Front rotor specs

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Dangerous Dave

The older I get, the faster I was...
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Wife and I just got back from a 2500 mile trip on the FJR...lots of mountain roads. :rolleyes: Now I've got a nasty front brake pulsation. Definately warped rotors. Went to my dealer to see about getting them replaced under YES. Mama Yama says "normal wear". BULLSHIT!!! I'm at work, my service manual is at home. Tried google and forum search without luck. Can someone with a service manual handy shoot me specs for standard and minimum front rotor thickness for an '05 non-ABS??

TIA,

 
Warped rotors are not a manufacturing defect. They will not be covered, unless they find a caliper was stuck due to defect.

 
Dave,

Per the FSM "SPEC" section, (page 2-12). front rotor thickness is 5mm, with a minimum thickness spec of 4.5mm. Maximum deflection (I assume "warp factor") is 0.1mm or 0.004 inches.

FWIW, rear brake rotor thickness is supposed to be 6mm with 5.5 minimum and .1 mm deflection.

I trust this helps!

Cheers!

 
Dave,
Per the FSM "SPEC" section, (page 2-12). front rotor thickness is 5mm, with a minimum thickness spec of 4.5mm. Maximum deflection (I assume "warp factor") is 0.1mm or 0.004 inches.

FWIW, rear brake rotor thickness is supposed to be 6mm with 5.5 minimum and .1 mm deflection.

I trust this helps!

Cheers!
Dave,

The thickness specs in my post above apply to those rotors at 298mm diameter!! Your '05 (like mine) has the 320 mm diameter rotors. The 320 mm rotor thickness spec is 4.5mm with a 4.0 mm minimum thickness. Defelction specs are the same.

Sorry for the confusion but wanted to calrify!

 
I have the service manual for an 2004, and while I don't have it in front of me, the information given in the service manual for minimum rotor thickness was incorrect.

I had a serious pulsing in the front brakes once too. Took my front wheel too a friend's who had a micrometer and dial gauge and we checked rotor thickness in about 50 places on each rotor, and used the dial indicator to check for deflection and run-out. Everything checked fine. We couldn't figure it out, and I was getting frustrated. Finally, I said fuke it and just replaced both rotors with two that were barely used that I had bought from a forum member previously that had gone to wave rotors.

Pulsing brakes fixed. So there was something wrong with one, or both, of the rotors, but we couldn't find the problem.

But when checking the rotor thickness, we measured the un-used portion of the rotor, and even that thickness was under what the service manual gave for a minimum thickness. Maybe they fixed that for the later service manuals.

I just looked it up - In my service manual for my 2004, it shows minimum thickness for the front rotors is 4.5mm, or .18 in. Maximum deflection is .1mm, or .004 in for the fronts. But like I said, that minimum thickness is wrong.

Edit: Hmmmmm........ALFJR, you're right. They list the rotor diameter in my service manual as 298mm also -which is incorrect. Where did you get the spec for the 320mm rotors? I can't find the paper I wrote everything down on, but I documented all the thicknesses I actually measured.

 
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Found my notes.

These are not ALL the measurements I took, but a good representation for each rotor.

Actual front rotor thickness measurements:

Left - .1715, .1721, 1718, 1722, 1723, 1720.

Right - .1722, .1716, .1720, .1725, .1728, .1725

As you can see, all under the minimum of .1800 in. But even the un-used portion of the rotor was under that. I didn't write it down, but IIRC, it was .175 or so.

 
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SkooterG,

Hey! My FSM has a supplemental section in the front, which I believe, is for the FJR 1300A (ABS) model. The specs for the larger rotor were on page 5 of the Supplemental SPEC section, all the way at the very front of the manual.

There are different part/publication numbers for the manual I have:

LIT-11616-17-27 and 5JW-28197-11

Cheers!

 
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Well, since the rotors aren't "worn" (both are near new spec), I'm unwilling to take the "normal wear item" answer laying down. Called the 800 #...ball is in their court. We'll see how it goes.

 
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Warped rotors are not a manufacturing defect. They will not be covered, unless they find a caliper was stuck due to defect.

Give that man the boobie prize. Mama Yama says they don't cover brake rotors under warranty. Honestly, I'm shocked and appalled. I used to be a service manager at a Kaw/Suz dealer, and have been in the auto biz for decades. Never heard of a manufacturer not warrantying rotors for warpage when they're not worn below the service limit.

Why is it everytime I try to make a warranty claim with Yamaha (including my former '04 ticker), it becomes an exercise in futility?? Building a decent product only goes so far if your customer service sucks...but I digress.

So...anybody have a STRAIGHT set of '05 rotors to sell??

 
Never heard of a manufacturer not warrantying rotors for warpage when they're not worn below the service limit.Why is it everytime I try to make a warranty claim with Yamaha (including my former '04 ticker), it becomes an exercise in futility?? Building a decent product only goes so far if your customer service sucks...but I digress.
Happens all the time, at least on my end of the biz-unless traceable to a fault in the braking system proper, the fault lies with the end user, either through ignorance (riding brakes, holding brakes constantly on down steep inclines rather than hard brake application followed by cooling period, overweight, etc) or severe usage beyond the capabilities of the system as designed (racing, high perf use with ultra hard pads, etc). ANY rotor will warp if stressed beyond it's capabilities, one only has to look at the huge brake systems used on current race machines when conditions warrant them, including but not limited to ceramics and composites. I have seen rotors even on these machines warped and cracked from the extreme heat generated. It's important to manage braking when taxing the system, using hard applications followed by cooling periods rather than constant application down a grade, even to the point of stopping short of the intended point, then allowing the vehicle to roll forward slightly so that the pad doesn't sit on a hot rotor in one spot at, say, a traffic light. The rotors on FJR's have proven themselves over many, many miles on many bikes to be up to the task for most people and their riding styles-from 2 up heavy loading to buck-plus amateur road racing to the real thing on track days-reports of failures are, at least from what I can tell, fairly rare.combine any of the two I just mentioned though, and you are pushing your luck, and not just on the stockers-there are stories of the high buck Galfers etc. failing also, but still fairly rare. Brake management is as much a skill as the rest of the riding experience, you learn, you adapt. IMHO, that is........ :p

 
Wife and I just got back from a 2500 mile trip on the FJR...lots of mountain roads. :rolleyes: Now I've got a nasty front brake pulsation. Definately warped rotors.

Sometimes pad material builds up on the rotors. The rotor isn't warped, but due to the uneven build up, it will pulse and mimic warped rotors. Consider trying the following de-glazing process. It's free and doesn't take a lot of time. Maybe no change, but then again, it might do the trick. I've seen this issue, and fixed it with the following de-glazing process.

220 grit sandpaper - in a figure eight pattern, hand sand the rotor, working from a marked starting position all the way around the rotor 3 times. Both sides, both rotors. You should be seeing some debris coming off as you sand, but not massive amounts. You will be lightly scoring the rotor, but you're not trying to make it thinner, so don't go leaning on it, just light to medium pressure and no sanding block or a flexible soft one only. (doesn't have to be 220 grit, but you don't want excessively corse or fine)

 
Another good rotor cleaner, one that removes little or no metal, are the 3M Scotchbrite pads, red is the coarsest, green the next.

 
Thanx Rad and OC for your input...good food for thought. I have nothing to lose by trying to scuff up the rotors to knock off any possible pad residue. They're otherwise trashed, so I have nothing to lose by trying. In fact, I have plenty of those little 3M Roloc scotchbrite cookies at work that go on an angle die grinder. Should make quick work of the process...maybe tomorrow on my lunch hour. I'll also take your words under advisement Rad about braking habits. I don't think I could honestly say I've not been guilty of any of the things on your no-no list, especially after just coming back from a 2-up flog-fest on the Dragon, the Cherohala, the BRP, and other misc GA, NC, and TN mountain roads. 2500 miles, and at least 1000 of those were nothing but mountain twisties. Could I have overcooked the brakes a bit?? Probably. Do I still think it should have been covered under warranty? Yes.

[soapbox]

There's a difference between agressive and abusive. It's a 2-up sport-tourer...it oughta be able to stand up to the rigors of 2-up sport-touring without having to throw away the rotors at the end of the day. I do realize that it's just my oppinion and we could debate it to death. But my oppinion is formed based on how my customers have been treated over the last few decades. I've watched Toyota warranty alot of things the customer didn't deserve for the sake of good customer relations, and almost never deny that which the customer did deserve...even outside the warranty period. For Yamaha to not step up and cover a couple hundred dollars worth of rotors (that's RETAIL price) for a 6 time Yamaha owner (3 in the last ten years) just blows my mind. Toyota would NEVER piss off a customer over something like that. And although it's been a looooong time since I worked for F&S Kaw/Suz, I know we warrantied rotors for warpage on a few Kawis. Those kind of things formed the basis for my expectations, so yeah...I'm surprised and disappointed. Other warranty issues I've had with Yamaha specifically have also preceded this incident, so I maintain that their customer service sucks. At least the rotors aren't horrifically expensive. I found them for a C-note apiece + shipping on ronayers.com

...............but I will try the Scotchbrite first.

[/soapbox]

 
<snip>In fact, I have plenty of those little 3M Roloc scotchbrite cookies at work that go on an angle die grinder. Should make quick work of the process...maybe tomorrow on my lunch hour.

<snip>

...............but I will try the Scotchbrite first.
Whoa there DD, power tools and Roloc discs are too much. Elbow grease has it's rewards here. I have access to those Roloc discs too. If you gotta, stick with the medium. DO NOT use the hard. They really will do more polishing than needed with a die grinder or drill. You want a somewhat coarse finish here in the end to help cut the pads when you start out again. You won't need to re-bed or anything like that, but it will help if there is some surface roughness instead of a polished finish.

Worth noting also is that the discs on a die grinder will develop some heat to the rotor that you really don't want if you over do it.

 
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