Jump to content

Replacing the Idiot Lamps


Kiwi_Roy

Recommended Posts

I highly recommend replacing the incandescent lamps and lamp-holders with LED type bulbs. I have done this on several bikes now with good results

 

 

To get the screws out remove the gauges then you can grip the brass inserts with a pair of pliers while undoing the Allen screws, don't worry if the plastic gets broken a bit JB Weld is your friend.

 

I really like the type 194 single LEDs from www.superbrightleds.com, they are an AC lamp (have a built in bridge rectifier) so you don't have to worry about polarity and they glue nicely into the fitting.

You need to select lamps to match the filter colour otherwise they won't show through properly

 

The low fuel light is a special case, even when the tank is full the sensor is drawing a small current, if you just replace the lamp with an LED it will be on because the small current is more than enough to light an LED, The original lamp and sensor are a fine balancing act, when the sensors uncovered it heats up and drops in resistance, the lamp starts to heat up and goes up in resistance.

The easiest way to deal with this is simply wire the LED in parallel with an original lamp, this gives the thermistor sensor the current it is used to, the extra load the LED draws is insignificant.

 

Another thing you might notice is the oil light coming on in the rain, this is because the current tracks across the dirt of the pressure sensor the LED draws so little 5 milliamps is enough to turn it on, wiping the switch clean is usually enough to let the lamp turn off probably some CRC or a cover would help.

 

The pictures below are from two different projects, sorry if they seem out of sequence.

 

Here's what the original light fitting looks like complete with cracked screw holders

CIMG6110_zpsa2d10f91.jpg

I throw those nasty lamp-holders away. The brass inserts were spinning at this point but you can see they are easy to grab with needle nose pliers.

CIMG6107_zps1b65c17a.jpg

 

Some Ty-wraps to take the strain off the wires, the wires are just soldered direct to the bulbs, I tried using the appropriate sockets but they just add extra stuff to go wrong.

4AttachWires_zps04df76fb.jpg

At the bottom in a piece of white heat shrink you can see the old incandescent lamp in parallel with the Low Fuel LED

 

The next two pictures really belong in the Speedhut gauge thread. 

3Lampholder_zps77209e03.jpg

 

The lamp fitting in this case has been reduced in height to take advantage of the Speedhut Gauges that are only 1" high.

 

1ShortCover_zps822a2df2.jpg

A corresponding amount was taken off the cover, I used a strip of 3/4" masking tape as a guide and chopped the lump off where the speedo gears were smoothing it off with Bondo.

Link to comment
Share on other sites

I highly recommend replacing the incandescent lamps and lamp-holders with LED type bulbs. I have done this on several bikes now with good results

 

 

To get the screws out remove the gauges then you can grip the brass inserts with a pair of pliers while undoing the Allen screws, don't worry if the plastic gets broken a bit JB Weld is your friend.

 

I really like the type 194 single LEDs from www.superbrightleds.com, they are an AC lamp (have a built in bridge rectifier) so you don't have to worry about polarity and they glue nicely into the fitting.

 

 

 

WORK IN PROGRESS

 

I am going to do this. In the 'Looking at 2000 V11 Sport" thread, you mentioned that the fuel light needs a "special arrangement"

 

What do you mean by this exactly? 

Link to comment
Share on other sites

If the little screws are spinning, you will need to remove the plastic cup that covers the gauges so you can access the plastic T-shaped lamp holder from the other side. You may be able to force a drywall screw into the back of the brass threaded inserts to stop them from spinning - this will do less damage to the lamp holder than the pliers will. Or you could order a new plastic T (with threads included).

Link to comment
Share on other sites

From memory I think I did as Scud mentioned but grabbed the inserts with a pair of needle nose pliers from the back side, one leg of the pliers in the hole the other gripping plastic squeezing the two together. Refer to the second picture you'll see what I mean.

 

 

 

 

Craig, can you remember how you dimmed the bulbs, a resistor about 2-5,000 Ohms I would think.

 

It would be possible to have a lower Voltage common supply on the Red/Black wire with Day and Night settings but I rarely ride at night these days.

The direction indicator LED might be more difficult.

Low fuel should be bright, besides it never sees full Voltage.

Link to comment
Share on other sites

The only decent way to dim an LED is by PWM of the voltage.  PWM = Pulse Width Modulation.  Typically done at higher frequency, so you don't see any pulsing or flicker.  Basically, it's like chopping up the incoming 12V into a bunch of ons and offs, but with a specific duty-cycle. 

 

And the weird issue with the fuel light is that the bike uses an NTC.  Basically it's a resistor, but when it's wet with petrol, it sheds it's heat into the petrol.  When petrol drops, NTC "gets hot", and it's resistance goes down.  This is why you see the lamp glow, then turn brighter.

 

NTC is opposite what normal resistors do.  (Inverse heat/resistance curve.) 

Anyway, the NTC NEEDS some current flow to get hot, and the bulb allows the proper flow, whereas, an LED cannot produce enough current flow to make the NTC behave as designed.

Link to comment
Share on other sites

Craig, can you remember how you dimmed the bulbs, a resistor about 2-5,000 Ohms I would think.

The only decent way to dim an LED is by PWM of the voltage.  PWM = Pulse Width Modulation.  Typically done at higher frequency, so you don't see any pulsing or flicker.  Basically, it's like chopping up the incoming 12V into a bunch of ons and offs, but with a specific duty-cycle. 

 

Stick is correct unless you are creative.  I put two layers of painters tape inside the transparent housing over the high beam and flashers.  I happened to have blue painters tape and green painters tape lying around.

Link to comment
Share on other sites

 

Craig, can you remember how you dimmed the bulbs, a resistor about 2-5,000 Ohms I would think.

The only decent way to dim an LED is by PWM of the voltage.  PWM = Pulse Width Modulation.  Typically done at higher frequency, so you don't see any pulsing or flicker.  Basically, it's like chopping up the incoming 12V into a bunch of ons and offs, but with a specific duty-cycle. 

 

Stick is correct unless you are creative.  I put two layers of painters tape inside the transparent housing over the high beam and flashers.  I happened to have blue painters tape and green painters tape lying around.

 

Guzzi guys and analogue solutions! :grin:

Link to comment
Share on other sites

 The only decent way to dim an LED is by PWM of the voltage.  PWM = Pulse Width Modulation.  Typically done at higher frequency, so you don't see any pulsing or flicker.  Basically, it's like chopping up the incoming 12V into a bunch of ons and offs, but with a specific duty-cycle. 

 

And the weird issue with the fuel light is that the bike uses an NTC.  Basically it's a resistor, but when it's wet with petrol, it sheds it's heat into the petrol.  When petrol drops, NTC "gets hot", and it's resistance goes down.  This is why you see the lamp glow, then turn brighter.

 

NTC is opposite what normal resistors do.  (Inverse heat/resistance curve.) 

Anyway, the NTC NEEDS some current flow to get hot, and the bulb allows the proper flow, whereas, an LED cannot produce enough current flow to make the NTC behave as designed.

 

And the incandescent lamp is just the opposite when it's cold the resistance is low so it applies almost full Voltage across the thermistor

This is the reason I use one of the old lamps in parallel with my LED the lamp applies the full 12Volts across the thermistor until its uncovered.

It's a fine balancing act between bulb heat and thermistor heat.

 

Really it would be much better if our bikes had one of the magnetic float and reed switch sensors some of the other Guzzis have.

 

Interesting point about dimming the LED with pulse width modulation, the eyes are fooled by a fast flicker, have you tried that?

I like it that the LEDs are visible in bright sunlight and I rarely ride at night, with old age I find I get very disoriented in dim light.

Link to comment
Share on other sites

I have not messed with the incandescents that are in there.  I have built a PWM controller for my home-made heated gear, but I have that one running at about 3 Hz, so that you can "see" where the channel is set at a glance.  The ones you buy, it seems like you have to look at the controller for about 1 or 2 seconds to figure out the setting.  I like mine better, because it keeps my eyes on the road. 

Link to comment
Share on other sites

  • 1 month later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...