10 inch wide AP2V2s
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From: Olathe, KS
Originally Posted by ZDan,May 20 2010, 03:33 AM
Cool. But without spacers, I seriously doubt they'd fit (17x10" +84 offset). Perhaps what Jim was referring to.
Joined: Mar 2002
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From: Bellingham
Copied from original thread on Pacific Northwest Forum:
Regarding the cracked Volks:
These wheels were originally 7.5" wide fronts that I had widened to 10" for rear fitment. I had them widened by a repeatable shop that’s been doing this for 50 years. The way the wheels are widened is by cutting the rim into two pieces and inserting a hoop that is equal to the desired width increase plus any kerf loss. The hoop is tig welded from both sides. Between each weld pass (4 total), the wheel is allowed to cool. At no point does the face of the wheel get any hotter than it would during a track day. After widening, I replaced the tires with R888's which have less grip than the V710's that were on the wheels previously. The wheels displayed no visible evidence of damage after the first track day but only lasted 2 sessions on the second track day.
My current theory is that the failure was due to a reduction in hoop strength/stiffness caused by widening (lower strength heat affected zone, lower strength hoop insert, moving the rim flange (which adds rigidity due to geometry) 2.5" further away, etc. With the barrel/rim having lower strength and stiffness, I believe more load was directly transmitted to the individual spokes and a 14 lb 17 X 10 wheel can take only so much load. These wheels never hit anything and never went off track and are only used for track and auto-x events. One wheel was hanging on by a thread (I'm very lucky it stayed together long enough to get to the pits about 5 turns after the initial catastrophic failure at a very ginger pace). The other rear wheel has one spoke cracked all the way through. Given that they failed at nearly the exact same time tells me that the one wheel wasn't just some random failure.
Given the fact that these wheels were highly modified, I don't plan to even discuss this issue with Volk. I wouldn't expect them to warranty a wheel after someone modifies it. I still have full confidence in the other two un-modified wheels (17 X 9's).
Regarding the cracked Volks:
These wheels were originally 7.5" wide fronts that I had widened to 10" for rear fitment. I had them widened by a repeatable shop that’s been doing this for 50 years. The way the wheels are widened is by cutting the rim into two pieces and inserting a hoop that is equal to the desired width increase plus any kerf loss. The hoop is tig welded from both sides. Between each weld pass (4 total), the wheel is allowed to cool. At no point does the face of the wheel get any hotter than it would during a track day. After widening, I replaced the tires with R888's which have less grip than the V710's that were on the wheels previously. The wheels displayed no visible evidence of damage after the first track day but only lasted 2 sessions on the second track day.
My current theory is that the failure was due to a reduction in hoop strength/stiffness caused by widening (lower strength heat affected zone, lower strength hoop insert, moving the rim flange (which adds rigidity due to geometry) 2.5" further away, etc. With the barrel/rim having lower strength and stiffness, I believe more load was directly transmitted to the individual spokes and a 14 lb 17 X 10 wheel can take only so much load. These wheels never hit anything and never went off track and are only used for track and auto-x events. One wheel was hanging on by a thread (I'm very lucky it stayed together long enough to get to the pits about 5 turns after the initial catastrophic failure at a very ginger pace). The other rear wheel has one spoke cracked all the way through. Given that they failed at nearly the exact same time tells me that the one wheel wasn't just some random failure.
Given the fact that these wheels were highly modified, I don't plan to even discuss this issue with Volk. I wouldn't expect them to warranty a wheel after someone modifies it. I still have full confidence in the other two un-modified wheels (17 X 9's).
Joined: Dec 2004
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From: Land of Cincinnati Chili
Originally Posted by ans2k,May 20 2010, 03:59 PM
what does the widening have anything to do with the spokes? do brand name companies actually add strength to the spokes as the rim gets wider? but damn that is crazy!
L
Now imagine that the top of the letter L is the top of the spoke where it is attached to the center hub of the wheel. The vertical leg of the L is the spoke. The horizontal leg of the L is a simplified version of the outer part of the wheel around which the tire mounts (yes we all know it is really curved but it doesn't matter for this discussion).
Imagine that the L is hanging in space suspended by the very top of the vertical leg. When you apply force to lift or lower the horizontal leg of the L or push the lower leg of the L into and out of your computer screen, you simulate the forces exerted on the wheel spoke while driving, cornering, hitting bumps, etc.
Now..... lengthen the horizontal leg of the L (including it's wider tire patch around it) and do the same thing. SEE THE PROBLEM? You dramatically increase the forces on the spoke because you have lengthened the lever arm. The wheel spoke is designed to withstand given forces and you are changing the design parameters for the worse.
Does that explanation help?
