Fitted my Chinese brake rotors and....

[Unsane]

... it feels like they are warped out of the box!

Last night I fitted them up with new EBC pads and this morning on the daily commute began to run them in - from 30kph to stop the front end shudders and the brake lever pulsates  Just to make sure i didn't miss anything on the install, this is how it went...

1. Raise bike on centre stand with jack under engine and remove 2 caliper bolts
2. Spread pistons slightly and remove caliper (pinch bolt was not touched)
3. Remove axle bolt and drop wheel
4. Swap disc, using loctite on threads and torque to spec
5. Fitted wheel to forks loosley, lowered bike off jack & stand stand and torqued axle bolt to spec (pinch bolt was not touched)
6. Push pistons back, fit new pads and refit caliper, torque to spec
7. Pump brake lever till pressure came up

HAVE I FCUKED SOMETHING UP OR IS THIS DISC A WASTE OF MONEY AND TIME??? 

[adidasguy]

Somehow I recall a thread regarding thin crap-ese brake rotors. Did anyone really encourage you to buy them?

[Unsane]

Thanks - but was looking for some help... not "I told you so"

[BaltimoreGS]

I've run into that problem with cheap Chinese rotors on cars at work.  The only thing you can do is try to machine out the lateral run out or replace them with better quality rotors.  I don't know anyone that re-surfaces motorcycle rotors.  Have you contacted the seller?

-Jessie

[adidasguy]

I have no suggestion for what to do with a warped rotor other than to replace it.
Maybe someone else has a suggestion.

[ragecage23]

I second replacing them. When my rear disc was warped on my ninjette I just bought a new one, didn't even bother buying used.

check out cheapcycleparts.com

That's where I shop

[gsf500RR]

Maybe after some time of use the problem will stop?

[ohgood]

Maybe after some time of use the problem will stop?

or suddenly get really really bad, break, or taco completely ? funny thing about metal is, once it's warped, it never ever heals itself magically.

i'd say call it a lesson learned and toss it. you can check the runout of the rotor  by duct taping a pencil on your fork, and spinning the front wheel (after jacking it up). if there is more than 2 gnats ass' thickness of runout, it's going to suck more later. heat and abrasion will make it worse, cause handling problems, and etc

sorry

[BaltimoreGS]

I second replacing them. When my rear disc was warped on my ninjette I just bought a new one, didn't even bother buying used.

check out cheapcycleparts.com

That's where I shop

I'd try finding a good used one on here before I shelled out the money for a new one.  My 2 cents

-Jessie

[Unsane]

Strapped the dial gauge on this afternoon and found the rotor has 0.80mm run out (service limit is 0.30mm)
Removed the new disc then bolted the original rotor back on and it runs 100% true.

I will be very interested to see how eBay vendor RACINGBOY1982 wants to resolve the matter...

EDIT: I just received an email from them apologizing for the inconvenience and offered to send a new rotor. I have asked them to check this one before they send!

[Cosimo_Zaretti]

Sounds like a good solution.  I need a new rear rotor for mine (looks like you're supposed to play it on a turntable) so I was looking at those 50 buck chinese ebay jobs.  As long as the seller's are prepared to guarantee their product if you get a warped one they might not be such a bad idea.  Better than chewing up brake pads with the crap one I've got now.

Let us know if Racerboy quickly sorts out this problem.

[Unsane]

The rear disc I got from Racerboy is all good Cosimo and, in all fairness, the front disc is just as likely to have been damaged in transit
Anyways I will post the outcome 

[The Buddha]

I never have done front discs on the GS with chinese rotors, I think a few years ago they weren't even available.
Anyway rear worked great on the ones I ran, thety rust more redaily than stock though.
Cool.
Buddha.

[GAS]

Agree with buddha, I've been using a rear chinese rotor and so far so good, even better in modulation than the stock ones.


The front chinese rotors are floating rotors as the stock ones, aren't they? Wouldn't this be a rivet problem instead of real warped rotors? Maybe they're too tight and the disc isn't aligned with its center. Did you try to move the disc trying to unwarp it, while measuring?

[thejollyroger]

I would not worry about it. chinees steel is so bad your pads should where the disk out in no time

[cd]

im wondering why anyone would buy a chinese rotor when there are 20 years worth of gs parts floating around

[tb0lt]

OK... this whole thing with Chinese this Chinese that is just plain uninformed. Simply put, 99% of the time, the same universal theory applies no matter which country or continent the part is made in.... You get what you pay for. I can show 10 examples of absolute turd quality american made products for every since "poor quality" foreign product out there. No.. i'm not Chinese... i just hate generalizations based on little knowledge or here-say.

[chilloutdamnit]

OK... this whole thing with Chinese this Chinese that is just plain uninformed. Simply put, 99% of the time, the same universal theory applies no matter which country or continent the part is made in.... You get what you pay for. I can show 10 examples of absolute turd quality american made products for every since "poor quality" foreign product out there. No.. i'm not Chinese... i just hate generalizations based on little knowledge or here-say.

Gotta agree with tb0lt. There's a huge sampling bias when it comes to consumer opinion of Chinese made products. Everything is made in China and not everything can be of stellar quality.

At any rate, all brake rotors are made in China nowadays.

[The Buddha]

OK... this whole thing with Chinese this Chinese that is just plain uninformed. Simply put, 99% of the time, the same universal theory applies no matter which country or continent the part is made in.... You get what you pay for. I can show 10 examples of absolute turd quality american made products for every since "poor quality" foreign product out there. No.. i'm not Chinese... i just hate generalizations based on little knowledge or here-say.

O really ... lets see here - in 2006 I knew of someone who bought a house for 880K. That same house sold in 09 for 300. So where is the You get what you pay for there ? You want proof - Go to this site and check it out - http://flippersintrouble.blogspot.com/.

No, you pay for what you pay for, and if you're stupid you pay more for the same stupid thing. GS rear rotors usually are badly grooved, its futile to look for one that isn't. The chinese equivalent, is made with just about the same steel as the GS original, its laser cut and ironically it has potential to be better than the original, laser cut from plate is better than blanked out from plate. I call it 25 years of technology. They extract more and better steel from iron ore these days, and its cheaper, better yet, its really inexpensive to make brake rotors from grampa's old buick. If cost to manufacture + % is the standard way the prices in the world run (and I know they do) then you can easily get much better for less $ today than 25 years ago.

BTW china jails people for life for protesting on the web no less, and they work their prisoners to the bone. That eliminates 95% of the cost of manufacture.

Cool.
Buddha.

[noiseguy]

Heh. +1 for paying for what you pay for.

My biggest issue with wildcatters selling Chinese parts on Ebay is the risk I take in dealing with them. Any price I determine is going to have a "risk factor" built in; if I don't think I can recover funds or am buying "as is," then I'm much less willing to pay. Same discount for safety items, and my assessment of longevity.

I just bought an untested electrical component from a kid locally who wanted what was a fair price for a working component. I ended up paying him with Paypal, on the condition that he could expect a charge-back if it didn't work. This was a win-win: I had an enforceable guaranty of function, he got a higher price than I would be willing to pay for an untested part with no recourse.