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sirroada
09-03-2017, 09:24 PM
Hey guys,
I've asked about this issue before but there has been some changes and I wanted to add some details and ask further questions.
To make a long story short. New S-works (2015) purchased from LBS on clearance. Frame started peeling clear coat. Specialized replaced frame with new 2017 S-works frame putting all my parts on it (mechanical DA). I added Continental Grand Prix 4000 ii's once build was completed. Rode it on a century, wicked fast (21.5 mph average for 100 miles). Week following century bike ride I noticed a Nasty vibration in the front end. VERTICAL VIBRATION, NOT SIDE TO SIDE-THIS IS NOT WOBBLE. Tried everything myself and couldn't source the problem. The vibration was felt in the handle bars at speeds over 20 mph and got worse as I approached 30 mph. Bike goes back to Specialized. They find the front and rear wheels (Roval Rapide 40 clx) were both out of dish, out of true and the new Continental tires were bulging along the sidewalls. So, they installed new S-works tires, race tubes, trued and dished the wheels. I got it back and it is an entirely different bike. Smooth as glass, now up to about 34-35 mph where it used to be 20 mph. However, during high speed decents (35 mph+, I still get a vertical vibration in the front end. I can feel the front end going up and down and it is disconcerting, especially at 40 mph. I realize less than 1% of my riding is at this speed but on a 6 large plus grand tour race bike this sucker should inspire confidence while descending. Any ideas on what could be going on.
The LBS offered a deal on a new 2018 S-works, I'm tempted to take it but it would cost an additional 2500 bucks over the 5000 I paid for this one. Still not a bad deal on a 15 lb DI2 equipped rocket. But, I would like to save the money and figure this problem out. Any ideas?

bikinchris
09-03-2017, 09:43 PM
Have you tried swapping wheels? That would be first on my list.

fogrider
09-03-2017, 11:36 PM
+1 on swapping wheels. if you lift your bike and spin the wheels, can you feel that it's out of balance?

sdrides
09-04-2017, 04:55 AM
Lift the bike with one finger under the top tube. Have a friend spin each wheel up to speed individually and just see what you feel. Vertical wobble would suggest wheels out of round, not really out of dish or out of true. I think it would be hard to have the wheels TOO far out of dish or true on that frame anyway, as I imagine the tire clearances are pretty tight.

But a slight egg shape to the wheel can produce vertical wobble, especially if it's both wheels wobbling harmonically together. And I would imagine that your particular wheels, once out of round, might be difficult to get and hold round again.

You might also consider dropping by another shop for a second opinion. Your main guys sound like good people but it might be good to get a second, perhaps more objective, opinion.

oldpotatoe
09-04-2017, 06:38 AM
Have you tried swapping wheels? That would be first on my list.

Yup, sounds like the front wheel is either shaped like an egg or hugely out of balance.

Peter P.
09-04-2017, 06:53 AM
Another vote for a front wheel issue.

Since the rim is carbon I don't imagine there's much that can be done to radially true the wheel; you get what you get.

Install a borrowed front wheel and in fact, have a friend ride YOUR Roval wheel. See if the problem follows the wheel.

I'm guessing it's a balance issue. I don't suppose you have a computer magnet on it, do you? Perhaps remove it and see what happens.

dem
09-04-2017, 07:46 AM
If you're into marginal gains, you could balance your wheel and see if it helps. I did it for fun on one wheelset.. could tell no difference.

https://www.youtube.com/watch?v=dcgiUcbS64c

AngryScientist
09-04-2017, 08:10 AM
not only out of true/round/balance, but if a front wheel's bearings have even a little side to side play, that can come out as vibration in the front end under certain conditions.

additionally, before i went too much further nuts, i'd probably replace the headset bearings and be certain the preload is properly tight. thats a cheap experiment.

you might also want to experiment with tire pressure, particularly on the front wheel, a little more "cush" up front may just smooth out the issue.

sirroada
09-04-2017, 08:21 AM
Great thoughts all the way around. I've got a set of Hed Ardennes. I'm going to install the front one on this bike and ride it with the brake open (otherwise it won't fit), just up to speed and see what happens. An egg shaped wheel as one poster described is exactly how this vibration feels.

Ken Robb
09-04-2017, 11:12 AM
Great thoughts all the way around. I've got a set of Hed Ardennes. I'm going to install the front one on this bike and ride it with the brake open (otherwise it won't fit), just up to speed and see what happens. An egg shaped wheel as one poster described is exactly how this vibration feels.

If you ride it with the brake open it will still work right? That might be rather important on a high-speed descent. :D

sirroada
09-04-2017, 04:02 PM
If you ride it with the brake open it will still work right? That might be rather important on a high-speed descent. :D

Yep, rode it with the brake open. Had to deflate the front tire to get it into the brake, re inflated it and bombed some hills. Got it up to 42 mph, smooth as a whistle.

Ken Robb
09-04-2017, 05:24 PM
Yep, rode it with the brake open. Had to deflate the front tire to get it into the brake, re inflated it and bombed some hills. Got it up to 42 mph, smooth as a whistle.

Great news. Can you get the bouncy wheel replaced under warranty?

bikinchris
09-04-2017, 08:15 PM
Great news. Can you get the bouncy wheel replaced under warranty?

Better yet, trade it in for some other wheel. I like Rolf wheels.

sirroada
09-04-2017, 09:09 PM
Great news. Can you get the bouncy wheel replaced under warranty?

Gonna find out tomorrow. They are Roval Rapids CLX 40's. Super light and super fast but boy have they caused me some headaches.

oldpotatoe
09-05-2017, 06:54 AM
Gonna find out tomorrow. They are Roval Rapids CLX 40's. Super light and super fast but boy have they caused me some headaches.

Many, many good wheel sets out there that aren't 'Spec-Ed', insist on one of those...Campag/Fulcrum, shimano, even new mavics with new design rear hub...

uber
09-05-2017, 07:48 AM
I'm still stuck on the 21.5 average for 100 miles. Good on you!!!

soulspinner
09-05-2017, 09:05 AM
I'm still stuck on the 21.5 average for 100 miles. Good on you!!!

+1:hello: