# Wobbly 2007 Roubaix triple



## Davetone (Sep 10, 2007)

On the 10th of July I purchased the Specialized Roubaix Expert Triple after riding a Miele Lupa for 18 years and having a Trek 7500 commuter for 3. I log about 100 miles per week average. I'm 5'10 and at 172 pounds.
I have had my Lupa close to 50 mph on a few occasions and was more concerned with road conditions and traffic than the stability of the bike. Though heavier, it was stable even at that high speed.
The Roubaix, however, has been different. So far I have logged in 1395 miles in 3 months: I ride almost every day before work, riden 4 centuries and today finished the Tour de Tahoe.
I love everything about the bike except the serious wobble as I crest 41 - 42mph on a descent. Today the road was smooth as can be, but as I crept up on 40 I could feel it start to get squirelly and at 42 it would start this wobble/occilation that required me to clamp my knees on the top bar, and ease on he brakes, but put me in a awkward stance on the bike. I can't risk loosing control of this bike though I get passed too often.
I've had the wheels trued, I'm running Continental 4000 vectran at 120 psi.
Before I had hit 300 miles on it the head set started comming loose, and diring the Marin Century, the FSA cranks started to loosten up. I know there is a break in period, but I am concerned about this unstability about this fram design. I don't trust this bike.
Has anyone else had this problem on this model? 
Cheers and safe riding,
Dave


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## rbart4506 (Aug 4, 2004)

If you do a search there was a huge thread in the General Forum about a guy with that exact problem. I myself have an Expert and have no problems with shimmy on the bike and I routinely descend in the high 40mph range. These descents are short however, a mile or so max....


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## Davetone (Sep 10, 2007)

Thanks for the responce rbart. I'll check it out. It may just be the layup of a few frames during manufacture, but Have done a dozen or so decents over 40 and I get the same thing: the whole bike starts to shake and I fight to keep it stable.
On this last ride at Tahoe it did it again on a smooth highway, now I am just plain afraid of it. So, I'm bringing it back to the dealearship to see if they can prompt Specialized into looking at this.
Cheers,
Dave


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## RoubRider (Aug 1, 2007)

Wow, scary. I remember that other thread speaking of a similar case.

My 07 Expert Triple has not wobbled yet and I love those banzai descents, but I've only reached 46mph so far....(I'm too light).

Are you in full tuck on those descents? I imagine so at that speed. I have not had any instance yet to reduce my full confidence on max descents, smooth or not, 

Have them at least completely disassemble the headset and inspect the bearing alignment. *My headset and bottom bracket were both very slightly askew*, LBS fixed it right up.

ps. I exert light pressure on the bars when descending.

Tom


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## 2wheel-lee (Apr 23, 2007)

RoubRider said:


> Have them at least completely disassemble the headset and inspect the bearing alignment. *My headset and bottom bracket were both very slightly askew*, LBS fixed it right up.


Could you please explain your alignment problems on your headset and bottom bracket?


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## RoubRider (Aug 1, 2007)

2wheel-lee said:


> Could you please explain your alignment problems on your headset and bottom bracket?


On the stand, while slowly rotating the crank backwards I felt a slight reisistance at one point of the rotation. It was slight, but it was there, indicating possible bearing misalignment. The mechanic took everything apart, cleaned off every part, checked for nicks or nubs, examined the o-rings, re-seated the cartridge bearings and re-assembled. The rub is now gone, who knows exactly what was the exact cause, but the rub is gone and the bearings are smooooooth.

The headset has a slight popping sound when rotating the fork almost all the way around, they have checked the adjustment but I will have to take it in for a complete disassembly. The LBS guy I trust thinks its ok to ride until I can bring it in, and I agree. The headset feels very smooth, strong and perfectly adjusted.

Tom


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## Davetone (Sep 10, 2007)

Hi RoubRider & 2wheel-lee,
The headset was making this clunking sound while going over small rough spots on the road, and being new to the carbon frame I didn't recognize it at first, just knew something was amis. During the ride I stopped and bounced the front wheel a few times and figured it out, so as soon as I got back home I brought it down to the shop I purchased it from and mentioned the loose headset hoping and that would cure the wobble.
The guys at Mikes are really first class and got that dialed in quickly, and addressed a loose crankset. 
However this past Sunday I rode the Tour de Tahoe, which was just beautiful and the bike handled great, until I started the descent from Emerald bay and that wobble reared it's ugly head again as I started to hit 41. I was in full tuck, most of my weight on the pedals and knees in tight, chin nearly on the headset.
It was like a slow wobble/flex mid frame, mayby around 150-200 milliseconds,mixed with a small oscilation/vibration throughout around 60 milliseconds. I was holding on real tight and had to ease on the brakes to keep control of it as other riders blasted past. Rather frustrating, I must say.

I still have an odd click-click in the cranks when when the left is ascending at about the 10 o'clock position, mostly in the left side. The crank arms don't touch anything and neither does the chain... I though it could be my shoe/cleat, but I can feel it/hear it in both feet.

Beyond these issues, this is a fantastic bike. Right now it's being looked at by Mikes Bikes.
The only thing I can figure at this point, seeing as there has been some mention of this issue by another rider is that there may be some slight inconsistancy in the frame layup? Perhaps the alighnment of the rear wheel dropouts are slightly off?
I can't see why some Roubaix riders can top 46 and I get this problem as I hit 42-42.

I guess we'll see if the Specialized rep will take it for a descent? This company makes amazing stuff, that's why I picked Specialized!


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## mh3 (Mar 8, 2006)

Have them check your fork alignment as well. A slight misalignment or length discrepancy in the fork blades can sometimes be the culprit.


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## testtech (Aug 21, 2007)

*Possible frame resonance*

It is possible that the frame has a resonant frequency that corresponds to wheel RPM at the speed you notice the wobble. If this is the case the wobble will be reduced after you pass the resonant frequency, which means you go even faster. If there is a frame or other component resonance, it would not not necessarily take much wheel unbalance to provide excitation. For example, a speedometer magnet might provide enough unbalance. That said, go down the hill even faster and see if the wobble disappears or diminishes, then you might want a new frame.


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## Davetone (Sep 10, 2007)

This is an interesting point, and have heard this too from the techs at Mikes and other bike shops. I'm a professional musician, and have a project studio at home where I can record audio and examine the waveform. 
I put the bike op on a Blackburn trainer in the studio and decided to check 2 things. The click in the bottom bracket and the wheel wobble/hop/true. 

First I put the bike in it highes gear and spun it as fast as I could without the resistance wheel up against the road wheel. There was a noticable hop at about 35 mph, which might get worse as I get to 40 + MPH. I just couldn't spin it faster. 
Next I took a piece of magnet metal about the weight of the valve stem and affixed it opposite the stem, and spun it again. 
To my great surprise, the whell hop got worse. The whole frame shook from the vibration. In intervals of 1 spoke per test, I moved the counterweight to within 3 spokes of the valve stem before the wheel got quite anough to be noticable. There is no speedometer magnet on this wheel.
Observation: the wheel/tire/tube is grossly out of balance, and may change with any tire/tube replacement. This combination needs to be balanced to avoid high speed vibration.
I have no way to test the front wheel other that suspending it from fishing line through the axil hole perpendicular to the floor and observe which side droops, then counterbalancing until it's perfectly horizontal.
The clicks in the bottm bracket/cranks occur when the left crank arm is ascending to the 11 oclock position. 
I placed a Sennheiser 406 mike next to it and a contact transducer on the frame, then recorder myself pedaling to about 20 mph. After about 4 minutes there is a continuous click or double click i the exact same spot in the cranks. I have it recorded in the computer and you can hear it sonically, as well as see the spike in the wave form visually.
I am baffled and so are the techs at the shop...
I'm still having the wobble on the fast descents, too.
Specialized, please, help me out on this!!!


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## testtech (Aug 21, 2007)

Davetone said:


> This is an interesting point, and have heard this too from the techs at Mikes and other bike shops. I'm a professional musician, and have a project studio at home where I can record audio and examine the waveform.
> I put the bike op on a Blackburn trainer in the studio and decided to check 2 things. The click in the bottom bracket and the wheel wobble/hop/true.
> 
> First I put the bike in it highes gear and spun it as fast as I could without the resistance wheel up against the road wheel. There was a noticable hop at about 35 mph, which might get worse as I get to 40 + MPH. I just couldn't spin it faster.
> ...


Very resourceful. It appears that you have a wheel imbalance from some source. If you go down a hill with the proper balance solution in place, does your wobble disappear?

Unless the frame is cracked, I would not expect the bottom bracket click to contribute to the wobble. This certainly should not be imbalance issue (at the crank). I bet when you are going 40+ down a hill you are not pedaling. If you were to remove the cranks and potentially, open the bearings, you might see evidence of the once per RPM rub. However, I would start by simply replacing the external bearings. While the cranks are out, use a caliper to check the all bearing surfaces on the cranks are machined properly (no flat spots). Also make sure there is no play between the crank and shaft.


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## pr0230 (Jun 4, 2004)

*Speed whoble...*



Davetone said:


> On the 10th of July I purchased the Specialized Roubaix Expert Triple after riding a Miele Lupa for 18 years and having a Trek 7500 commuter for 3. I log about 100 miles per week average. I'm 5'10 and at 172 pounds.
> I have had my Lupa close to 50 mph on a few occasions and was more concerned with road conditions and traffic than the stability of the bike. Though heavier, it was stable even at that high speed.
> The Roubaix, however, has been different. So far I have logged in 1395 miles in 3 months: I ride almost every day before work, riden 4 centuries and today finished the Tour de Tahoe.
> I love everything about the bike except the serious wobble as I crest 41 - 42mph on a descent. Today the road was smooth as can be, but as I crept up on 40 I could feel it start to get squirelly and at 42 it would start this wobble/occilation that required me to clamp my knees on the top bar, and ease on he brakes, but put me in a awkward stance on the bike. I can't risk loosing control of this bike though I get passed too often.
> ...


Many of the new bikes today exibit speed whoble... I have read that Orbea Orca's have it, Cervelo Carbon soloists and my Airborne blackbird... The whoble is noticed especially on a downhill coast, with speeds approaching 30-40 mph... while the bike does the whoble , YOU are the cause... When you tense up, knowing that the whoble is coming, you START the bike to resonate... as in a startle... once you feel it the tendency is to HOLD tight and try to control the whoble... That is exactly the WRONG thing to do... 
You need to loosen YOUR grip and let the bike stabilize itself... use your knees to add stability to the frame, clamp them to the top tube... the biggest thing is to relax... and let the bike and you flow down the hill... When I approach a hill, I lower my elbows to relax.. Clamp my knees to the top tube, and relax my grip... If I feel myself start to tense, I take a deep breath to relax... 

The problem is your bike is lacking , lateral (sideways) stiffness in the Head tube... to check this, ride your old bike... and try to push the handlebars from side to side.... then ride your new bike ... your new bike should shimy from side to side easy... AND with less effort... 

I ride a Fuji Newest (all aluminum) and it is very stiff in in the head tube, My airborne blackbird was very unstable and I got rid of it... I also ride a BMC SL01... it is stiffer than the blackbird, but not as stiff as the Newest.... 

Hope this helps....

Joe Reganato 
Phila, Pa.


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