto Course. Italian tubing and lugged frame. Probably too small for me but it was cheap. 24lbs.

I commuted. I commuted more. I rode for fun. I did a century but ultimately it lacked that shimmering something that a good bike has. I got back on the Fuji. That too lacked it. I dreamed. I read buyers guides. Surf for bike porn RBR. Glossed over interbike coverage. NAHBS coverage. Press releases. Whatever.

I have a friend, owns a triathlon store. Carries litespeed.Titanium. The only metal bike I would get unless I could get a steel peggoretti (i can't). Litespeed comes for a race. End of their season and wanting to get rid of their demo bikes. My wife says do it. I jump like so many lemmings in a disney flick. Got a Siena, loved it a lot, rode it. Felt great in comparison to my dinosaurs but there was a lingering discomfort. I dismissed it as not being used to a 16lbs bike, the Ti, the racy geometry.

Take it up Mt Lemmon and on the way back down my speed pops over 34mph (i am gleefully watching the computer, euphoric to be riding a new road bike down a glossy smooth mountain descent, pushing it, watching the number build).

BOOM whooaaaaaaaaaaaaaaaaaaaaaaaaa whewwwwwwwww

Massive speed wobble. Deathly huge. Terrifying. I reel it in, keep rubber to pavement and skin on my body. Regaining my composure, slow down and check the obvious culprit: the QR's. The rear seems loose (was it? hindsight says it was loose. I am not sure now). I take it easy descending the rest of the way. Embarrassed. Timid.

I research the shimmy and determine that perhaps the super light wheels might be too light for me. I take the wheels from the bianchi. Solid, heavy, secure, confident strong enough for man. Give the uberlight wheels to my wife and set a date to try to do it again.

Just popping over 30mph gives me the willies. I just shut it down and coast back home defeated and dejected..

Swap out my handlebar. A stiffer CF one. Check the headset, the dish of the wheels, everything check out fine. "A plus ++1 fine would buy again - great seller" good. I head out again hoping, magically that it was solved by my tinkering.

Wasn't. Isn't.

I retire from fast rides. Screaming mountain descents.

Buddies: "Come ride Mt Lemmon with us"

me: "no, gotta do something"

them: "what?"

me: "something that isn't ride down Mt Lemmon"

them: "lame"

me: "I know. I suck (my bike sucks)".

My bike becomes a commuter. Heavy wheels, blinky lights, courier bag. Sad. Blasphemous. Ti. Come on.

Under power and out of the saddle the magnet on my wheel touches the sensor of my computer. Perplexed I began moving the sensor and magnet down the fork towards the dropout. When it gets near the spoke crossing it doesn't hit anymore. I check the wheels, retensioned them. Tick Tick Tick Tick. Hmm.

Fork. HP Designs OEM fork. Never liked it. Hard to mount a computer on. I call litespeed. They tell me take my frame to a local builder to check the alignment, could be out, demo bike and all.

I do it. Wasn't.

I borrow a fork. A new uncut steerer, 47mm offset close to the OEM, but not perfect.
Use the same headset, everything else, except a 4" tall stack of spacers. Looks really special. I throw the wheels in the jig and check their roundness and trueness and dish one more time. Good.

I head off to Mt. Lemmon on a very blustery windy day. Steel my nerves. Say goodbye to my wife, the boy. Thoughts of doom fly through my head:

it is too windy to do this today

what if you get blown sideways and it induces a speed wobble?

what if you die here on this stupid road, on this stupid bike


All 6 miles up my head fights my body. A valley where the winds were minimal and the road was straight. I stop. I brace myself, wipe the sweat off my brow, clean my sunglasses of sweat then turn my front wheel down the mountain.

Slowly I pick up speed, snicking off gears, softly pedaling, just sensing the bike. I don't look down, focus on the yellow line ahead. Ignore the hurling jagged rock face to my right, the precipitous drop off to my left. I just try to sense the bike, its demeanor:

Is it angry, responsive, defiant?

No wandering. No vagueness. None of that odd hunting feeling on bumps, no weird behaviors. Just singing along, the occasional buffeting of wind, small corrections but otherwise pretty normal. I am almost happy.

I look down at my computer...40mph. My stomach falls out of my body, down the seat tube and under the rear tire.

At 30 mph I would feel as I was about to be dashed against the rocks or plummet off the cliff. At 33mph my bike becomes a wild mustang, trying to buck me off, return to its pasture.

I freak out.

4" of exposed steerer waiting make my junk's acquaintance, speeds I have never reached, a building euphoria I haven't felt in so long. I jitter. I slow down. A lot. I glide along until I hit the esses and then slowly, guardedly I let off the brakes again.

Whoosh.

Bumpy corners: great. Straights: great. Under power: great. Braking: great. Ear to ear grin: great.

I am riding a new bike. Euphoric, excited, stoked and at the same time disappointed that something so banal as that fork, that damn fork, could have so affected my feelings towards my forever dream bike for such a long time. Titanium. The only metal bike I would get unless I could get a steel peggoretti (i can't).

I got home reborn. Stoked. I looked that the OEM fork. Squeezed it, twisted it, examined it, hated at it. No signs of its evil intentions. No indicators that it was so bad. Just a fork, a few grams of carbon and aluminum, inanimate but rendered in such as way as to almost kill my love for a bike. A Ti bike. My Ti bike.
 

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passive/aggressive
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Discussion Starter · #3 ·
Camilo said:
Hope you put the lightweight wheels back on! Great story,thanks.
yeah about that. I gave them to my wife which means they are no longer mine. I wish I had kept them but I will build up some light ones someday. Right now I am glad to have my bike back without all the crazy behaviors and I have a new Ritchey fork on the way with proper offset and less mustang craziness.
 

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Never experienced speed wobbles on a bicycle (and hope never to). I'd also be very timid to get back on that thing. Good thing you got it figured out.
 

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I had a similar experience with my dream bike. I have a 2005 Bianchi 928 that I LOVE!!! SRAM Red/Force mix with 50mm carbon tubulars. Earlier this year it develops what the next guy in line described as the "death wobbles" at about 34mph:cryin: . It started with the wheelset I rode all last year. Continued on my carbon tubulars.:idea: Similar diagnosis, the fork. My LBS had the exact fork and swapped it for mine. Next ride, first descent. Wobble, wobble, wobble. I was not pleased.:mad2: Second descent I figure screw it, I was always first or second down, not last by a few minutes. I let loose. No wobbles, 50 mph.:D Nor were there any on the third descent that day of any of the subsequent descents this season, all 45 mph+. I came to the conclusion that I was the cause of the wobbles. I think I lost my nerve one day for some reason that first day and tried too hard to keep control. :thumbsup:
 

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Adventure Seeker
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Good story. In the time I've spent here, my definition of a "dream bike" has changed considerably:
It's not the name,
It's not the frame material,
It's not the component group,
it's not the wheels,
it's not any combination of the above.
It is, a bike that gets ridden the most, and it's the one the owner looks forward to riding the most. Now if it looks good too, then that's just icing on the cake!
 

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Nice story- I have a Trek SL 5.9 and a Colnago Master X-Light and the Colnago is more stable on the descents. Maybe I will rethink about getting a ti bike in four years and go to a new steel bike..
 

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Great read - thanks for that. Glad you got your dream bike back. I routinely ride faster than 40mph. It would really suck not to be able to go over 30!
 

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passive/aggressive
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236 Posts
Discussion Starter · #12 ·
Peter P. said:
What brand carbon fork comes with a 47mm rake?

it is a quintana roo off a tribike I guess. I borrowed it from Trisports.com. Possibly a common triathlon fork offset.
 

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passive/aggressive
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Discussion Starter · #13 ·
jonathanb said:
Maybe Calfee knows a thing or two about forks and high speed wobble after all:
http://www.calfeedesign.com/forksymmetry.htm

JB
wow thanks for that link. That is exactly what i was experiencing and why I kept checking the dish on my wheels over and over again. Seemed like the bike turned one way a little better and the speed wobble began exciting a long right hander on to a straight.

I hope my ritchey fork I ordered is straight and symmetrical.
 

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Knives, Guns, and Booze
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Either your writing style is such that I was compelled to read the whole entry, or the paragraph returns were your saving grace.

So, I am now lost—did you actually figure out what was causing the speed wobbles and lack of confidence in high speeds on the bike?
 

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Glad to hear you nailed it and thanks for a good read! The elusive dreambike always comes with a new set of problems.. Thankfully I have taken mine up over 50mph without any trouble, though you really do notice everything that is flexing and moving at that speed.
 

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Fun read, thanks. You have a good writing style and it's apparent from reading it that you would be a fun person to ride with. Thanks again for the fun read.

Todd
 

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I do not like titles
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Great story I am glad you stuck with it to find out the problem.

I own a Litespeed bike with a HP Designs OEM fork. I did a group ride last night, and had my bike up over 37 mph with out the wobble that you describe. In case I ever do experience the wobble, I will want to know what works. I have never ordered a fork before and don't know how to determine offset. Can you share the specific model of fork you purchased? Also post a follow up once the Ritchey fork arrives and is ridden?

Thank you,

- Bruzer
 

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passive/aggressive
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236 Posts
Discussion Starter · #20 ·
Thanks for the kudos BTW. The HP design fork I thinks suffers from what was described in the calfee link, an asymmetry to the dropouts in relation to the steerer tube. Was it a manufacturing issue or just an issue with it having been a demo bike? Dunno. All I know is that slapping a triathlon bike fork with a crazy 47mm offset seemingly cured the issue.

I ordered the ritchey UD pro fork, matched to the OEM 45mm offset. All that is needed bruzer is to remove the old fork, take off your brakes, remove the existing headset race off the old fork and reinstall everything on the new fork. Install it on your bike, place your stem and all headset spacers you will use on the fork and mark it with a marker. Remove the fork, adjust the marking about 4mm towards the headset race and cut the fork steerer with a very fine tooth hacksaw (see manufacturer specs here). De burr the steer, reinstall, add the headset tension thing and tension it all up and tighten to manufacturers spec. If that seems too complicated I would always suggest letting a local shop do it for you, even if you don't buy the fork from them. Piece of mind and all.

should be getting a the fork friday and hopefully have it on by saturday to go and give it a try out. Better be it. I am tired of tinkering and want to just ride without a care.
 
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