What did you do today? Cobba's rebuild

[NWS870R]

Thanks for the input Dicky. I have to get my ignition sorted first to get it all happening. Gives me time tho to throw the question on inductive or Hall effect to Koso themselves ..

The Koso UK guys are in the unit next door to me - i'll check on Monday for you Cobba

[cobbadiggabuddyblooo]

Excellent, thank you.. Some added info for those who may be interested after doing a little research on inductive or Hall Effect sensors.

Inductive work by the magnetic field inside the sensor. The magnetic field voltage increases with speed and reduction in gap so as each caliper bolt passes at a closer gap this induces a higher voltage and these isolation in voltage are used to calculate the speed .

A Hall sensor works by detecting the presence of a magnetic field when a current is placed through the conductor (sensor ) and that conductor is placed in a magnetic field perpendicular to the current flow. So every time the sensor passes over the magnets placed on the wheel disc a Hall Voltage is generated perpendicular to the sensor current and magnetic field and these pulses are used to calibrate the speed.

But there are two types of ways a hall sensor may work and that is orientated and unoriented . This would come down to the sensitivity of the device you are using this type of sensor on...
Orientated you need to make sure you have the polarity of the magnets orientated in the same direction. The reasoning behind this I would imagine keeping the polarity of voltage fluctuations uniform. A bit like connecting you speakers on a PA system in phase so each and every speaker moves out an in together. If one speaker is out of phase ( going in as the others pass outwards) this can cause cancellization of certain frequencies and ultimately affect efficiency. But it makes sense to spend 2 minutes in my eyes and just find the polarity of the magnets and place them all in phase if the Koso system uses this.

So here are the advantages of using the Hall sensor are in high speed operation over 100khz the inductive system begins to distort signal and the disadvantages of a Hall sensor are you have a larger voltage if the components are offset( not perpendicular) other magnetic fields so don't use your mobile phone while riding at 100mph while bending down and looking at the sensor, you will prob get a false speed reading , and temperature. So the last point is interesting when you think about the temps that can be reached upon the disc under brakes so may come into play if mounted on the front disc.

[NWS870R]

Thanks, science aside - i've fitted 3 types of Koso dash & they won't work without the magnets installed & they are individually marked to make sure they are fitted with the correct face pointing out towards the sensor. Can't understand why your kit has come without magnets tho? I'll check with them on Monday as promised

[Trixed]

The acewell I installed had no issues what so ever. Worked as soon as the magnet was installed. Mounted the magnet on one of the holes in the front discs.

[dicky]

Many inductive sensors are only rated to 100Hz, not 100kHz as Cobba put, but will you ever reach this rate?
Let's assume that you are going 200km/h, this is 5.55m/s
The standard 120/60R17 front tyre is rotating 3.2 times a second and the pickup is running at 19.2Hz (six bolts on the disc, times the rotation speed of the wheel)
So, no problem there then.
How about heat?
I've been running inductive sensors on rally cars for >20 years and never had one melt yet.
Have you ever had your bike discs glowing red hot? Probably not.
So, no problem there either.
Hall and inductive can be had for about the same price for the sensors, but for my money I'd go with inductive just to be rid of the hassle of fixing magnets onto the disc or wheel.

dicky.

[M.V.]

My VFR has an inductive pickup in the cam wheel for timing purposes, I'd say that thing spins pretty quickly

If you can do it without the magnets it would be a neater system

[cobbadiggabuddyblooo]

Thanks for the clarification on the sensitivity and threshold Dicky . hopefully I'll get 4 out of 5 for getting the physics right.. There was a mention of the inductive being used in such situations as on cam sprockets as an example on the piece I read on the subject too M.V.

[dicky]

These sensors are usually interchangeable, they have standard mountings and wiring so that you can swap out a Hall Effect sensor for an inductive one (or capacitive) should that tickle your fancy.
If you know anyone that works in automation they might have a spare you could play with. They are pretty indestructible. Most have reverse polarity protection and are transistorized inside so that you are seeing a switched signal at the output, not the raw sensor signal. Some even have a LED indicator at the rear to show when it operates.
RS and Farnell (or element14 as they are now known) are great sources of information on these (as well as many other things)

dicky.

[cobbadiggabuddyblooo]

Oddly enough thats where I did my little bit of research on these..

[cobbadiggabuddyblooo]

The first bookshop I went to though to do my research on the sensors was a waste of time . When I walked out I realised why...

You learn from your mistakes

[dicky]

You do realise that the Wong Fook Hing book store is not far from my place?
Takes me about 45 minutes to get there.
It actually exists.

dicky.

[cobbadiggabuddyblooo]

Small world yes I believe it .. Well I got my answer from Koso questioning about no magnets supplied and what type of system it uses. Inductive or hall sensor. There response was as follows.

" The Koso RX2-N system uses an active system that reads from the bolts." Thanks Koso International. Quick clarification on there answer and the response came back as
"Correct, no magnets are needed."

[NWS870R]

Koso UK confirmed the same - RX2-N gauge (which you have) uses an inductive sensor unlike the rest of their range which require magnets. Jobs a good 'un!

[cobbadiggabuddyblooo]

Thanks for the input guys... Much appreciated

[cobbadiggabuddyblooo]

With a little more downtime this week, I've been following along with research on what spark plug leads to use in conjunction with the Dynatek DC-3 coils I have.
With a multitude on offer I found this link very educational on the subject.

http://www.auroraelectronics.com/Unders ... 0Wires.htm

Magnecor had a similar info page as reference, but an interesting fact showed up on their official website when I looked for the Australian dist. on someone utilising the Magnecor brand but supplying a cheap and nasty ulternative so be wary.

I'm slowly reconfiguring the wiring on the bike and options I now have my sleeve are..
The good thing about the programable ignition is i can go into special settings and just disconnect the clutch and sidestand switchs.
One less potentual problem to think about.
Also with a 3 way ignition switch , I can wire it so I have ignition without the headlight circiut on.