Sunday, 28 December 2008

Which brake pads to choose for your sportbike?

Choosing the right brakepads for your sportbike

When I am looking in my owner's manual they do not mention anything about which brake pad to choose (off course, they want you to go to the dealership and have them changed with oem brake pads). Is that really the best way? What about all these different brake pads manufacturers all claiming to be the best? Have you ever experienced after changing brakepads that they were not at all what you expected out of them? Here is some insight on choosing brake pads for your application:

Let's look at how a brakepad is made.
Resins are used to hold the brake pad materials together such as the friction materials being fibreglass, kevlar or arimid. Steel and aluminum maintain the heat stability. There is also filler material such as saw dust. Sometime graphite is added to adjust friction level depending on temperature range of use.

Molding process
Are the pads pressed in a mold one by one or mass pressed? High performance brake pads are pressed one at a time. This would be more durable as the full pressure was applied.

Are the brake pads slow cured or rapid cured?
Usually after pressing the materials in the mold the brake pads go in an oven to remove moisture that is present in the friction mixture. Needless to say, slow curing is always better. rapid curing of the pads can put stress on the friction material by the moisture escaping too fast creating small cracking.

The codes on Brake Pads steel backing plate
The codes refer to the friction formulation and show the consumer its ranking in the chase test.

What is the 'chase test'?
This is where those two letter designation come. The chase test is assigned to add a two letter code that we often see on brake pads. EE, FF, GG, HH. Those letters specify the coefficient of friction when a 1" square piece of friction material is subjected to varying conditions of load, temperature, pressure and rubbing speeds on a chase machine.

The first letter refers to the normal friction coefficient. The second letter refers to the hot friction coefficient based on the fade and recovery test. Brake fade is when you notice brake power is less efficient. Recovery is where your pads are cooling down again.

H has the highest coefficient of friction. (superior braking power)

The friction coefficient codes are as follows:

C = < d =" 0.15" e =" 0.25" f =" 0.35" g =" 0.45" h =" "> 0.55

Now you would think that HH is all you need. Wrong. H might be braking to much if you're only commuting.Racing pads might never reach to the right working temperature... It's pretty much up to you which brake pad is best for you.

I am happy with EBC Sintered Double-H pads. Great pads, if you follow the break in guidelines you will stop a lot sooner and safer. Combine this with stainless steel brake lines and braking will be excellent. Break in: 10 stops from 80 to 40mph. Use some 220 sandpaper on the rotors to remove old pad residue.

Other Brake Pads
DP Race Compound Pads
Galfer HH Braks Pads
Carbone Lorraine SBK3
Ferrodo 911 (Sintergrip)
Vesrah RJL

Yamaha YZF R1: The right tire air pressure

On the 2005 Yamaha R1 one can find the label on the swing arm with the suggested tire air pressures for front and rear wheel. If that label is no longer there, you can look in your owner's manual. Anyway, my label and owner's manual read:

Tire air pressure (measured on cold tires):

Loading condition:
0–90 kg (0–198 lb)
250 kPa (36 psi) (2.50 kgf/cm²)
290 kPa (42 psi) (2.90 kgf/cm²)

Loading condition:
90–202 kg (198–445 lb)
250 kPa (36 psi) (2.50 kgf/cm²)
290 kPa (42 psi) (2.90 kgf/cm²)

High-speed riding:
250 kPa (36 psi) (2.50 kgf/cm²)
290 kPa (42 psi) (2.90 kgf/cm²)

The above list looks very elaborated however at first I thought there was a printing mistake. They do list 3 possible tire air pressure combination; weight of the driver and riding style, but the advised tire air pressure in all three is the same..... 36psi in front tire and 42psi in rear tire.

After searching around I see that different people (light weight or heavy weight people) have different opinions and preferences. It looks like the truly best tire air pressure is 36psi in front and also 36psi in rear tire. This off course would be for street set up (commuting) maybe on the track you would set your rear tire on a higher pressure however this would mean less traction. This is one you have to experiment with. Give me some feedback what your best numbers are.

Wednesday, 24 December 2008

Yamaha YZF R1 losing tire pressure

I hate it, when I got the bike, the first time I drove it, it felt really weird, it wanted to keep going in a straight line. After visiting (best site on the subject) I got some good pointers. The reason was almost so obvious I totally ignored it: tire pressure. I measured only 12psi in front tire and 15psi in rear tire. Gosh... Problem is I pumped air in the tires to spec (36psi in front 42psi in back), the day after it went down like 5 psi. I hate this stuff. What does this mean? Do I have to change the tire or valve? I have to figure this one out what the cause is. Maybe I should just put a tube in to avoid this in the future.

Tuesday, 23 December 2008

Yamaha YZF R1 paint fairing with spraycan

You would think i am crazy to spray my beloved yamaha R1 with spray cans, but tell you what, I would be crazy to buy brand new fairing parts from the dealer just because the fairing has some scuffs. I had excellent results with Krylon and Plasti Kote spray cans. I used the Krylon BBQ & Stove spray can for the exhaust can heat shields, I must tell you, I was impressed. It looks like brand new. I used the Krylon Bumper Spray for the side fairings. I have chosen the flat black since the bike is the raven version. Excellent results again. Now I just have to guess how long the paint finish will last, but who cares, If i got a scratch on it, I just have to go get a can and spray over. I don't think you can go wrong with that. i will updated pictures on another posts. Has anyone else had good results spray painting your motorbike with cans?