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Great article!

What price are the new wheels going to go for and is he going to offer the believers that got refunds the opertunity of getting the old price they ponied up in the begining?

So what these rings gonna cost?

For prospective buyers, I think that if there is anything to be learned from the last year, it can be summed up in three words: Wait and see.

This is progress, but not completion. Durrani has to get the front and both rear wheels (5 1/2" and 6") to pass all if those tests, which will take several weeks if everything goes well. As we have seen, sometimes it takes longer...

Once that happens, then I think that issues of pricing and delivery will be widely disseminated.

Good luck to him. Yep I will certainly wait and see. Though it would be good to see hard work and risk taking pay off even in the new age of socialism.

Interesting follow on article. I'm really looking forward to seeing how well the mold-fill analysis worked for the longer flow path of the rear. It looks like there might be some blush issues with the front, so it would follow that the rear might have more issues with both blushing and flow lines. Any info on what the new secondary finishing process will be?

Also would like to hear more detail about the threaded hub design, how it is preloaded and retained. And more interestingly, what are the testing parameters for this aspect of the wheel? Does the testing procedure realistically load this joint with the braking/drive torques that the wheels will see?

Kudos for the article series, and kudos to S.D. for sharing the information.
Keep it coming!

I'll see what I can find out.

The threads are reversed on one side of each wheel. For the front, this means the braking force will always be tightening the hubs into the wheel, and on the rear, the right side will tighten in the direction of the braking force, while the left will tighten in the direction of acceleration - IF you put the wheel on in the right direction! Durrani intends to have those who purchase the wheel sign off electronically on this issue. I don't know how subsequent owners will be informed.

When the wheels are assembled, the hubs are tightened with 2000 foot-pounds of torque. His testing shows it takes more than 1600 foot pounds of torque to break them free. (I saw them test this. It didn't break free with any degree of abruptness, if that's a word.) They may also use a chemical thread lock. (this is a correction from my earlier statement.)

The TUV testing regimen refers to torsional tests, which I now understand to mean are repetitive starting and stopping from high speeds over those many, many cycles.

Can the hub potentially overtighten and strip like a normal nut/bolt can?

My understanding is that the braking and accelerating forces of the bike will come nowhere near developing the torque levels used to tighten the "mother of all bolts" to 2000 ft-pounds in the first place. The example I was given was an engine rated at 100 ft-lbs of torque at full throttle in first gear would develop perhaps 5 times that torque, due to the force multiplication of the gearing. The idea is that 500 is just a quarter of 2000, a safety factor of 400 percent.

I'm not an engineer, so if others want to challenge that, it would be interesting to see what the response would be.

I would think that tire grip would be a limiter on how much can be applied.

Interesting...was the FEA work done with that preload in place? The center hub section seems very wispy.

I'll have to ask that question directly - check back tomorrow mid-day.. if there are any follow-on questions, add them before then, OK?


I'll try to get some pictures of the hubs - they look pretty substantial.

I'm talking about the center section of the wheel itself...it seems a bit wispy for all it's doing, but perhaps they really optimized things while doing the FEA...

Here you go:

"Extensive engineering analysis was done on this product, including Finite Element Analysis (FEA). Preload was absolutely considered in this engineering analysis where required."

Durrani made two more points:

• All engineering analysis is tempered until confirmed by real physical testing in the real world, such as is occurring right now, and
• Optimization is the name of the game.

Also, to correct something I wrote above, Chemical bonding of the hub threads is still under consideration.

In answer to an earlier question regarding finishing, a ceramic chemical conversion coating and powder coating will be applied in the same way as intended in the original design. This is described in the Wheels Within Wheels articles.

As it may seem that information is slightly incorrect. The amount of ft-lbs measured at the out surface of a tire is less than that measured near the core. I would only assume that a 400% safety factor is a bit generous.

Is there any word on the results of the test yet?

400% is a bit generous but not overly so. I would design at 200% for any critical part that can affect a life as a MINIMUM. 400% just sounds responsible.

Still no update?

Check back this weekend.

Checked back on the weekend, no update.
Will check again this weekend as well.

I got your update:

Herr Durrani made a visit to MCADX Days at Grattan todayand we got to put hands on rims. As I was walking to my garage, I saw this guy walking down the paddock with a bright green rim in his hand. As we got closer, I recognized him from a picture I had seen but before I could say hello, he says "Hold this for me" and tossed the rim towards me.

All I can say is HOLY F**K!!

I need a set for an 04 CBR1000RR and a 98 VFR. I'll wait, it definitely looks like it's going to be worth it.

saw these at the track as well-I've taken heavier sh*ts than that rim-definately on my want list-hmm maybe for when I get that R-1?