CB650F Warping front rotors

Itchytoe

2018
CB650F
Dec 15, 2019
I've had my 2018 CB650F for about a year now. It was old stock when I got it so I got a pretty good deal. Not long after I got it, I managed to mess up the front rotor due to a very unfortunate encounter with a deer. Got everything fixed and all was good for another few thousand miles, but as of late, I've noticed a pulsation from the front brakes that gets worse the harder I use them. Clearly, I've managed to warp the rotors again. Not sure how, but I did. I need to replace them, but don't really want to use the stock ones again because they didn't last too long. Is there a common front rotor and pad upgrade for the CB650F that I should look for, or do the stock rotors normally work well?
 

Devilsfan

2018
CB650F
Jun 5, 2019
Tampa, Florida
I have 8K on my 2018 CB650F and have had no issues with my rotors.

Did YOU replace them after your encounter with the deer or did the shop "fix" them?
 

miweber929

2014
CBR650F
650F Alumnus
Staff
Feb 13, 2015
Woodbury, MN
Most have no issues, but baugustine @baugustine replaced his do to noise he couldn’t make go away. I think he did EBC.

They may be warped (not sure of the “again” statement unless they warped after the deer hit and not bent) again, but that’s not typical thing to have happen.

Just to add, these are solid mounted disks, they have no floating capabilities like most do so any imperfection will be amplified.
 
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baugustine

2014
CBR650F
Staff
May 21, 2016
Ventura, CA
To follow up on miweber929 @miweber929 s assessment above, I was having noise issues at low speed braking. I replaced the pads with EBCs, no change, ended up replacing the rotors with Galfers. Noise went away until recently, now its back, although less. Rotors are most likely glazed, even with a different pad. It must be environmental (either weather or me).

My point is warping rotors takes an insane amount of heat. These are not like car/truck, where you are bringing 4500 lbs to a stop. These bikes are 450 + rider. If you were doing lap after lap on a track, I could see warping them, but not normal street riding. IF they are actually warped, either the pins are not lubricated on the caliper and the pads are making constant contact (ie never cooling off) or you are panic braking all the time (which I doubt). Check the wheel balance as well as bearings for wear
 

Itchytoe

2018
CB650F
Dec 15, 2019
I had them replaced at a Honda Powersports dealer after the deer incident. I assume they lubricated everything that needed it. I'm definitely not panic braking all the time. In fact, I consider myself easy on the front brakes. Most stops are just engine braking and a little rear brake to finish the stop. miweber929 @miweber929 You're right, again isn't the right word. They were bent after the deer encounter, not warped. I might need to take things apart and make sure it's all lubricated and maybe hit the rotors with a light sandpaper to make sure they aren't just glazed.
 

Itchytoe

2018
CB650F
Dec 15, 2019
Maybe more damage from the deer than you thought? Maybe a bent rim? Is it just the brakes or is the bike shimmying?
Nope, no shimmy at all up to the triple digits. The bike rides nice and smooth at every speed I've tried. I've put about 10,000 miles on the bike since the deer encounter. Everything was nice and smooth when I first got the rotors replaced. They've slowly been getting worse and worse. I don't notice it with very light brake pressure. I notice it more the harder I get on the brakes.
 

Devilsfan

2018
CB650F
Jun 5, 2019
Tampa, Florida
Nope, no shimmy at all up to the triple digits. The bike rides nice and smooth at every speed I've tried. I've put about 10,000 miles on the bike since the deer encounter. Everything was nice and smooth when I first got the rotors replaced. They've slowly been getting worse and worse. I don't notice it with very light brake pressure. I notice it more the harder I get on the brakes.

OK, so I would look at the brakes first, like baugustine said, before you go out and throw down extra $$$ on a new rotor. Could just be the brake pads or maybe something's not aligned on the calipers, etc.. I'd start there first.
Also, after pulling off the calipers, pull out the wheel and take the rotor off to check. You may be surprised it's not the rotor at all.

The positive...should be an easy fix with not much money having to be spent!!!
 

miweber929

2014
CBR650F
650F Alumnus
Staff
Feb 13, 2015
Woodbury, MN
Nope, no shimmy at all up to the triple digits. The bike rides nice and smooth at every speed I've tried. I've put about 10,000 miles on the bike since the deer encounter. Everything was nice and smooth when I first got the rotors replaced. They've slowly been getting worse and worse. I don't notice it with very light brake pressure. I notice it more the harder I get on the brakes.
Yeah, with 10K since the deer encounter I’d start with the calipers being sure the pistons retract and extend correctly and that the brake pins, both the sliders and pad pins, are smooth and slide freely. How old is your fluid as well?

Definitely could be rotors, and a sanding and cleaning them should help but it may be other things.
 

Itchytoe

2018
CB650F
Dec 15, 2019
Just to update everyone, I took everything apart and gave it all a good cleaning. I ended up burning through a can of brake cleaner and wore through a couple of green scrubbies trying to get the rotor and pads clean and scuffed. Unfortunately, it's been raining since then and I'd rather not take the bike out in the rain to check on brakes. That's not exactly the best time test the brake system. There's a 40% chance of rain tomorrow so I'll try to take the bike out for a ride and see if a good cleaning helped. I hope so!
Yeah, with 10K since the deer encounter I’d start with the calipers being sure the pistons retract and extend correctly and that the brake pins, both the sliders and pad pins, are smooth and slide freely. How old is your fluid as well?

Definitely could be rotors, and a sanding and cleaning them should help but it may be other things.
Calipers seem to move freely and there was no odd wear on any of the pads. Both the inside and outside pads were wearing at the same rate, and were wearing evenly top to bottom and front to back, on both the left and right sides. Fluid is the original fluid. I got the bike last summer so it's only had a single riding season on it. It is probably time to replace the fluid, though I don't see how that could cause the odd braking characteristics I'm noticing.
 

Devilsfan

2018
CB650F
Jun 5, 2019
Tampa, Florida
If you still have the rotor off take it to a machine shop to check for warping. Probably a local guy around your town. Not sure if I'd trust the mek-a-niks at your local motorcycle dealer.

And brake fluid...flush the old regardless. It's cheap and one less thing you have to do in the near future.
 

Itchytoe

2018
CB650F
Dec 15, 2019
Took the bike out for a quick ride a few minutes ago. No change at all. Still feels like warped rotor. :( I might get more aggressive with trying to clean off the rotors, but I don't know.
 

baugustine

2014
CBR650F
Staff
May 21, 2016
Ventura, CA
Took the bike out for a quick ride a few minutes ago. No change at all. Still feels like warped rotor. :( I might get more aggressive with trying to clean off the rotors, but I don't know.
Cleaning them will not solve your problem if they are truly warped. Only cure for warped rotors is true them up on a lathe or replace.If you end up wanting to replace them I’ll sell you my OEM ones if you are interested.
 

Devilsfan

2018
CB650F
Jun 5, 2019
Tampa, Florida
Well, I went ahead and bit the bullet. Got a set of Galfer rotors and HH pads on the way. A bit expensive, but should be a nice upgrade.

Did you ever check the current ones on a glass piece or have a shop look at them?

Also, when you get your new ones make sure to keep the old ones. You can have a show straighten them and have a spare set.
 

Itchytoe

2018
CB650F
Dec 15, 2019
I didn't check them against a piece of glass, but I did put the bike on a front stand to check them. Got the wheel spinning and could feel and see the rotors wobbling side to side as it turned. I do plan to keep old ones as a spare set just in case they are ever needed.
 
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