bschmukler

i know everyone says it's not a great idea, but i never noticed any saying anything outside of cosmetic/squeaking problems. so, i tried it. but my brakes are sticking very badly. i was riding down a hill and it jammed so bad that i flew off the bike and had to put a good amount of effort into unsticking it. does anyone know if the problem stems from the rims not being machined, my brakes or my brake pads? and how to fix it? i'm running tektro 521AG brakes on velocity chukkers. i've tried cleaning both the rim and the brakes with rubbing alcohol and taking some sandpaper lightly to the rims, though the problem is still there.

hairnet

what does sticking mean?

bschmukler

well, if i hit the brakes hard while going fast the brakes get stuck to the rim. they lock the wheel completely, and i have to force the wheel backwards by hand to break them free.

striknein

Brakes work by converting mechanical energy into heat. Your brake pads are melting because the material they're made from is too soft. Also, machined braking surfaces are left rough, which allows the rim to scrape material off them, and allows the pad to contact less of the rim surface, which cuts down on heat. Upgrade your pads, either to a cork pad or to one with a harder compound. Also, stop jamming on the brakes.

themeltingclock

Are we just going to ignore the fact that using brakes on un-machined hoops is a stupid idea? Either deal with the fact that you should not be running brakes on your current rims, or get yourself new hoops with machined faces. Simple as that.

In the future just stick to machined rims. Non-machined shouldn't be used in a situation where you would need brakes to begin with.

iBgearLess

In the past rims were never machined and brakes worked just fine. There is nothing wrong with running brakes on non machined rims as long the rims are not painted or powder coated .

striknein

Yeah no. There's no harm in it, except for the issues I already mentioned. Also, they're called rims, not hoops.

LesterOfPuppets

Huh? I've more non-machined rims than machined rims. Over the years I've had a couple of pinned non-machined ones that clicked at the seam and I've had one machined Sun that wore through prematurely, like they machined it a little too much in one spot.

Never had brakepads glue themselves to machined or non-machined rims. I've had some not want to return because they were set too low and grew a lip, but that's about it.

Scrodzilla

Thank you for your contribution. This ranks as some of the worst "advice" I've read in a while.

TejanoTrackie 

Wow! You're lucky you didn't go into orbit.

motobeCarnage 

someone please ms paint this

hamfoh

meltingclock = botbyte?

striknein

Nah. He didn't suggest "tappered breaks".

mikeetow

oh noes! my carbon wheelz have no machined surface! how do I stop

op, change your pads, go cork

Build your own

FWIW,a co-worker bought a new '10 gutterball and it came with front and rear brakes on NMSW powdercoated rims.It sounds and looks like crap, but stops fine (he's a fair weather rider, so no wet rim slippage).

mikeetow

non machined rims that are anodized or bare, like my campy shamals are fine/normal to use with brakes. The Painted rims are not the best ones to use

mconlonx

Velocity things brakes on NMSW rims are OK to go...

Shimagnolo

https://www.sheldonbrown.com/brandt/machined-rims.html

iBgearLess

As I already stated

bschmukler

yeah they are anodized, the melting is probably not aided by baltimore being humid as hell right now. what brake pads would you suggest, all the cork ones i've found are close to $100, i'm not ready to spend that much right now since i just got done paying off the bike.

Steev

Huh?
This all sounds like BS to me. One brake application enough to weld pads to rims?
Unless my reading comprehension has gone totally missing, there's something amiss, I doubt it has anything to do with pads composition or rim machining. More like brake install problems or damaged rims.

TejanoTrackie 

lolz

bschmukler

you can call bull**** if you'd like. but i don't know how else to describe it. if i hit my brakes hard particularly my back brake, like one would in an emergency situation. the brakes get stuck to the rim and lock up the wheel sometime causing further problems, like falling on my face. if i had the means of taking a video and posting it, i would. but in all actuality what advantage is there for me to be bull****ting. they are brand new undamaged rims and i've had three different people look at the installation job i did on the brakes. they are side pull caliper brakes, installation isn't rocket surgery here.

and yeah i looked at a few sites and they all were around $75, got frustrated and stopped looking. i looked again today, i found a lot cheaper ones and feel a bit foolish for giving up the search.

motobeCarnage 

hah surgery on a rocket

krusty

I'm inclined to believe it can happen. One stop on my carbon rims with stock pads (not carbon-specific) and I lost literally half the pads in melted little curlies. Wrong toe-in with a set of pads with the prominent rear 'water wiper' and flexy arms can easily make a set of brakes self-locking, so to speak. I have indeed seen it happen. It is, however, primarily an adjustment and parts quality issue, rather than an issue with the anodized rims. I have run anodized rims since the dawn of aluminum rims, and have only had issues in the rain with cheap pads. Good pads, and no issues whatsoever. All 4 of my track bikes have anodized rims, 3 of which have front brakes installed. No issues at all.