Gen1 Front Rotor Replacement Lessons Learned

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FJRBluesman

Some call me... The STIG!
FJR Supporter
Joined
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Location
Orange County, CA
I'm getting ready for a trip this summer to the Sierras and my front tire (Dunlop Roadsmart) is history, the rear is in good shape and I'll save it for future use but, for now a new set of PR2's is going on thanks to 2006FJR group buy at Cycle City in South OC. My front rotors are also shot!

At Johnny80's tech day I noticed my rotors had different colors to them and looked closely and they were heavily grooved, bummer. I had just put on some new pads a few thousand miles earlier the Galfer HH (1375) sintered pads, huge mistake. I thought the OEM pads were soft, the Galfer rep assured me they would not wear out my rotors. Well my rotors are now junk, grooved so bad they chatter with light pressure nearing a stop. No the bearings in the steering are fine etc.

Well on my 9/80- day off today, I decided it's time to change all this stuff.

Let me help those that want to or need to do this in the future.

Note: I bought all my parts online from mrcycles.com.

1. Leaving the front wheel on the bike and loosen the rotor bolts is best. I had no problem with leverage etc, better then wheel off and on the ground squirming all over the garage floor in circles, picture the 3-stooges on this one.

Grooved rotor and some loosened bolts.

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VERY IMPORTANT

The bolts are Stainless Steel and the rim is Aluminum and Yamaha used LOTS of blue Loctite!!! Be careful here.

2. Use an AIR-IMPACT wrench to remove the rotor bolts!

2 a - Make sure you have a high quality 6mm hex bit (maybe even two, one for back up) to do the job, so it fits snuggly and securely. You may even want to hammer in the hex bit lightly to make sure it's real snug and fully engaged.

I started off using a standard 3/8s wrench, no way. I got my 1/2 inch out and proceeded to break loose the first and second bolts and they were tight! The third one my bit was not seated well and it slipped out and gouged up the inner hex of the bolt, now I'm screwed.

Cooperative Bolt.

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I proceeded to get my 3/8 butterfly air-impact, it did the job quickly and easily on most of the bolts except 3 of the 12. I then got out my 1/2 in air-impact it did the trick on the other ones except the stripped one. I tried best I could but totally rounded the hole. I even tried my manual hammer impact wrench, no luck. I then got my die grinder out and ground a slot on it and used the bit from the manual impact and a large (3lb) sledge, no dice. I finally resorted to light torch heat for only a minute max to both the rim where the screw goes but mainly the screw head itself.

Tools of the trade.

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I then used the manual impact with the slot bit and after about 6 whacks with the sledge it popped! Thank God, my next resort was to grind it flush and remove it. I also broke the large slot bit on the manual impact wrench.

Not so cooperative bolt, but now it's loose.

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Now mind you, the manual calls out for 13ft.lbs. of torque. These things maybe thru lots of heat cycles and Loctite were on there like no ones business.

Now I was smart enough (which isn't saying much) to also order all brand new rotor bolts at about $1.30 each (12 total needed for both rotors), I learned that lesson years ago replacing a clutch on my old Honda Accord and the fly wheel bolts broke like butter when I re-torqued the old bolts. I would highly recommend new bolts and never reuse the old rotor bolts, all had slight deformation from removal.

New bolts.

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New bolt & Loctite next to old bolt.

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Note: If you're doing rotors and tires make sure the rotors are replaced before new tires are installed so the wheel can be balanced with the new rotors. Even if only rotors replaced it's possible your balanced wheel has changed.

Installation was real quick and easy. Make sure your hands are clean and free of any grease or oil. Don't put any pressure or weight on the new rotors, they can bend, make sure weight is on the rim. For the rotors I used some blue Loctite sparingly and installed the bolts loosely until just before seating, that way the shoulder is in and you don't tighten it anywhere to soon. Once all bolts are in, snug them down lightly with little to no pressure. Then I used my trusty torque wrench and set it at 10ft.lbs. (Yamaha torque spec 13ft.lbs.) I always do this and step it up. I set the torque (depending on the amount of torque, more gap for more torque etc) a few pounds below the recommended and then start torquing in a cross pattern until all are at the same torque and none move. I then step it up to the proper torque and do the same again. If I can feel any bolt tighten, I go around again in a cross pattern until all are at the torque and none have moved. Once none of the 6 bolts move in that sequence of torquing, then I do it one more time. That's just me though YMMV.

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Now I also have bought new OEM brakes. Before I ever install new brakes I remove all caked on brake dust from the caliper and pistons. I remove the caliper and actuate the brake lever to push the pistons out slightly. This takes a few pumps and it's easy to regulate with your fingers if one piston comes out more then the others. Make sure the other caliper has something in it, I use the old pads and a small piece of wood to fill the gap, otherwise you'll have pistons and fluid on the ground. I get the piston to a height where there is no more dirt visible then I clean them off with a tooth brush and WD40 (NOTE: make sure your rotors and brake pads are no where near the WD40). I then scrub, use a rag, and some compressed air to get it all done. Never blow compressed air directly into the piston cavity where the seals are, you may inject air and or foreign matter. Make sure calipers etc are thoroughly dried before installation.

Clean pistons.

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I then compress the pistons in for accepting of the new pads. After new pads, rotors, and wheel is installed, then bleed the brakes.

Bike on center stand and front stand.

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I bought a Black Widow front stand on evilbay, returned item from a supplier for like $37 included shipping. I used the shorter studs and it worked perfect! Easy access to the giant 19mm hex bit and axle. Great tool highly recommend this or similar unit.

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Great write up!

I went through similar pains a few months ago, And i had to get medevil on 2 bolts.

I need to replace all my rotor bolts still, And replace my brake pads.

13 ft/lbs.. yeah. ;)

 
I've found on low torque bolts, I have better luck using an inch pound torque and multiplying the torque by 12. i.e 10 ft/lbs. =120in/lbs. Nice write up and pics. The old red and blue wrench (torch) can really be your friend. Bluesman, where did you get those nice vintage Yamaha looking stickers just above your front turn signals? I can't afford an anniversary edition R1, but I might be able to spring for those. :specool:

 
Nice write up on replacing the rotors, I found that before attempting the removal of the rotors if you park the bike in the sun for an hour or so or even take it for a city ride to get the rotor bolts warm, then they let go a lot easier.

 
After 126k mi, my rotors seem to be noticeably thinner, but flat and the brakes work perfectly

Should I be concerned or measure something, etc. I only have basic mechanics tools. If I need new ones, I'd rather see if I can purchase the parts ($400) from Ron Ayers, etc

and have time for some discount deal (President's Day discount coupon would be timely)

I'm sending the bike to my mechanic soon for my new tire install, valve check, brakes check, and replacement of shock with Sasquatch rebuild

Also, I broke the pipe mounts at the centerstand which they will fix with my parts.

 
Mike, the front rotor minimunm thickness is 4.5 millimeters. Your brake guy will let you know that they're thicker than that.

If he says replace them because they're "nearly there" at 4.8mm or something, find a new brake guy.

 
Agreed. Mike - don't fix what aint broke!

And in my experience you can do much better on parts prices than Ron Ayers. Or better yet, see you if you can score some slightly used one's off the forum for cheap.

 
Mike, the front rotor minimunm thickness is 4.5 millimeters. Your brake guy will let you know that they're thicker than that.

If he says replace them because they're "nearly there" at 4.8mm or something, find a new brake guy.
I want to know before going - I need to purchase the parts ahead of time at a discount and not pay retail the shop charges

He's a Harley (Ultra) and Goldwing expert and keeps parts for those in inventory

He's very fair with labor @ $50 an hour and always counts less than actual hours

So, do I need to borrow a micrometer (or get one from Harbor Freight) ???

Is it recommended to just purchase stock Yamaha rotors, or some 3rd party ???

Thanx much

 
Mike, if your brakes are working fine, what is the issue? Why spend money you don't have to?

Again, try the WTB classifieds here on the forum. It has worked twice for me.

 
Mike, if your brakes are working fine, what is the issue? Why spend money you don't have to?

Again, try the WTB classifieds here on the forum. It has worked twice for me.
I am not comfortable "fooling around" with tires or brakes.

I want to know what the average part's life is and how to intelligently predict when there will be a failure or a decrease of effectiveness.

I don't wait till the wear bars are showing on my tires and want to know if the rotors are past normal life or getting there so I can save up and prepare to replace them.

I will look for low mileage parts, but right now I don't think I'm gonna replace them with used (I plan to ride Isabella another 125k miles)...but I never thought about used before...I know I've regretted for one reason or another putting used parts on my cars in the past. I won't be doing the work, a shop will. I'm sure they would frown upon used parts, even though they encourage me to purchase and bring parts to them for installation.

I'll ask them.

Thanx much for the posts

Mike

 
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Mike, a rotor is a rotor is a rotor. As long as its straight, it' all good. It's not rocket science.

I put 226k on FJR#1 but split those miles over two sets of wheels. On one set, I got a minor oscillation that I would feel while braking only moderately and below 20mph. That was around 100k on the bike. With the help of a friend who had the right tools (micrometer and dial gauge), we checked the two rotors on that front wheel for warpage, minimum thickness, and variance in thickness. All checked ok, so I don't know what was causing the annoyance. Brakes worked fine, just annoying.

Well, I wanted to replace so put a WTB on the forum and got what I wanted - two stock front rotors from someone who had put very little miles on them before upgrading to Galfer rotors. They sold them to me for VERY little. Those rotors lasted for the rest of the life of that wheel - approximately 65k miles, before FJR#1 was crashed and totaled.

On the second front wheel, that same oscillation started around 200k and I just lived with it. No degradation in braking, just slightly annoying. I would have found cheap used rotors for that wheel eventually.

If I were you I would find access to a micrometer and measure the thickness. As long as it is within spec, or even just a tad out, you are fine imho. Especially since you are not feeling anything unusual.

If you want or need to replace the rotors, or just have some spare than I HIGHLY recommend trying to get some low mile used ones for cheap. It's just a piece of metal.

Just for fyi, here's a pair on ebay for $115 currently though mileage is unknown: Clicky.

As for new, with a quik search I found a supplier that charges $122 ea. before shipping. I bet that's cheaper than your Ron Ayers?

If changing rotors, what I definitely would do is purchase new rotor bolts all the way around.

Remember, "If it ain't broke, don't fix it".

 
I am not comfortable "fooling around" with tires or brakes.
Then why are you trying to fool around with them?

I want to know what the average part's life is and how to intelligently predict when there will be a failure or a decrease of effectiveness.
Rotors are FOREVER. Only exceptions are very harsh pads, as in the original post, or pads worn through to the backing plate and still used, like one of our guys did to his work truck last year.

Mike, chill. If it stops smooth, the rotors are good. Even if they were too thin.

Find something else to worry about, something actually important, like what you're gonna feed a guy who can't eat shellfish, if he ever finally gets to New Orleans.

Unless you or SouthernCruizer have been using scouring pads instead of brake pads, your rotors are fine.

 
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