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TranceX Rider
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title - more aptly should be my Timestopper for the year 2007 but I had to overcome hurdles along the way in posting 'em here before 2008

They're just ornaments on my table for now since I haven't started building my light wheelset. Wish I could start by 2Q of this year.

The IRD has been collecting dust since summer of last year while the KCNC I've got first dibs (Dec 31 via Meyrick & Japet) from the first wave that my buddy JC brought in Manila.

IRD Ultralite MTB Alloy cassette sprockets (cogs) @153 grams; 11-32 combo

Good only for race day... short mileage of how miles, my friends?¿?

IRD's lockring @6 grams


KCNC's uber light version of its 'almost' everyday & race day cogs -- 2 Ti + 3 Scandium + 4 Aluminium @177 grams; 11-34

Not bad, I'd say esp with its claim that it's more than just a race day thing...

KCNC's lockring
@6 grams like its IRD counterpart

Hello, friends! How's everyone on this brand spanking New Year? Hope it would bring all of us great joy especially in finding gram-goon bike parts! LoL!

Here's hoping June is one of those months that go by all too fast. :D
 

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Aluminium cassettes...

i also have such aluminium cassettes. problem is they cost quite much and don't last long enough. don't expect more than 1000-1500km out of the aluminium cassette. the ones i have weigh 151g in standard version including lockring.they now come with a special hard-coating but they still wear much faster than your standard XT or XTR cassette.

however if your goal is to get the lightest possible 11-32 you can get it with some titanium cogs which brings the weight down to just 141g. instead of the 11 and 12 beeing out of steel these now are titanium (see picture below)

the KCNC is just another aluminium cassette. aluminium wears fast ! they have 7075 aluminium for the larger sprockets, scandium in the middle and just the smaller two cogs out of titanium. scandium is just another aluminium with 10% greater tensile strenght but this makes no big difference in a cassette where you just have friction wear and pressure on a small surface. so don't ecpect durability wonders out of this cassette as well: 151g

in comparison to those 2 aluminium cassettes my own titanium design is MUCH more durable while still beeing 40-50g lighter than 2008 XTR cassette.
-the "standard" version with steel 11t and aluminium spacers weighs 183g
-the "SL" version which comes with plastic spacers and a full titanium 11t cog weighs just 174g

and before D8 starts shouting out....i sell all 3 designs so no marketing for 1 specific brand or version. just giving more info on lightweight cassettes.
 

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TranceX Rider
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Discussion Starter · #3 ·
Wow! Let's trade! Joke! :D

Cuz you don't want anything but paypal... & don't want to go downtown since there's heavy traffic jam there according to you. LoL!

PM me the price for those nifty SLs... TIA!
 

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Hey Nino.

Is that design actually your own, (from your own CAD drawinds and R&D) or a cassette/s that you are buying in that is someone elses design? - If its yours did you design pitch of the teeth, the shifting ramp angle etc?

Either way, the TI cassette looks good
 

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Yeah, I bought a Forte 12-23T CNC Aluminum Cassette on ebay to try out (it was fairly cheap and 99g!). I thought it would last a lot longer, but it really only lasted a handful of rides (probably less than 10), so I would not recommend aluminum on a cassette.

I wondered if it it was the design of the cassette or the material that was the problem, so I simulated it in Catia V5 at school. I'm sooo certain that the material is just not up to the task, as it mushroomed in exactly the same place as Catia said it would.

I did a small calculation to find the load.

I weigh 200lbs. or approx 900N

load on front chainring

175mm crank arm
104bcd mm 32T chainring.

900 * 175/104 = approx 1500N

load on cassette

1500 * 32/23 = approx 2000N

I chose half this amount (1000N) because I wanted to simulate the load on one tooth and I think the load is normally distrubuted on a few teeth. Obviously, this is Back of the Envelope stuff here and is mostly for fun.

The analysis confirms most of my experiences. The cassette does feel pretty stiff (0.104mm displacement) and the design is perfect, but unfortunately in the analysis the material fails exactly where it does in real life, at the tooth. There is probably no way to design around that, so it leaves me thinking that CNC Aluminum cassettes are a waste of money.
 

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Trying to find Flow
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Hmmm. Looking at that graphic, it kind of makes me wonder if it would make sense to try to bond a hardened steel lip on just that section of the tooth that takes the brunt of the load, and leaving the rest as aluminum.
 

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Weight Maniac
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Onie said:
Any good soul out there who has the 11-32 KCNC, what's the weight of it (just for comparison)?

TIA!
Sorry, don't have an 11-32 but as you probably know it's going to be close to the 11-34....probably 160-165 grams.

My 12-27 is 134 grams.
 

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blind?

Onie said:
Any good soul out there who has the 11-32 KCNC, what's the weight of it (just for comparison)?

TIA!
just scroll up to my pictures above and you'll find the 11-32 KCNC: 151g
 

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contact...

Patriot222 said:
Nino, can you direct me to a sales link or classified? I've been searching but was unsuccessful.

Thanks
ups-i just realized that my classifieds ad is expired and gone...will put that up again later.

so in the meantime just get in touch via PM or mail - thanks!
 
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