masi61

My buddy wore out a beautiful Absolute Black CNC milled black anodized big chainring in just a little over a year. He might have ridden 4,000 miles in that time frame. I would have thought it would have lasted longer.

I read about the Praxis forged and anodized rings and their advertising copy claims they last much longer. I’m wanting to test this out on some NOS Ultegra 6650 crank arms I bought. I was going to buy a 52/36 mid compact set and try them out.

Just curious what durability report folks are getting from their Absolute Black or Praxis replacement chainrings.

‘’Also, if anyone knows where I could obtain some (in stock) 9200 Dura Ace chain rings could you share your vendor?”

Racing Dan

I recently replaced a pair of praxis rings at barely 10.000 mi. The little one was optically worn but worked OK. The big one may have have had some more miles in it, but a pair of fresh 5 arm Shimano rings, that is also forged, was cheap enough to warrant early replacement. I believe forging is far superior to milling and turning. Cheaper in large volume and last longer. Sadly steel rings are not common.

Calsun

Forging will make for stronger parts but also more expensive to buy. CNC is a very inexpensive process and one seldom knows what materials is used. Often there is a statement as to the use of "aircraft grade" aluminum but there are many types and hardness grades and this is seldom mentioned. Marketing terms like "hard anodized" are used but it really means nothing.

yaw

I would pick forged as it should be longer lasting if done well.

Forging takes quite an initial investment and large scale production to be viable, whereas anyone can CNC on a small scale.

cxwrench

Doesn't matter how it's made, what makes the difference is what's it made out of. I would imagine forging would help any type of material last a little longer but the difference in material hardness found in different alloys is probably greater. Anodizing probably helps too.

Branko D

I've got a set of Praxis 50/34 rings with about 17.500 km on them and they still look and work fine. Have also a set of 52/36 with a bit under 4000km in pretty great condition.

Iride01 

Do you know that your buddy replaced the rings because they were actually worn or is it that he just thought they were worn?

t2p

agree - and this can be amusing

often these statements might be referring to 7000 series aluminum (compared to a lesser grade) - but even these grades of better aluminum alloys won't find their way onto commercial or military aircraft

my guess is most are not aware of many true grades of 'aircraft aluminum' - and even less have come in contact with the materials ... raise your hand if you are familiar with Waspaloy ... etc

kyle13

Forging results in a more uniform crystal lattice structure in the material, so like for like material, forged will be more durable than milled.

easyupbug 

Agree, forging greatly increases the strength to weight ratio, anodizing does not but it does allow color dyeing and helps with corrosion.

masi61

I wondered if anyone would follow up and ask that. He took the advice of the LBS mechanic on it. Honestly, I was a bit suspicious and thought they were probably OK. But my friend is not the kind of guy who replaces his chain more than every 2 2 years or so. He may have run the chainrings down by having a chain way past its prime?

Iride01 

Chains can wear out pretty quick if ... IMO... the person using them is a high power low cadence cyclist and/or rides in the extreme cross-chained positions for quite a lot of time. And excessively worn out chains will wear the cogs and rings faster.

I use to ride use the large/large combo on my previous bike with 11 speed 105. On it, I wore my first chain out quite fast with only 4000 miles on it. I didn't think I was in the large/large but just less than a minute on various climbs along my route. But none the less the chain was over .75% worn in what for me was a short time for chains. Didn't require a cog or ring change, but that might come later on the next changing of chains.

With my new bike and having Di2 using synchronized shifting, I'm never in the two biggest tooth count cogs on the rear so I'm never in the Large/Large or even the Small/Small as Di2 won't let that happen the way I have it set up. And I have noticed that I don't have any measurable wear on my chain after 5000 miles. So maybe the people screaming don't cross chain your bike or it'll blow up had the right idea, but they just didn't know the correct result or how to say it without being so offensive.

But still the above is just one experience and very anecdotal at best. Maybe more time will tell something better.