Strange Incident in the Rain

[rhema83]

Originally posted by ulysses_sc@Dec 19 2006, 07:53 AM

Yeah, in theory. But realistically, how do you apply 30% rear 70% front?

 

I simply use the front brakes only, on the roads and on the track. Using both brakes is suppossedly the way to go, but I can never seem to stop my rear from locking under hard braking.

I almost never use the rear brake on track. My engine braking is usually strong enough to make the rear almost lock up.

[Bluetooth]

Originally posted by boogers22@Nov 28 2006, 02:18 AM

Would like your advice, as I'm trying to figure out what might have happened.

 

The other night as it JUST started to drizzle (of course this is when road are most slippery), I accelerated, then lorry in front of me brakes hard. I hit my brakes (not a complete e-brake) but with good force.

 

All of a sudden, my rear fishtails to the right a good 15 degrees. It took me a while to figure out what was going on, but I THINK rear tired got locked, countersteer and pump rear brake then it fishtails 15 degrees to the left! Luckily the lorry accelerated again and i was able to keep it upright, so I was in the clear. I'm not sure what I did wrong. Any possible suggestions?

 

I'm a new 600 R6 rider, so not sure if it was a lock but that i just not used to it? Strange thing is it didn't feel like a locked tire at all...or maybe too much power for me to handle?

The possible causes for a fishtail effect :

 

For higher capacity bikes where the weight loading is more to the front like a sport bike:

 

1) when you turn on the throttle and there is a sudden torque to the rear wheel particularly on wet roads.

 

2) when you hit brakes hard and feel a slide and counter steer.

 

Note a slide is a slide and this does not have a 'fish tail' effect unless you counter steer and try to correct it. The slide to the rear is due to the momentarily lock produced on the rear wheel.

 

To minimise the lock and slide effect, use your gearing to slow the bike down, as this ensures that there is continual momentum to the rear wheel. It also control the weight tranfer effect to the front during hard braking.

 

Beside throttle control you can tune the bike to have a smoother torque curve to make your riding particularly on wet roads less hairy or you can opt to change the gearing.

 

You can tune the suspensions too but that would be far more complex.

 

Cheers.

[skiddie_67]

I'd have to agree with most of u guys that the rear brakes are near to useless if u are thinking about slowing down ur bike. But it does however like Paitorn said, helps u to maintain the weight at the rear. Track riders rarely use the rear brakes as it is very2 hard to gauge how much force needed to step on those brake levers. More than often u'll find urself locking the rear up... If can power slide into the corner.... ok la.. stylo.. if cannot like most of us... slide into gravel...

kwakwakwa...

[paiseh]

install slipper clutch. it helps alot

[Technician III]

Hi, juz to enquire.. Wat is a fishtail like huh? I know got to do wif the rear wheel but I've nv experienced or c b4.. It's the rear wheel sliding to one side, but ur bike still going straight or other directions?

 

So when u fishtail wat shld u do huh? I know release brakes then wat to do aft tat? U guys mention countersteer? How to countersteer huh? Turn ur handle bar to the direction of the fishtail?

 

Pai seh ask so many simple qns.. I new rider, hope u guys can be patient to explain to me.. Many thanks..

 

[Dee-Jinxed]

to answer to all your questions. Go for Defensive Riding at the driving centres.

They will teach you how to control your bike when you fish tail and etc etc. and then after that, burn rubber at the circuit. haha...

[Technician III]

Hmm.. u got go for defensive riding ar? roughly how much is the course huh>

[edition]

if i nv rmb wrongly is 35 dollar .. actually bike theory book ardy teach u how to counter it ..

[Gixxer Boyz]

Defensive riding course will teach you the correct braking techniques on wet and dry road surfaces.

 

It's normal to slide on wet roads when you lock the rear wheel. The bike MUST be in the upright position when you lock the rear wheel otherwise you'll skid. Counter steering technique should be applied when you lock the rear wheel.

 

NEVER lock the front wheel on wet roads. Once you lock the front wheel the bike will wobble and when you release the brake, the wheel starts to turn and gain momentum on the wet road causing it to wobble more and impossible to control.

 

For wet surface front brake approx. 30% rear brake approx. 70%, dry surface front brake approx. 70% rear approx. 30%.

[Tourer]

Anyway I don't agree with the braking distribution part with 30% front during wet. The law of physics is the same regardless of wet or dry, because the fact is that CG(Centre of Gravity) shifts forward. The front will always have more traction under braking, and the rear has more under acceleration.

 

It may be true that you can shift some braking distribution from the like Front/Rear 90/10 on dry, to Front/Rear 70/30 on the wet (greater rear braking distri.); because wet surface might not provide the same amount of traction as opposed to how it provides on dry to hold the weight shift, but the difference shouldn't be great.

 

Besides, I never believed in Defensive Riding courses. It might provide a safer avenue for new riders to experience fish tailing in the wet, but it ultimately doesn't teach someone how to really control the bike in panic situations. Actually our motorcycles are built in a way that our steering handles will countersteer itself to its most appropriate balance under slides, attempting to correct it by force or consciousness will most often lead to over correction (unless you really go through rigorous training to perform slides) as the wobbling is faster than our hands and brain can anticipate.

 

Just my 2 cents worth. Please correct me if I said anything wrong.

[Tourer]

Infact like what many have mentioned, under many conditions, only the front brake is rendered useful due to the weight shifting under extreme braking. According to some race instructors, it would be good if you can facilitate slight rear braking under the early moments of braking when the weight has not shifted to the front, but it's a technique hard to master which would even risk more rear wheel lock ups if not tastefully done. Even many race veterans do not use rear braking under competition, they prefer not to screw up just to shred that few millimetres more.

 

To those who do not believe in applying track techniques to the road, it is probably the biggest mistake in not doing so. Because race/track techniques are the best testament to what works best under extreme conditions. Especially in the context of braking efficiency.

[louisiana]

Originally posted by tourer84@January 13, 2007 09:13 pm

To those who do not believe in applying track techniques to the road, it is probably the biggest mistake in not doing so. Because race/track techniques are the best testament to what works best under extreme conditions. Especially in the context of braking efficiency.

tourer84 I agree with you about applying brakes efficiently. You will know why I agree on this..Read on..Be warned that the braking technique I write here might not be suitable to some "bikers"

 

Firstly I'm writing here is not to offend anyone in this forum. Just like to share my riding experience here. I will try to touch on braking and stopping only.

In 1985 I got my first bike a RX-K. What I did was that I ride it for about 2 weeks. Then I took another 1 week to practice braking and stopping. And I practice this at a deserted road which is safe to do E-braking and hard braking. During the practice I will do all sort of braking combination with different speed and at a different braking point from a marker that I placed at the road kerb.

 

The braking combination I did can be eg. engine brake,front brake and rear brake...next can be engine brake and front brake....engine brake and rear brake and so on. Pressure applied on the brakes also vary. My aim is to stop before the marker without skidding the rear wheel or falling off the bike. Often I see some bikers when braking to slow down or to stop tend to first close the throttle but at the same time pull on the clutch ( as if shifting gear ). I feel that these bikers are not making full use of the brakes available.

 

Back to tourer84. I do not personally know him. Thru his posting and avatar I guess that he has some racing experience. If its correct then what I can say to you is 'Ride Safe Bro". And Don't Ever..Ever..Ever Let Your Rear Wheel Overtake Your Front Wheel. Me too during the late 80's and early 90's do some practice and sparring with my racing buddy at Pasir Gudang Track. Thru this track experience that I apply the braking technique up till now. I'm not saying that every biker here have go to any race track to know this braking technique. Let me explain how I do it that suits my riding style and bike.

 

Firstly close throttle but don't pull the clutch( engine braking ) Second apply the front brake and then lastly rear brake. At time theres no need to apply rear brake at all, engine brake and front brake when applied correctly enough to slow down or to stop. Brake pressure will depend on environment,situation and bike brake condition. But one thing that I always do is I apply more pressure to the front brake than the rear. The most important thing is the sequence to apply those brakes. Some bikers here might disagree with this. If you are comfortable with your present braking style and do it effectively the choice is yours. Lastly environmental and situational awareness etc etc..also plays a major role to a safe ride.

 

Sorry for the long post.