In case you haven't figured this out, this is the S2000 driver in question...
Terry can you measure one of your 17x10s in this location? I'm looking at some more recent pictures in my s2ki.com thread and I think Forgestar changed the casting--added a lot more material! Do you have a loose wheel you can weigh? Mine were 17.75lbs.
I checked and yes, our 17x10 F14 has thicker spokes than this 3+ year old F14 17" version. I just talked to Vincent at Forgestar and here's the scoop:
The 17" F14 was designed in early 2013 and released at SEMA that year. They designed these to a 1400 pound rating, with a slightly different shape to the spoke that didn't match their 18" F14. Seeing that most 17" wheel buyers would only run 17" at both ends, it would have a lighter weight and look fine.
- Original F14 in 17" was rated at 1400 pounds (plenty strong for a 2600 pound S2000)
- The updated design for the 14" F14 is rated to 1520 pounds (due to aesthetics changes)
- The F14 in 18" is rated to 1520 pounds
- The F14 in 19/20" is rated to 1600 pounds (smaller sidewalls dictate this move)
Turns out some C5 Corvette guys ran the staggered Forgestar 17" front / 18" rear (just like the factory C5 wheels), and they wanted the 17" F14 spoke shape to match
visually with the 18" F14 version. So Forgestar changed the mold for the raw 17" F14 wheel to match the spoke of the 18" F14, for aesthetics, then had the new wheel tested - which came to a higher 1520 pound rating (it also gained a small amount of weight). This change happened in mid-2014 and they ran through most of the lighter 1400 rated wheels sometime in 2015. All of their current F14 17x10" blanks are the 1520 rated wheels, like we the ones have on our car.
So this wasn't done as some "fundamental design change", or due to some failures, it was done strictly to match the
appearance of the 18" F14 spokes. Yes, the new 17" F14 is stronger and matches the 18" F14 rating, but its not a huge difference in weight between the two designs (0.8 pounds, according to Forgestar). There is still more weight difference in pad depth changes from this S2000 set to say... our E46 set. Pad depth still does not dictate strength, either.
Picking wheel load ratings is kind of a
no win situation for wheel designers. Pick a lower rating and you get a wheel with less weight, which racers like, but there's going to be some abusive user who will break one
sooner. Then complaints come the FIRST time somebody wrecks a wheel. Pick a
higher load rating and you will end up with a stronger but heavier wheel, and people will complain about weight.
Lose-Lose.
We went through this with D-Force between 2006-2011. One of the wheels we helped them spec in 2007 for sizing was an 18x10" wheel for BMWs, which were built around a 1400 pound rating. When we went back to them in early 2011 to make a test set for our 3600 pound 2011 Mustang in the same size and offset, they did a "Drill and fill" on a BMW 18x10" wheel set to convert them from the BMW 5x120mm to the Ford 5x114.3mm pattern. These were still made for the lower 1400 pound rating but we beat the snot out of these wheels for 3 years on our car with track, autocross and street abuse. No cracks.
When we test fit them and liked it, we put in a 100 piece order to have this 18x10" wheel made for the S197 Mustang (nobody else at the time made an 18x10" wheel for the S197 that fit under the fenders at both ends). Tom at D-Force was concerned about the heavier Mustangs and we both agreed to add ~1.2 pounds to the wheel to move it up to a 1560 pound rating. The added thickness went into the spokes, just as the F14 change did. We did this to head off the "lowest common denominator" drivers who abused them, and so far we haven't regretted that. Yes, it made the wheel heavier, and we saw complaints when the production S197 18x10" wheel was heavier than the prototype. Lose-Lose...
There haven't been a rash of D-Force wheels failing but we still encourage our customers to clean and check their track wheels regularly - no matter the wheel brand. Some folks actually listen to us (see above). We did have one customer who broke the lighter spec BMW 18x10 D-Force wheels, but he broke everything on that car - because he constantly hit curbs, had big "offs", and drove 11/10ths everywhere. He was running in competition, and he "consumed" more consumables than most. We encouraged him to go to a heavier wheel and he has had no problems since. One of the rare issues with 18" D-Force failures - but again, it can be traced back to the user.
So while I have learned that there was indeed a change in wheel spec on the 17" F14, it wasn't drastic nor deemed necessary due to a string of failures. This is the
first 17" F14 failure I've heard about - but it just got a LOT of internet coverage. Freagin car "news" sites reposted this guy's video, "helpful" Facebook users, forums, and on and on. I admit, it was a slickly made video and his side shot camera angle was perfect, showing the barrel come off. It would be hard
not to share that... but I wish he would have made a phone call before he did. I honestly feel he
threw Forgestar under the bus for something he directly contributed to more than any other factor.
Do I pick on the end user here a bit? Sure, I fully admit to discrediting this video, on purpose. Why?
Because it needed to be. First of all, he ran these wheels for much longer than he led folks to believe. Over 2 years, approaching 3. Secondly, he
HIT EVERY CURB ON TRACK, pretty damned hard, in the short video where his one wheel failed. Third, he had a
100+ mph "off" just a handful of weeks earlier at another track event, which he shows on his YouTube channel. We can also see in all of his track videos where his car's
suspension is bottoming out HARD - both from curb hits and regular track bumps. The ride height is too low and/or the spring rates are too soft. This car also has aero at both ends, which adds more suspension compression at higher speeds, taking away suspension travel. Turns out he blew out some KW coilovers, too. All of these things point to more of a
user issue not a wheel design problem. Even in the video he admits he should have
inspected his wheels more frequently - because the cracks were OLD and had taken some time to completely fail.
The way he posted the video was not .... well, not how most adults would handle a potential product problem. Instead of spending the time to crop together his multi-angle video and pictures and screaming "THAT'S THE PROBLEM WITH FORGESTARS!!" as his wheel came apart (2.5 years after he bought them?!), he could have picked up a phone and called his wheel dealer or Forgestar directly. Sent them the video, where they could have pointed out his driving issues (curbs, offs) and setup issues (ride height too low) and age of the cracks (old) that contributed to the fatigue failure of all 4 wheels.
I'd be
embarrassed if I had put this much effort into a video that pointed to
me as the main problem. Because this video does just that, if you can look past the pretty camera angles and screaming kid behind the wheel. This failure didn't happen quickly - it took YEARS of this driver beating on these wheels to fail them. But what's most telling is that all 4 wheels had the same fatigue cracks, almost as if he had a high impact incident
very recently that led to massive spoke failure on all 4 wheels. Again, the 100 mph "off" he had in his previous video was pretty rough, and I suspect that incident caused all of the cracks. It took another track weekend to fail a wheel, so again, this wasn't a spontaneous failure.
I'm really tired about writing about this ONE incident. As we have pointed out numerous times, we have NOT seen a pattern of spontaneous wheel failures with Forgestars, neither with our own cars or the hundreds of customers we've sold them to. This is the first documented fatigue failure we have seen with this brand. And trust me, I've only been tagged about 20 times on this ONE wheel failure, I'd know.
But like we've seen with ALL wheel brands, it was only a matter of time before someone failed a Forgestar. I can find similar fatigue failures for every brand of wheel EVER made. Endurance fatigue affects every wheel make, model and style. The other culprit - total lack of wheel inspections and massive driver abuse - also claim every wheel brand out there. As Forgestars gain in popularity they get into the hands of more and more users. The lower price point pushed them into the hands of.... well... kids, who often react like this guy did (overreacted). Straight to the internet, looking for attention. Don't bother to call the manufacturer - who was more than willing to look at the wheels, and even gave this guy ALL of his money back.
So let's just give it a freagin' rest. You can
hate on me for standing up for a product I believe in, for a product I have tested and beat on and have real experiences with. Call me the the "bad guy" since I called out the driver for his
massive abuses that led to this failure. Go for it, I've got thick skin, hehe.
Its still the truth. These wheels just aren't the problem here. Let's cut out the new troll accounts, coming in here stinking up the place like a bunch of children, throwing an internet tantrum. The S2000 driver
knows he has some setup problems, knows he hits a lot of curbs, knows he has had some big offs, and knows he has a string of other "parts failures". He seems to be owning up to this,
at least a little but, but still wants to get as much fame out of this as he can. Whatever, he's young, and some day he might realize this wasn't the best way to handle this.
Cheers,