KATDASH for Better Lighting?

[Jeff in W.C.]

I've seen the ads for KATDASH, and I've read some threads and reviews. First of all, the stock bulb holder is working fine on my 1988 R 100 RT, and I have a backup unit that works well too. But, lighting at night is less than desired. So, the only reason to change to the KATDASH would be for better lighting of the instruments. I'm curious for those who may have installed a KATDASH, is the lighting much better? And, what are your thoughts on the issue? Go with the KATDASH or stay stock.

[Rob Frankham]

Before you go to the trouble the cost and bother of fitting a 'KatDash' try buying a handful of LED instrument bulbs. You may well achieve what you desire at a very low cost. LED 'bulbs' with both the large and small wedge bases are readily available. There are a couple of 'Gotchas' though.

1) Polarity - LED 'bulbs' are polarity concious... which means they won't work unless you insert them the right way round. Easy enough to rectify but a nuisance if you've put everything back together. If you're in doubt as to which is positive and which negative on the holder, check that the light works before re-assembly.

2) Charge light - Do not change the charge light for a LED unless you are going to fit a resistor in parallel. The LED doesn't pass enough current to initiate charging so the charge circuit won't work.

3) Indicator repeater - on bikes with the 3 terminal flasher relay (as opposed to the 4 terminal relay), a LED will only work one way in the indicator repeater socket.

Rob

[jackonz]

I have done exactly what Rob suggests and it is a huge improvement, as for the indicator repeater mine works fine both ways and it is a 3 pin unit, the original flasher unit died.

[SteveD]

If you like bright lights then the Katdash is likely a vast improvement. Not inexpensive though.
I tried the LED globe replacement but found more condensation occurred. Back to the usual globes and no more condensation.
The only ones I'm really interested in is the OIL & GEN lights anyhow. I might just do the OIL one with LED next time I have it open.

[Rob Frankham]

I have done exactly what Rob suggests and it is a huge improvement, as for the indicator repeater mine works fine both ways and it is a 3 pin unit, the original flasher unit died.

That's interesting, do you mind if I ask a couple of questions...

1) Was the bike originally fitted with a 3 or 4 terminal relay?

2) If a 4 terminal circuit, how did you get the repeater to work with a 3 terminal relay... there are various ways to do it but, since tthe light is connected to the 4th terminal, some element of adaption is needed.

3) If a 3 terminal circuit, Can you give an indication of the LED 'bulb' used. I've been waiting for someone to bring out a bi-directional LED 'bulb' but haven't seen one yet... I've even looked at creating my own but space considerations make it difficult.

Thanks in anticipation

Rob

[gspd]

I've been waiting for someone to bring out a bi-directional LED 'bulb' but haven't seen one yet... I've even looked at creating my own but space considerations make it difficult.

FYI - These LEDs come with a tiny device that makes them bi-directional.

[gspd]

I tried the LED globe replacement but found more condensation occurred.

+1
The heat from gauge illumination bulbs (that are on for long periods) eliminates some condensation.
For flasher, oil, brake warning and gen lights, that are normally on only for a few seconds, no difference.

[Rob Frankham]

I've been waiting for someone to bring out a bi-directional LED 'bulb' but haven't seen one yet... I've even looked at creating my own but space considerations make it difficult.

FYI - These LEDs come with a tiny device that makes them bi-directional.

Thanks for that... that's not really what I mean. What I am talking about is a simple replacement for a panel bulb (wedge fitting in the case of a BMW instrument illumination lanp) that will work bi directionally without modification to the wiring... Could easily be produced on a production line, all you would need to do is fit a bridge rectifier in the bulb between the socket and the lumiere... very fiddly, however, as a one off. Sadly probably not sufficient market to make it worthwhile.

Rob

[jackonz]

I have done exactly what Rob suggests and it is a huge improvement, as for the indicator repeater mine works fine both ways and it is a 3 pin unit, the original flasher unit died.

That's interesting, do you mind if I ask a couple of questions...

1) Was the bike originally fitted with a 3 or 4 terminal relay?

2) If a 4 terminal circuit, how did you get the repeater to work with a 3 terminal relay... there are various ways to do it but, since tthe light is connected to the 4th terminal, some element of adaption is needed.

H Rob,

The bike was fitted with a four pin terminal relay and I replaced it with a 3 pin unit, I only changed the flasher unit as after the tear down and the tidy up of the wiring in the head shell it stopped working, its a Tridon solid state unit I will have a look for you and let you know how it's wired.
I just connected it up and it worked first time, only down side is when you cancel the indicator's the repeater will flash on for two flashes, am sure my supplier here in NZ told me it will work with LED lamps as well but I will confirm that.

3) If a 3 terminal circuit, Can you give an indication of the LED 'bulb' used. I've been waiting for someone to bring out a bi-directional LED 'bulb' but haven't seen one yet... I've even looked at creating my own but space considerations make it difficult.

I don't think its a bi-directional LED lamp as I tried them on the bench prior to installation to see what side was + and so on.

Thanks in anticipation

Rob

[Rob Frankham]

Hi Phil,

Thanks for that. I understand now. Looking at the 'Tridon' flasher units and the associated wiring diagrams, it makes perfect sense.

It's worth noting that the connections and pins of the 'Tridon' unit aren't the same as those of the 3 terminal unit used in later airheads. The stock unit requires a dedicated ground connection. In this, it is like the majority of generic three terminal units and the terminals are respectively Live, Ground and Output to the switch. The Tridon unit, on the other hand, does not require a dedicated ground connection. The terminals are Live, Output to switch and Output to repeater lamp.

The important point to take away is that a stock BMW three terminal unit (and indeed, the vast majority of generic replacements), will not work in the same way.

Even though the Tridon units don't seem to be commonly available in the UK, it's worth knowing that this option exists...

Thanks again

Rob