Speedo : Description
The Fazer features an electronically driven speedo.
The front wheel drives a rotor unit which rotates within a sensor unit which is fixed
within the wheel hub. From this sensor unit, electrical impulses are transferred to the
speedo unit via a 3-core cable which runs alongside the left-hand brake hose into a
terminal box under the fuel tank, and from there to the speedo unit itself.
Speedo : Cautionary Notes for Front Wheel Removal/Replacement
As mentioned, there are a couple of sensitive devices related to the speedo located
within the front wheel hub, and care must be taken not to damage these when removing
and replacing the front wheel, as follows.
When removing the wheel, after first removing the wheel spindle, roll the wheel
backwards slightly to get the speedo sensor unit clear of the fork leg bottom, before
removing the sensor unit from the wheel.
The reason for rolling the wheel backwards is that rolling it forwards runs the risk of
overstretching, and damaging, the cable from the sensor unit.
When replacing the wheel, ensure that the lugs in the rotor unit are correctly located
in the appropriate slots within the sensor unit. One of the most commonly reported
faults with Fazer speedos is the lugs being snapped off as a result of these not being
correctly located before the wheel was re-fitted. With these lugs missing, the rotor
will no longer rotate with the front wheel, leading to speedo loss.
If you do happen to be unlucky, and break the lugs, it's not all bad news, though. The
rotors are available for under £10 UK (2003 prices) from Yamaha; the part number you
need to ask for is 5VU-2517G-00-00)
(Used to be 4YR25-17G00-00 but apparently that changed in 2004 - seems they upgraded the part. Not before time).
Once the wheel is in, and the lugs are safely where they are supposed to be, pay
special care to the routing of the speedo cable. Another common problem is for the
cable to get routed between the left-hand caliper and the disc, in which position the
disc mounting pillars (on which the disc floats) can rub on the cable. In very short
time, they will wear through the cable, and you'll have a faulty speedo sensor unit.
Unlike the rotors, these aren't cheap - I've replaced one and it cost me over £65. So
pay attention to where the cable goes.
Speedo : My Speedo's Playing Up
(Formerly known as 'Speedo : Fault Diagnosis')
Symptoms
It's quite rare for the speedo to just conk out. What more usually happens is that it will start to show erratic readings - often dipping down to well below your current speed, and sometimes flying up to a silly speed - I saw well into treble figures which, as we all know, is a part of the speedo that Fazer riders never normally go near.
So if your needle's doing this, it's an early sign that things need looking at.
Fault Diagnosis
The main culprits that I am aware of are covered in 'Cautionary Notes'
above - the rotor, the sensor and the cable. To that list you can add the speedo unit itself, although this is a rare one, and if that's what it turns out to be, you've been unlucky.
First, though, you need to rule out the others.
The first question to ask is 'has the wheel been off lately' (and by 'lately' that could be anything up to 3 months ago)? If so, have a read of 'Cautionary Notes', then start working your way through.
I'd start with the cable, because this is easiest to check without dismantling the bike too much. Check it's not been routed so anything that spins at front wheel speed can chafe through it (disc mounting bolts and the pillars between the fixed and floating bits are common culprits). Apart from that, have a look for signs of obvious damage - cracking of the insulation, that kind of thing.
If you find anything, get it sealed up quick and route the cable so it can't happen again.
If all's ok there, the next step involves taking bits off, and here you've got a choice.
You can either test the sender unit - by putting a multimeter on the end of the speedo cable, which involves lifting the tank to get to the cable connector (it's in a plastic box with lots of other connectors) - readings can be found in Resistance Readings for Good Speedo Sensor below. But only bother doing this if there's no movement at all on the speedo needle. If it's working intermittently, then a good set of readings won't really prove anything.
Otherwise, you can drop the front wheel out and check the rotor and sender for physical damage. The rotor unit is a very common culprit; as you've probably read by now, the usual problem is that on reassembly after wheel removal, the lugs aren't properly located in the sender, and get snapped off. If it's only that, consider yourself lucky - you can get a new one for under a tenner (part number 5VU-2517G-00-00).
If it's not the rotor, and the sender has checked out ok (resistance-wise) and shows no sign of obvious damage, well it could be the speedo unit itself. Got no idea how to test those things (short of finding another Fazer owner and substituting one for the other, which I would not do, to be honest - if it is faulty, and the fault was caused by something further on in the wiring, then you risk blowing the good one too - now it's getting expensive.
Best I can suggest is it's time to go see the dealer, I'm afraid.
Speedo : Resistance Readings for Good Speedo Sensor
In the event of speedo sensor failure, it's often difficult to tell if the fault is in the
sensor, the wiring, or the speedo head itself, and with a replacement sensor likely to set
you back something upwards of £65 (that's what I paid for one in summer 2001) and the
speedo heaven knows what, you don't want to be buying things that may not need replacement.
Trouble is, the manuals aren't exactly stuffed with useful info for diagnosing problems
with these things. So after I got my replacement, and before fitting it, I stuck an
avometer across my good one to get some reference readings.
If yours is playing up, and you can lay your hands on a meter, take measurements as below.
If your readings vary much from mine, then the sensor is probably faulty (but bear in mind
these were taken with a meter that hadn't been calibrated for years, so check for readings
in the order of those shown, not exactly the same).
Readings
My sensor has red, black and white wires on the 'wheel' side of the connector; blue,
black and white on the 'bike' side. The measurements were taken on the 'wheel' side (ie
measuring the sender, not the motorcycle wiring).
The first wire in each pair below is the one the avo +ve lead (red) is connected to; the
second the one the Avo -ve lead (black) is connected to.
Resistances are in ohms; figures are what I saw, but bear in mind this avo hasn't been
calibrated in years, so yours could be different, but basically you're looking for the
same order of things; similar, not exactly the same. I'm sure you get the picture.
Avo +ve
Avo -ve
Resistance
Red
Black
No needle movement (>200K ohms)
Black
Red
20K ohms (approx)
White
Black
1.5k ohms (approx)
Black
White
No needle movement (>200K ohms)
Red
White
No needle movement (>200K ohms)
White
Red
100k ohms (approx)
As I say, the readings are approx; if the sensor fails (as mine did) you can expect to
see something very different to those readings.
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Speedo : Failure of Speedo and Tacho when lights on
Someone sent me this a while back; I'm really sorry, but I can't remember who it was (and forgot to make a note).
Let me know, whoever you are, and I'll put your name here.
I dunno how common this is, but I had an electrical problem whilst in France that reappeared a few weeks ago!
Problem: Switch on ignition, clocks and tacho work fine. Switch on lights aswell - clocks (odo and clock) and tacho die! An anoying short.
Cause: Under fairing, left hand side, the clocks plug into the loom. Check prongs on the big white plug. Some of the prongs on mine were corroded, making a dodgy connection.
Solution: Unplug big white plug, clean off corrosion, lube and replace. Sorted
Speedo : Problems with the Odo/Clock Reset Switch
Courtesy of bigralphie:
I have just fixed my reset switch and I know other people were having problems, so here is how I did it.
The switch has 3 parts , a rubber gaiter with a rubber cylinder that extends when you press , a plastic connecting piece and the tact switch on the PCB.
The switch is difficult to use because the connecting piece will have moved and is not sitting square.
Get a pair of long nose pliers and a some like a long tack or slim nail etc.
Prise out the rubber gaiter/button in the hole you will see the connecting piece it has a matching cylinder on a square base.
The cylinder has a hole straight through it.
NOW THE FIDDLY BIT.
Use the tack or slim nail and carefully push it into the hole in the connecting piece. Gently move the connecting piece with the tack so its fully square over the tact switch (you can feel it locate) No use the pliers the apply a little more force to secure the connecting piece but don't over do it. Refit the gaiter and test you should find you will feel a positive click when you press the reset.