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WhyNot
11-08-14, 08:45 AM
You have to do an emergency stop at 70mph in the dry, in a straight line, on a 1000cc sports bike? (Aprilia RSV)

(I am asking, as I am not 100% convinced that what happened to me was normal)

Answers on a postcard :cool:
WR6133
11-08-14, 08:53 AM
A - Stop quickly

B - Lock it up but recover it and stop quickly

C - Lock it up, don't recover it and enjoy the tarmac up close

D - Don't stop in time and plough in to whatever you were trying to not hit

It's one of the above
WhyNot
11-08-14, 09:13 AM
None of your guesses Chris ;)
WR6133
11-08-14, 09:26 AM
Well as you seem too coherent to be in Hospital smacked out on morphine it definitely isn't frame snapped in half and spat you down the road so my last guess is going to be it sprouted wings, morphed in to a Lear jet and flew over the hazard...... well known Aprillia design feature ;)
WhyNot
11-08-14, 09:35 AM
I'll give you a clue, what are super bikes renowned for having rubbish ____ _____?
WR6133
11-08-14, 09:41 AM
Beyond rubbish comfort not a lot I'd expect your Aprillia to have pretty awesome brakes.


*edit* quick google tells me people have issues with the back brake on the RSV. Sounds similar to the problem on the front on my kwack which can be sorted by removing the caliper and bleeding it while someone holds it at an angle that actually gets all the air out.
WhyNot
11-08-14, 09:48 AM
Fine, answer is - 4 stoppies, in a row, maybe got about 3ft of air on the third one.

Bled the rear brakes, twice, changed original to the ducati 748 rear brake master cylinder, next stop is taking the rear caliper off, changing rear pads and giving the caliper a good service to see if that makes a difference.............

So yeah, new pants please!!
WR6133
11-08-14, 09:59 AM
So it was at least a very cool looking e-stop!

Try my suggestion above if air is remaining even after bleeding. My ZZR was awful for it brakes would go to sponge hours after being bled but bleeding with calliper off and the Mrs holding it with bleed nipple up high and agitating it a bit sorted the problem.
Trev
11-08-14, 10:45 AM
It's what I would expect on anything with forward weight bias, decent front brakes and grippy rubber - have experienced it on my less than super GSXR750 and MT03. In real emergency stop mode the rear brake is pretty much useless after the initial dab as it will usually just lock, not talking about linked brakes here of course.
wiltshire builders
11-08-14, 04:44 PM
What were you expecting to happen?
You can mess around with the rear brake all you want it won't stop the rear wheel lifting under heavy braking.
If you feel you exercised good brake control but it still grabbed too hard, you really need to look at the front brake.
Aprilias are well known for sticking callipers.
Conehead
11-08-14, 05:32 PM
Your outcome with a stoppie is perfectly correct in an emergency stop regardless of speed. The height of the back wheel depends on the speed. The rear brake is only used for stability and stopping at low speeds with the front brake. Front is 75% braking and rear is 25%.

Absolutely nothing will stop what happened to you except using less front brake but then it wont be much of an emergency.
Snowy
11-08-14, 09:09 PM
Your outcome with a stoppie is perfectly correct in an emergency stop regardless of speed. The height of the back wheel depends on the speed. The rear brake is only used for stability and stopping at low speeds with the front brake. Front is 75% braking and rear is 25%.

Absolutely nothing will stop what happened to you except using less front brake but then it wont be much of an emergency.

My personal experience is that your stopping distance is less when using a little rear brake than pure reliance on the fronts. I think the combined braking capability of say 80% front and 20% rear is more than 100% on the front only - this is due to the extra grip the rear tyre gives you in stopping your forward momentum.
Wes
11-08-14, 10:03 PM
Maybe the suspension needs looking at, im always going on about it, but it does make areal difference, especially if the front is too soft/ springs or oil needs replacing, could bottom out quicker, worthwhile getting a set up done, or at least checked over.
www.mhracing.co.uk Mark is just outside chippenham, top bloke :)
WhyNot
12-08-14, 10:34 AM
My personal experience is that your stopping distance is less when using a little rear brake than pure reliance on the fronts. I think the combined braking capability of say 80% front and 20% rear is more than 100% on the front only - this is due to the extra grip the rear tyre gives you in stopping your forward momentum.

This is my feeling also, and how I was taught in my bike training, only 2 months ago ;) If I actually had a rear brake then I would have stoppped using a combination of both, not just the front.

Also, I dont think I was particularly heavy on the front brake, if that were true then i'd have done one giant stoppie and landed in a heap on the floor, instead of four consecutive ones.....


Maybe the suspension needs looking at, im always going on about it, but it does make areal difference, especially if the front is too soft/ springs or oil needs replacing, could bottom out quicker, worthwhile getting a set up done, or at least checked over.
www.mhracing.co.uk (http://www.mhracing.co.uk) Mark is just outside chippenham, top bloke :)

Thanks for jogging my memory of the guys name, this has been on my radar for a while but I couldnt remember the company!