Anyone having issues with brakes getting spongy when hot

[yamamarc]

Just wondering if anyone else has issues with the brake getting spongy and the lever almost touching the handlebars?
When they aren't hot it feels normal but when riding hard is when it happens.
I have a few small warranty issues so sled is going to dealer next week

 

[lilrez]

How many kms ? Try replacing fluid?

 

[yamamarc]

How many kms ? Try replacing fluid?

Over 3000km! Going to bring it in to dealer next week

 

[Crossfire12]

If I drive my car like you drive your sled, my brakes will over heat and peddle goes to floor, overheat like full throttle next corner ,brakes to floor ,floor it again hit the brakes to floor it’s operator error you’ll have to learn how to operate snowmobile. What do you think the dealers gonna say??? Say it like it is

 

[klr650r]

Done it before, but it's rare...Probably boiling the fluid, may have some water in there also. Either way just change it.
Done it twice on 120 and 129. But you gotta drive it quite hard for that to happen. Basically like you stole it in tight twisty trails to get it that hot.
Like 100% throttle to just enough brake for the track not to lock corner after corner. It's probably easier to do on longtrack sleds. I'd be willing to bet it's common for short distance cross country racers.

 

[Turboflash]

Drain and replace w DOT 4 fluid is all you can do. Make sure you use DOT 4 (not 3) as it has a higher boiling point. Also, make sure to bleed it properly. Easy to do.

 

[Turboflash]

There is also DOT 5 and 5.1 (even higher boiling points) but I'm not sure if they are compatible with Yamaha's system, meaning the seals in the system such as o-rings on caliper pistons, and seals in master cylinder on handlebar. Maybe should ask Yamaha for a ruling on that?

 

[RV125]

Changing the brake fluid to higher temp rating fluid will help.

 

[Turboflash]

Supposedly, they come stock with DOT 4. If anyone added fluid though and it was less than DOT 4, then that lowered the boiling point. Service manual recommends changing brake fluid once per year.

 

[kuvasz]

Just wondering if anyone else has issues with the brake getting spongy and the lever almost touching the handlebars?
When they aren't hot it feels normal but when riding hard is when it happens.
I have a few small warranty issues so sled is going to dealer next week

your brake rotor is warped. when your riding the piston gets pushed back. mine does this every now and again. you go to grab the brakes sometimes(not all the time) all they'll go almost to the handlebars. if you pump the brakes they're fine, right?
it happens with boosted sleds trying to slow them down.

 

[yamamarc]

If I drive my car like you drive your sled, my brakes will over heat and peddle goes to floor, overheat like full throttle next corner ,brakes to floor ,floor it again hit the brakes to floor it’s operator error you’ll have to learn how to operate snowmobile. What do you think the dealers gonna say??? Say it like it is

Never had this issue with my turboed viper with close to 10000km and I haven't changed my riding habits!!!

 

[klr650r]

Bearing might be turning on the cog shaft adding heat

 

[Pstn head]

Bearing might be turning on the cog shaft adding heat

Yup

 

[stevewithOCD]

To answer your question: NO, my brakes have NEVER faded on any Yamaha i've ever been on. This may be in part to the way i ride.
I hardly ever use the brakes.

Do you use the brakes a lot? Every corner?
If not then there is an issue as the above posts have stated.

P.S. I believe the DOT 5 has the highest boiling point, but usually has Silicone in it which is not always compatible with all systems.

 

[3UR]

To answer your question: NO, my brakes have NEVER faded on any Yamaha i've ever been on. This may be in part to the way i ride.
I hardly ever use the brakes.

Do you use the brakes a lot? Every corner?
If not then there is an issue as the above posts have stated.

P.S. I believe the DOT 5 has the highest boiling point, but usually has Silicone in it which is not always compatible with all systems.[/QUOTE