Homebrew01

I got a set of CR 420 wheels from a friend. Discovered they need new bearings in the rear, so I haven't ridden them yet, although i suppose I could. They are 24 spoke in the rear. I'm 170-ish, like fast group rides, crits, sprinting ...

Should I ride them, or will they be too flexy for me ? Sell them as-is, or replace bearings first ? Sounds like replacing those bearing is a bit of a pain and about $40 ?

urbanknight

All these posts about American Classic bearings going so quickly scares me with the hubs I have lined up for my next build. Does anybody know if replacing the bearings with higher quality (or ceramic) makes them last mch longer?

Anyway, to answer your question, people on teh interweb seem to thing these are flimsy wheels, yet the 3 people in real life I've ran into who ride them seem to think they're fine. One of them looks to be at least 170 lb.

Psimet2001 

I have a sprinter riding them who despises them for how flexy they are. Granted he's a genetic freak, and brother to a pro and olympic track cyclist.....and he just won Downer's Grove in his 3rd race as a cat 3....in his first season of racing......wait...where was I ? - Obviously he was hooked up with some Zipps for this one...



https://www.youtube.com/watch?v=YSLgy16CNS0

urbanknight

The hard part for me is I don't feel qualified to give my own personal opinion on the flexiness of wheels. At 150 lb with a low power output, I don't flex much at all.

JTGraphics

I have a set of AC 420 wheels non bladed model I'm 163 lbs., they are not bad but I did have spokes breaking after the 2nd, I re-spoked the rear myself with some DT Competition 2.0/1.8/2.0 have been good ever since, they also felt a little stiffer but only slightly.
Check also to see what hub you have check AC website for model hub you have bearing have not been an issue with mine so far they are light and roll very well a little flex in them not bad but I do have another set of wheels and I do fill a difference in them. Over all they are good wheels.
The CR 420's are older model if thats what you have.

bdcheung

I've had my AC 420's for a couple seasons now.

The hubs are small, and use small bearings. As a result, they're going to wear out faster. Whatever - that just means I don't put expensive ceramic bearings in my wheels.

I'd ride them. I commute on mine.

urbanknight

Are you saying that no matter which bearings I put in those things, they'll wear out quickly? So I should just stick with the cheap replacements? I plan on commuting on these wheels, too, except that I'll swap for the cheap wheels when it's wet.

JTGraphics

Same here to me ceramic bearings have a place but to me on a bike isn't one of them thats really needed.

bdcheung

It depends on what you mean by "quickly".

The bearings are small - they're going to wear faster than large-diameter bearings. Commuting puts additional stress on them. I've replaced my bearings once in the three? four? years that I've owned the wheels.

Homebrew01

Maybe AC used cheapo bearings, and getting replacements from somewhere else would be better ?

I got a recommendation for these: https://www.bocabearings.com/main1.as...n=*BRK-014C-YS @ $41

urbanknight

Thanks. That's not too bad. I've only had bearings wear out on one set of wheels for me, and that was an older-than-dirt set of Shimano 600s that I neglected to repack. My commute includes a few miles of rather crappy road, although that should change as soon as I find a house to buy.

urbanknight

That's what I was trying to ask, but BD's answer suggests that it won't matter.

BlastRadius

I have a set that I've put many 1000's of miles (at least 6-7000) on over the last 4 years. The bearings still roll smooth and I've not noticed any appreciable flex. I'm 135# and ride in California so that might have something to do with the wheel's and bearing's longevity.

lemurhouse

I have a set of AC 420's, a little over 3,000 miles on them. They have been good wheels but are indeed flexy. I'm 180 lbs, sprinter. About a month ago I started breaking spokes on the rear wheel. Significantly tightened up the entire wheel and its been OK since. More troubling is an odd whispering noise I get from the wheels when cornering hard or when heeling the bike over. Its not the wheels flexing against the brake blocks although it sounds kind of like that. I'm thinking it might be the bearings, although the wheels definitely roll fast and smooth. If anyone knows what this weird sound is I'd appreciate hearing from 'em.

Psimet2001 

Most likely the bearings. You're hearing it when they are experiencing a thrust load.

lemurhouse

Thanks. They seem ok to the touch, but that's unloaded. Is there a particular way to evaluate other than just the sound?

I guess I should probably should replace my bearings like the OP.

Psimet2001 

Can't remember off the top of my head how the hub assembly is on them, but you should be able to place the axle against something and rotate the wheel while applying some light side pressure and hear or feel something.

If not then see if it has axle end caps that come off to see if one of those shows marks from scraping.

lemurhouse

thanks/cheers

KRhea

I'm 211lbs and like to climb. I have a set of 420s on a scandium frame and really like them. I've broken one spoke in probably 1500 miles. Replaced with a DT and they're still going strong. I don't ride them everyday but when I know there's gonna be some serious "ups" on the ride I grab that bike with those wheels. I've been surprised at how well they've performed and they're much stiffer than I expected. I can really jam up a big climb out of the saddle and feel very secure with no noticeable flex, brake rub etc.

I think you have to be honest about any wheels limitations. I knew going into the 420s I was really pushing the weight/rider type limit and might experience either broken spokes, massive flexion or a set of wheels I needed to true on a regular basis, however, I was willing to take the risk and if they worked great, if not, I "should of known better". I also knew they'd never be an everyday wheel for me. They were my "light bike" wheels as well as an occasional race wheel.

I guess you could say I won the "wheel lotto" because mine have performed very well and I wouldn't hesitate to purchase another pair.


KRhea

JTGraphics

I also here this noise from the front wheel but think it’s just a harmonic noise coming thru the rim and spokes than anything. Even my friend I ride with notices a different sound coming from the wheels when I swap sets and says even when I shift he hears a different sound coming from the rear wheel nothing bad just different like a hollow sounding clunk.
I may also note that after changing all the spokes on my rear it rides smoother and truing has never been a problem with my wheels they stay just as I originally trued it when I changed spokes but I did stress relieve several times before done.

bdcheung

I got the same noise from the front wheel.

Put a drop of lube at the spoke/flange junction and the noise went away for a while, but came back.

I called AC about this and they assured me it is nothing to worry about.

calamarichris

Haha--thought I was the only one.
My bearings have been just fine, but I believe it's because I've kept them snugged up. (They tend to loosen over time.)
They've always felt a little flexy to me when mashing up steep grades, but I'm ~180 lbs. Forsooth, they're currently at the LBS, getting the spoke tension checked. Perhaps they'll be stiffer after that?

They're GREAT for high-speed flat rides, just not so good for gargantuan, clumsy behemoths going up mountains.