2018 YZ-250F REAR BRAKE?

New 2018 with aprx 15hours. From time of new the rear brake has too much drag, squeals and gets super hot. I have taken the caliper apart, greased floating pins, bled system with fresh fluids etc. With the bike on stand, the wheel barely spins one revolution with considerable force. If I push the caliper over by hand releasing pad pressure the wheels spins 2-3x like it should. It seems like alignment or caliper needs shims or something ?? Any thoughts or anybody have this problem?    

If there is that much drag, then there is something wrong/defective (bent bracket, faulty caliper, etc.). Without photos, and can't really comment on what, though.

I'd contact the dealer you purchased it from, and hopefully your still under the 30 day warranty.

If you have the means I would recommend to put braided lines on, it will help with longevity and fade.

Braided or not lines shouldnt have any bearing on his problem. 

Take the metal heat shields off the pads and see how much drag you have. I had this issue with a YZ250 

Edited by Vintage Not Pimpage

also, make sure your axle alignment is good and not causing the rotor to bind, check your res fluid level; also, think about adjusting in some free play,  there is a chance you're dragging it and you just don't know it and can't feel it.

Noticed today my FX had a lot of drag on the pads and they had been wearing a lot faster than my previous YZF. Pulled the head shields off and no more drag. 

1 hour ago, Vintage Not Pimpage said:

Noticed today my FX had a lot of drag on the pads and they had been wearing a lot faster than my previous YZF. Pulled the head shields off and no more drag. 

Taking the heat shields off did not really fix your problem. they are there for a reason. 

If your hard on the brakes you will now be overheating the whole caliper. I've seen it where the caliper gets so hot that the left side will start pushing outwards unevenly. 

If you don't believe me I can send a pic of a old caliper

New 2018 with aprx 15hours. From time of new the rear brake has too much drag, squeals and gets super hot. I have taken the caliper apart, greased floating pins, bled system with fresh fluids etc. With the bike on stand, the wheel barely spins one revolution with considerable force. If I push the caliper over by hand releasing pad pressure the wheels spins 2-3x like it should. It seems like alignment or caliper needs shims or something ?? Any thoughts or anybody have this problem?    

Check your brake fluid level in the rear master cylinder. If there's too much fluid the brakes can drag. Won't release right.
3 hours ago, Edge316 said:


Check your brake fluid level in the rear master cylinder. If there's too much fluid the brakes can drag. Won't release right.

do this! 

9 hours ago, yz250f 78 said:

Taking the heat shields off did not really fix your problem. they are there for a reason. 

If your hard on the brakes you will now be overheating the whole caliper. I've seen it where the caliper gets so hot that the left side will start pushing outwards unevenly. 

If you don't believe me I can send a pic of a old caliper

 Never had an issue in 15 years of riding and racing yamahas. The replacement pads I use don't have heat shields either. 

Post up the pic I'm interested to see. 

Edited by Vintage Not Pimpage

Went thru re-checked alignment for bind. not that. Going pull some fluid out and see but did bled the damn thing 3x. The caliper gets so crazy hot.. afraid of vapor lock or burn oil or brake failure. Going to maybe check aftermarket pads which I never do always use oem pads but not sure.  Will look into heat shield removal also.  Dealer has no idea whats up with it either. 

Make sure the slider pins are lubed as well as ensuring there is a little free play at the pedal/master.

4 hours ago, Vintage Not Pimpage said:

 Never had an issue in 15 years of riding and racing yamahas. The replacement pads I use don't have heat shields either. 

Post up the pic I'm interested to see. 

Ok dude.  I will post a pic.  

On 11/11/2017 at 2:09 PM, William1 said:

Make sure the slider pins are lubed as well as ensuring there is a little free play at the pedal/master.

what do mean by free play at pedal/master?? Are you referring to pedal adjustment to foot free play? 

10 minutes ago, metalmachinery said:

what do mean by free play at pedal/master?? Are you referring to pedal adjustment to foot free play? 

Rear brake has two settings, pedal height and free play. Ideally, during setup,, the master is disconnected form the pedal. The rider sits and stands on the supported bike. The boot to pedal relationship is approximated and the pedal position is established. Then the master is reconnected to the pedal. The pin should be able to slip right in and the master clevis easily wiggle up and down with no tension (or pressure) on it.. Any subsequent pedal position change, you must ensure the free play remains. If.. you remove the free play, the masters piston can cover the bleed hole in the reservoir. This will cause break application/lockup to occur due to hot fluid and followed by a failure of the brake to self adjust.

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