... 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 :mad: 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??? :sad:
Somehow I recall a thread regarding thin crap-ese brake rotors. Did anyone really encourage you to buy them?
(http://www.sportbikes.net/forums/images/smilies/lala.gif)
Thanks - but was looking for some help... not "I told you so"
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
I have no suggestion for what to do with a warped rotor other than to replace it.
Maybe someone else has a suggestion.
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
Maybe after some time of use the problem will stop?
Quote from: gsf500RR on March 16, 2011, 05:46:04 PM
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 :(
Quote from: ragecage23 on March 16, 2011, 04:55:16 PM
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
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!
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.
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 :thumb:
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.
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?
I would not worry about it. chinees steel is so bad your pads should where the disk out in no time
im wondering why anyone would buy a chinese rotor when there are 20 years worth of gs parts floating around
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.
Quote from: tb0lt on March 20, 2011, 08:37:09 AM
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.
Quote from: tb0lt on March 20, 2011, 08:37:09 AM
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.
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.
I am so sorry I didn't read and understand the original post.
K brake lever pulsating and shuddering while people say its warpage in the rotor, it actually is a thick or thin spot in the rotor. Its a manufacturing defect.
However that matters little, the fix is still to get a replacement.
Cool.
Buddha.
Well the replacement rotor showed up today - fitted it up as soon as I got home and took it for a ride to bed the pads in...
The disc is perfect - no warpage like last time - and the slotting is very agressive and feels bitey on the pads. I'm am sure the pads will wear out faster with these rotors but hey, if it stops better then I'm happy to compromise a little!
To the seller's credit, they sorted out the mess with no fuss and in minimal time. They accepted my complaint and never asked for the dud to be sent back - just sent me a new one to keep me happy... and I am
:D
Sweet! I just installed a chinese rear rotor yesterday and it's a big improvement over the horribly scored rotor that it replaced. The brake feel is much smoother and easier to control! I am so far very satisfied with it.
rear rotor I removed that from my gs the day I got never made sense to have since I never used it. sheds a lot of weight. I only used the front braks and never had an issue stoping on time. so wasting money on rear brakes are a bunch of hoopblah. morons
Quote from: mach1 on April 04, 2011, 06:46:18 PM
rear rotor I removed that from my gs the day I got never made sense to have since I never used it. sheds a lot of weight. I only used the front braks and never had an issue stoping on time. so wasting money on rear brakes are a bunch of hoopblah. morons
Well, I'll admit to rarely using my drum rear brakes on my old Hondas but the GS500 rear disc is a different matter. I wouldn't leave home without one. I always say my GS500s have dual discs, one on the front and one on the rear and both equally important. That rear disc can be your best friend when you get into a corner much too fast. Doubt you'll ever match the minimum stopping distance possible during an emergency stop with a front brake only that comes even close to a stop made using both together properly.
Quote from: mach1 on April 04, 2011, 06:46:18 PM
rear rotor I removed that from my gs the day I got never made sense to have since I never used it. sheds a lot of weight. I only used the front braks and never had an issue stoping on time. so wasting money on rear brakes are a bunch of hoopblah. morons
So was this photo taken on the day you got the bike?
(http://img8.imageshack.us/img8/2231/dsc00155g.jpg)
Maybe you should work on your spelling, punctuation and grammar before you go calling people morons :icon_confused:
Your insights on the uselessness of a rear brake are amazing mate - I wonder how every motorcycle manufacturer didn't work this out earlier?
Woot I am a moron because I use a rear brake :woohoo:
or maybe he meant mormon, with that spelling how do you guess? :dunno_black:
I almost thought it was an "April Fool".
But then realized it was posted on the 4th.
Crazy people abound... what'll that save ya? 2.5 pounds for everything (including the caliper)?
Quote from: CliffHanger on April 05, 2011, 11:25:51 AM
I almost thought it was an "April Fool".
But then realized it was posted on the 4th.
Crazy people abound... what'll that save ya? 2.5 pounds for everything (including the caliper)?
Aya, cause stopping in a shorter distance than front brake alone is highly overrated, don't you know.
Quote from: mach1 on April 04, 2011, 06:46:18 PM
rear rotor I removed that from my gs the day I got never made sense to have since I never used it. sheds a lot of weight. I only used the front braks and never had an issue stoping on time. so wasting money on rear brakes are a bunch of hoopblah. morons
I hope you never encounter stop and go traffic in a slope.
Quote from: CliffHanger on April 05, 2011, 11:25:51 AM
I almost thought it was an "April Fool".
But then realized it was posted on the 4th.
Crazy people abound... what'll that save ya? 2.5 pounds for everything (including the caliper)?
Not that its relevant, but it's weight shaved from the rotating mass. Same as drilling speed holes in a steel sprocket, 520 chain conversions, lightened crankshafts, smaller tires, etc.
Quote from: mach1 on April 04, 2011, 06:46:18 PM
rear rotor I removed that from my gs the day I got never made sense to have since I never used it. sheds a lot of weight. I only used the front braks and never had an issue stoping on time. so wasting money on rear brakes are a bunch of hoopblah. morons
It is bothering me that you can't say c@%t, f%$k or shaZam! on this forum, but you can give all sorts of advice that's going to get people hurt. There's people saying that you should never use the rear brake ever and you should actually remove it, and then there are those saying that you shouldn't be making emergency stops on the front brake because if you lock it you'll wash out the front and drop, so avoid the front brake kids. Combine this with the number of morons on the internet who don't even understand the physics of how a motorcycle turns who nonetheless dispense advice on cornering and a self taught motorcyclist with access to the internet becomes a pretty dangerous proposition.
Whilst it's true that the front brake's the one for stopping the bike quickly in a straight line, you need both brakes, you need to be taught how and when to apply each one, and you need to consciously practice using both in a variety of circumstances. Correct use of the clutch and rear brake is key to all your slow speed manoeuvring, and you're going to be another rider who inexplicably drops bikes in carparks and petrol stations until you get it properly susssed out. Or you'll spend a lot of time awkwardly duckwalking your bike around cos you can't control it slower than walking pace. You want to save weight on your bike? remove the 150lbs of moron perched on top until you figure out how to ride.
You may want to sometimes
gently trail a little rear brake if you've overcooked a corner, emphasis on the gently, preferably without easing off the throttle. I'll let you off since I assume you come from some boring part of the world that doesn't actually have any corners. Obviously it's preferable to just lean in harder and keep rolling on, but some days you just run out of balls.
Honda had it sorted a generation ago, although it didn't really survive the translation.
Quote5. Go soothingly on the grease mud, as there lurks the
skid demon! Press the brake foot as you roll around
the corners, and save the collapse and tie up.