Flexing - is it my rims, or the AR2?
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Flexing - is it my rims, or the AR2?
Hi Folks! I need some help.
I just picked up a new 2010 AR2 that was collecting dust at my LBS. Just coming off a 2009 Giant Devy Adv 2 which was my first bike. I found the AR2 to be FAST and I'm loving the high end components and frame! I'm quickly finding out that the top end gear requires happy and expensive mates all surrounding it.
On to my question..
So the AR2 came with what I have since found out at Zipp FP40/303's. They are nice rims, however I have a set of Easton EC70 SL's (the discontinued ones) and the overall quality including graphics seems nicer. The Zipp's were very quick and light when I rode it last week.
So I threw on the EC70 SL's and went out on a group ride with some nice new red Conti 4000's. Right out of the driveway, while standing up, I felt a pronounced VVVVWWWOOOOOOOONK. It kinda freaked me out.
After troubleshooting for a few minutes, I found it was the rim hitting the brake pad. The Zipp's had about 1-2mm spacing from the factory, so I left it there with the EC's.
I fully unlocked the brake clamp, rode some more, and was able to reproduce the noise while sprinting at about 70%. This is kinda freaking me out. I have 1/4+ inch gap and the rim is still hitting.
Troubleshooting, I swapped back the Zipps, locked down the brake, and no rubbing under full sprinting.
I swapped the skewers thinking that might be it, no dice. The Eastons never did this flexing thing on the Giant.
I can't figure out what the issue is here. Is it possible that the Giant was so mushy that the frame flex ate the rubbing, and that the AR2 is much stiffer exaggerating the wheel flex?
Is the Ar2 flexing and causing this (if so, it's going back tomorrow)?
Are Eastons notorious for this? Mine are only 4 months old and I would be incredibly pissed for the pricepoint of a high end product if they are this poor.
Thanks guys!
I just picked up a new 2010 AR2 that was collecting dust at my LBS. Just coming off a 2009 Giant Devy Adv 2 which was my first bike. I found the AR2 to be FAST and I'm loving the high end components and frame! I'm quickly finding out that the top end gear requires happy and expensive mates all surrounding it.
On to my question..
So the AR2 came with what I have since found out at Zipp FP40/303's. They are nice rims, however I have a set of Easton EC70 SL's (the discontinued ones) and the overall quality including graphics seems nicer. The Zipp's were very quick and light when I rode it last week.
So I threw on the EC70 SL's and went out on a group ride with some nice new red Conti 4000's. Right out of the driveway, while standing up, I felt a pronounced VVVVWWWOOOOOOOONK. It kinda freaked me out.
After troubleshooting for a few minutes, I found it was the rim hitting the brake pad. The Zipp's had about 1-2mm spacing from the factory, so I left it there with the EC's.
I fully unlocked the brake clamp, rode some more, and was able to reproduce the noise while sprinting at about 70%. This is kinda freaking me out. I have 1/4+ inch gap and the rim is still hitting.
Troubleshooting, I swapped back the Zipps, locked down the brake, and no rubbing under full sprinting.
I swapped the skewers thinking that might be it, no dice. The Eastons never did this flexing thing on the Giant.
I can't figure out what the issue is here. Is it possible that the Giant was so mushy that the frame flex ate the rubbing, and that the AR2 is much stiffer exaggerating the wheel flex?
Is the Ar2 flexing and causing this (if so, it's going back tomorrow)?
Are Eastons notorious for this? Mine are only 4 months old and I would be incredibly pissed for the pricepoint of a high end product if they are this poor.
Thanks guys!
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Fwiw, I have an '10 AR1, I'm out of the saddle a lot, and I haven't gas that problem. I believe the frames are the same.
But I'll be following this thread in case you get to the bottom of this
But I'll be following this thread in case you get to the bottom of this
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Thanks IN, I'm 99% sure it's the rims and doubt it's the frame. I hope someone out there tells me that the Easton rims overflex, and that's what's causing it.
Best-- MD
Best-- MD
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Is it only the rear wheel rubbing the brake pads? If so, you could still compare front wheel lateral flex between the 2 set of wheels by spacing the front brake pads *real* close to the rim.
Another simple comparison: Use the quick release on the brakes. Try pulling the rim sideways against the fork or the seatstays, levering against your thumbs. You will feel and see any larger variation in lateral stiffness immediately. (And will probably be surprised how little lateral stiffness a wheel has)
Another simple comparison: Use the quick release on the brakes. Try pulling the rim sideways against the fork or the seatstays, levering against your thumbs. You will feel and see any larger variation in lateral stiffness immediately. (And will probably be surprised how little lateral stiffness a wheel has)