ninjette.org

Go Back   ninjette.org > 2008 - 2012 Ninja 250R > 2008 - 2012 Ninja 250R Tech Talk

Notices

Reply
 
Thread Tools
Old August 23rd, 2020, 09:06 PM   #1
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
Boiled my rear brake fluids: practicing Gymkhana moves

I was pushing the rear brakes quite a bit practicing Moto Gymkhana figure-8 moves and I think I boiled the brake fluid. All of a sudden the rear brake pedal went down to the floor when I depressed it.

Stopped, investigated and I could not see anything wrong with it. So, I decided to head home with only the front brake in my 5 min journey. While I was heading back the rear brake slowly returned to normal.

When I got back, I flushed the rear brakes totally. I'll resume practice tomorrow and see what happens.
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote




Old August 23rd, 2020, 11:17 PM   #2
SteveL
old git
 
SteveL's Avatar
 
Name: Steve
Location: Geneve Switzerland
Join Date: Mar 2009

Motorcycle(s): BMW K1300S

Posts: 479
You must have had air in the system for it to do that.

Steve
__________________________________________________
Some mistakes are too much fun to make only once.
SteveL is offline   Reply With Quote


Old August 24th, 2020, 07:27 AM   #3
jkv45
Rev Limiter
 
jkv45's Avatar
 
Name: Jay
Location: WI
Join Date: Jul 2013

Motorcycle(s): '06 SV650n, '00 Derbi GPR, '64 CA77 Dream 305, '70 CL450 Scrambler, numerous dirt bikes

Posts: A lot.
MOTM - Jun '18, Oct '16
Quote:
Originally Posted by arthury View Post
I was pushing the rear brakes quite a bit practicing Moto Gymkhana figure-8 moves and I think I boiled the brake fluid. All of a sudden the rear brake pedal went down to the floor when I depressed it.

Stopped, investigated and I could not see anything wrong with it. So, I decided to head home with only the front brake in my 5 min journey. While I was heading back the rear brake slowly returned to normal.

When I got back, I flushed the rear brakes totally. I'll resume practice tomorrow and see what happens.
You sound concerned...

If you are using the rear brake enough to overheat it, you may want to start working more with the front brake.

It's the business-end when it comes to braking.

I use the rear only for slow speed maneuvering and low traction conditions.

With good tires in good conditions, and proper technique, the front brake should unload the rear enough that the tire's contact is minimal - and so is it's braking ability.
jkv45 is offline   Reply With Quote


Old August 24th, 2020, 07:55 AM   #4
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
Quote:
Originally Posted by jkv45 View Post
You sound concerned...

If you are using the rear brake enough to overheat it, you may want to start working more with the front brake.

It's the business-end when it comes to braking.

I use the rear only for slow speed maneuvering and low traction conditions.

With good tires in good conditions, and proper technique, the front brake should unload the rear enough that the tire's contact is minimal - and so is it's braking ability.
In Moto Gymkhana, the key to success is to make sharp turns at as high a speed you can possibly get away with because you are timed. The bike spends most of its time in 2nd gear.

I am not an advanced Gymkhana practitioner yet. So, I'm not at the stage where my skills are good enough to manage an ultra-compressed fork in a turn. Thus, my use of rear brakes for beginners, learning self-steering at speeds in tight corners.

Anyway, the issue is moot, now that the brake fluids were refreshed. No issues this morning with fresh EBC fluids.
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote


Old August 24th, 2020, 08:17 AM   #5
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T CBR250R-MC19 CBR250RR-MC22 NSR350R-MC21 VF500F CBR600RR SFV650 VFR750F R1M ST1300PA Valkyrie-F6C

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Good for you with practice! But be careful about developing bad habits that may be difficult to break later. Don't worry too much about speed on straights. Practice adjusting speed with throttle only and faster tip-in on corners. Similar to "the pace" on mountain rides, you want to set up a rhythm that doesn't upset chassis too much.

Link to original page on YouTube.

DannoXYZ is offline   Reply With Quote


Old August 24th, 2020, 08:23 AM   #6
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
That's a cool video.
Triple Jim is offline   Reply With Quote


Old August 24th, 2020, 08:32 AM   #7
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
Good vid.

Yes, no pressure on the handle-bars. Just lean and the bike will steer itself.
Let go brake half-way through turn and the bike will wake up from leaning automatically.
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote


Old August 24th, 2020, 10:27 AM   #8
jkv45
Rev Limiter
 
jkv45's Avatar
 
Name: Jay
Location: WI
Join Date: Jul 2013

Motorcycle(s): '06 SV650n, '00 Derbi GPR, '64 CA77 Dream 305, '70 CL450 Scrambler, numerous dirt bikes

Posts: A lot.
MOTM - Jun '18, Oct '16
I get Gymkhana, but dropping the front-end with front braking is going to help you get around a tight corner quicker.

This is a classic motorcycle Gymkhana video -

Link to original page on YouTube.

He has his finger on the front brake lever the entire time, and looks to be applying it smoothly when entering a turn where braking is required.

jkv45 is offline   Reply With Quote


Old August 24th, 2020, 01:59 PM   #9
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T CBR250R-MC19 CBR250RR-MC22 NSR350R-MC21 VF500F CBR600RR SFV650 VFR750F R1M ST1300PA Valkyrie-F6C

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
What's that lifting of upper-body for when he's entering corners?
I noticed he's got more upright (and narrow) bars for more leverage and taking weight off hands.
DannoXYZ is offline   Reply With Quote


Old August 24th, 2020, 05:10 PM   #10
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
Quote:
Originally Posted by DannoXYZ View Post
What's that lifting of upper-body for when he's entering corners?
I noticed he's got more upright (and narrow) bars for more leverage and taking weight off hands.
Shifting weight to rear wheels to boost contact patch and short burst acceleration.
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote


Old August 24th, 2020, 05:14 PM   #11
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
Quote:
Originally Posted by jkv45 View Post
I get Gymkhana, but dropping the front-end with front braking is going to help you get around a tight corner quicker.

This is a classic motorcycle Gymkhana video -

[...]

He has his finger on the front brake lever the entire time, and looks to be applying it smoothly when entering a turn where braking is required.
Yes, this is the famous advanced competitor with his CBR600.

It's easy to crash doing heaving pushing on front brakes into a corner; albeit, if you do it right, it's very effective. It's usually done in a smooth action: applying during pre-turn entry and letting go upon entry, followed by releasing rear brakes halfway in the turn.

I'm not there yet ... I'm a newbie to Gymkhana.
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote


Old August 24th, 2020, 05:18 PM   #12
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
Here's a more recent one using a liter bike and taller handle-bars.

https://www.youtube.com/watch?v=uaty...&index=13&t=0s
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote


Old August 24th, 2020, 05:21 PM   #13
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
This is the crazy French guy that started the ball rolling for me ...
https://www.youtube.com/channel/UCJh...0lCehzALrzF46Q

Kintaro has a whole series on becoming one with the bike rather than fighting the bike.
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote


Old August 24th, 2020, 09:24 PM   #14
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T CBR250R-MC19 CBR250RR-MC22 NSR350R-MC21 VF500F CBR600RR SFV650 VFR750F R1M ST1300PA Valkyrie-F6C

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Quote:
Originally Posted by arthury View Post
Shifting weight to rear wheels to boost contact patch and short burst acceleration.
Sure, you can do that after apex of turn and coming out. But he’s doing it before going into turn.
DannoXYZ is offline   Reply With Quote


Old August 25th, 2020, 05:17 AM   #15
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
Quote:
Originally Posted by DannoXYZ View Post
Sure, you can do that after apex of turn and coming out. But he’s doing it before going into turn.
That's what I've been saying... there's an acceleration before the curve entry point, followed by applying front + rear brakes, leaning, releasing front brakes just before entry point.
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote


Old August 25th, 2020, 07:54 AM   #16
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T CBR250R-MC19 CBR250RR-MC22 NSR350R-MC21 VF500F CBR600RR SFV650 VFR750F R1M ST1300PA Valkyrie-F6C

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Quote:
Originally Posted by arthury View Post
That's what I've been saying... there's an acceleration before the curve entry point, followed by applying front + rear brakes, leaning, releasing front brakes just before entry point.
I downloaded Jay's video and watched it in slow-mo. On acceleration sections, he's leaning forward and down to keep from wheelying. Then, he's definitely yanking up at end of straight after all acceleration has already been done. He's yanking up after braking and before diving in and turning. Maybe that's a forceful countersteering effort to make bike dive into turn.
DannoXYZ is offline   Reply With Quote


Old August 25th, 2020, 08:13 AM   #17
csmith12
The Corner Whisperer
 
csmith12's Avatar
 
Name: Chris (aka Reactor)
Location: Northern KY
Join Date: May 2011

Motorcycle(s): 2010 250 (track), 1992 250, 2006 R6 (street/track), 2008 R6 (track)

Posts: Too much.
MOTY 2015, MOTM - Nov '12, Nov '13
Respect to those who possess the predisposition to make bikes turn like that at slower speeds.

I can't get my bike to turn that sharp in the garage while pushing it. lol
csmith12 is offline   Reply With Quote


Old August 25th, 2020, 10:20 AM   #18
arthury
ninjette.org member
 
arthury's Avatar
 
Name: Arthur
Location: Sammamish , WA
Join Date: Jun 2020

Motorcycle(s): 2008 Ninja EX250J; 2005 CBR1000RR

Posts: 108
Quote:
Originally Posted by DannoXYZ View Post
I downloaded Jay's video and watched it in slow-mo. On acceleration sections, he's leaning forward and down to keep from wheelying. Then, he's definitely yanking up at end of straight after all acceleration has already been done. He's yanking up after braking and before diving in and turning. Maybe that's a forceful countersteering effort to make bike dive into turn.
There should not be counter-steering. If one is applying pressure on the handle-bars, one has missed the spirit of Moto Gymkhana.
__________________________________________________
2 Wheelers: 2008 Ninja 250R; 2005 CBR1000RR
4 Wheelers: 2018 M3; 2015 M235xi
arthury is offline   Reply With Quote


Old August 25th, 2020, 12:04 PM   #19
Alex
ninjette.org dude
 
Alex's Avatar
 
Name: 1 guess :-)
Location: SF Bay Area
Join Date: Jun 2008

Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE, '15 CRF110F, '13 TT-R50E

Posts: Too much.
Blog Entries: 7
Quote:
Originally Posted by arthury View Post
There should not be counter-steering. If one is applying pressure on the handle-bars, one has missed the spirit of Moto Gymkhana.
Huh? How do you believe the bike is flipping from one side to the other that quickly?
__________________________________________________
Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org

ninjette.org Terms of Service

Shopping for motorcycle parts or equipment? Come here first.

The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)
Alex is offline   Reply With Quote


Old August 25th, 2020, 06:52 PM   #20
jkv45
Rev Limiter
 
jkv45's Avatar
 
Name: Jay
Location: WI
Join Date: Jul 2013

Motorcycle(s): '06 SV650n, '00 Derbi GPR, '64 CA77 Dream 305, '70 CL450 Scrambler, numerous dirt bikes

Posts: A lot.
MOTM - Jun '18, Oct '16
Honestly, I'm surprised the fast guys are using such large cycles.

Since there's no significant amount of speed, and minimal acceleration area, a small light cycle seems like it would be an advantage.
jkv45 is offline   Reply With Quote


Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
How does the rear brake pad rattle clip go in place on my rear brake for 1987-2007? Wanderer 1986 - 2007 Ninja 250R Tech Talk 14 May 8th, 2017 11:26 AM
Rear Brake Lever Travel is Excessive and Rear Brake won't Lock Tire. N-m 1986 - 2007 Ninja 250R Tech Talk 14 July 17th, 2014 04:13 AM
[roadracingworld.com] - Lucas Oil Companyâ??s DOT 3 and DOT 4 Brake Fluids Ninjette Newsbot Motorcycling News 0 May 5th, 2013 08:40 PM
Fluids Xsavior 2008 - 2012 Ninja 250R Tech Talk 5 November 13th, 2012 06:21 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


Motorcycle Safety Foundation

All times are GMT -7. The time now is 01:02 PM.


Website uptime monitoring Host-tracker.com
Powered by vBulletin®
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.
Except where otherwise noted, all site contents are © Copyright 2022 ninjette.org, All rights reserved.