BMW K bikes (Bricks)


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1Back to top Go down   LED Indicators Empty LED Indicators Wed Jun 21, 2017 4:42 pm

AndrewP

AndrewP
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Hi everyone,

Little help required please.

I want to put LED indicators on my 1989 K100 project, I have connected them up and they just light up, they don't flash at all and a beep sound comes from what I think may be the relay ??

How do I make them flash.

I have the tail/brake light changed to LED no problem.

Any help would be much appreciated Smile 

Andrew P

    

2Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 6:42 pm

MartinW

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Inge has a mod that involves cutting one of the tracks in the relay. I tried to post the link but for some reason it would not load. Inge will probably post on it.
Regards Martin.

    

3Back to top Go down   LED Indicators Empty Ballasts Wed Jun 21, 2017 7:04 pm

tagaz

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Have you installed ballast/balancing resistors for the new lights?

Without the load balancing resistors the circuit is a Short Circuit & will usually blow the fuse.
Led's have little or no resistance of their own.

HTH,

Troy

    

4Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 7:10 pm

robmack

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How to construct your own DIY LED relay but also includes pictures of where to cut the traces on the OEM flasher relay to adapt it to LEDs.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

5Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 7:22 pm

kioolt

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Tagaz

Are the resistors wired up in parallel to the LED bulbs or in series?


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

6Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 8:26 pm

tagaz

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series

as a quick test use a jumper wire and connect the old incandescent bulbs in series with the leds.
should work as if you had the old lights installed with the additional leds functioning as well.
the circuit will see the led's as if they were just wire. that is they will not cause any additional resistance to the circuit.
but will draw current, so maybe a fuse will blow. or maybe not. as always YMMV.

i have a incandescent signal bulb & tail/stop bulb that i soldered some lengths of wire onto for use as test lights. 

hth,

troy



Last edited by tagaz on Wed Jun 21, 2017 8:45 pm; edited 2 times in total

    

7Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 8:35 pm

AndrewP

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tagaz wrote:Have you installed ballast/balancing resistors for the new lights?

Without the load balancing resistors the circuit is a Short Circuit & will usually blow the fuse.
Led's have little or no resistance of their own.

HTH,

Troy
Hi Troy,

Tried to put resistors in and yes blew the fuse : (

I'm having another go at putting them inline ( saw it on youtube ) see if this works. If not I will post up some pictures to see if someone can help, electrics are not a strong point of mine Smile

Andrew

    

8Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 8:38 pm

AndrewP

AndrewP
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robmack wrote:How to construct your own DIY LED relay but also includes pictures of where to cut the traces on the OEM flasher relay to adapt it to LEDs.
Hi Rob,

I did see this but its waaaayyyyyyyy out of my league  Very Happy Very Happy

Andrew

    

9Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 8:40 pm

kioolt

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Could you describe for me what series is to you?  I've only seen instructions for wiring the resistors is parallel.  We are talking about LED bulbs made to operate on 12VDC aren't we?


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

10Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 8:50 pm

tagaz

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kioolt wrote:Could you describe for me what series is to you?  I've only seen instructions for wiring the resistors is parallel.  We are talking about LED bulbs made to operate on 12VDC aren't we?
Ohms law:

series = sum of all resistance in a circuit
parallel = sum of all resistance in a circuit divided by the number of components

    

11Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 8:59 pm

kioolt

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That tells me nothing about how to wire it into the circuit.  I need directions like cut the wire and so forth.


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

12Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:07 pm

tagaz

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LED Indicators 390px-Resistors_in_series.svgSeries






LED Indicators 301px-Resistors_in_parallel.svgParallel

    

13Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:07 pm

robmack

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If you are doing a direct replacement of the incandescent bulbs for LEDs, and still using the same OEM flasher circuitry, then ballast resistors at each signal is not required.  This is a BMW, not a Japanese motorcycle.  Ballast resistors are a stop-gap solution for Far East machines.

The electronics inside the OEM flasher can accommodate the change to LEDs easily. The only alteration you have to make is to disable the hyperflash functionality inside the flasher (blinking the signals at twice their normal rate).  Hyperflashing occurs when the circuit detects a blown signal bulb as evidenced by the reduced current draw.  This change is accomplished by removing the ground on pin 7 of the U243B integrated circuit.  The link I supplied above shows the particular trace to cut.  Cutting the trace will cause the flasher module to not sense the reduced current and try to hyperflash the signal lights.  You signals will function normally again.

You will note that there are two different types of flasher modules for K-bikes. One has through-hole components and a brown circuit card; the other has surface mount components and a green circuit card. Which is yours?



Last edited by robmack on Wed Jun 21, 2017 9:10 pm; edited 1 time in total


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

14Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:10 pm

tagaz

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robmack wrote:If you are doing a direct replacement of the incandescent bulbs for LEDs, and still using the same OEM flasher circuitry, then ballast resistors at each signal is not required.  This is a BMW, not a Japanese motorcycle.  Ballast resistors are a stop-gap solution for Far East machines.

The electronics inside the OEM flasher can accommodate the change to LEDs easily. The only alteration you have to make is to disable the hyperflash functionality inside the flasher (blinking the signals at twice their normal rate).  Hyperflashing occurs when the circuit detects a blown signal bulb as evidenced by the reduced current draw.  This change is accomplished by removing the ground on pin 7 of the U243B integrated circuit.  The link I supplied above shows the particular trace to cut.  Cutting the trace will cause the flasher module to not sense the reduced current and try to hyperflash the signal lights.  You signals will function normally again.
i can't see the link

    

15Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:11 pm

robmack

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__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

16Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:12 pm

kioolt

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robmack,

The OP stated that his bulbs just light up and don't flash.  That is not what the usually complaint is.  Have you ever seen this before?


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

17Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:16 pm

robmack

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Yes, Look at reply #22 and #23 in that thread.

BTW. ballast resistors _may_ be a way to fool the bulb monitoring unit in the K-bike if you don't want to eliminate the BMU altogether.   The BMU monitors the rear running lights and rear brake lights.  The BMU does not monitor the signal lights, luckily.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

18Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:23 pm

kioolt

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robmack,

Isn't the resistance of the LED bulb actually higher then the regular bulb not lower at stated above?  I always though LEDs are suppose to be energy efficient.


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

19Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:34 pm

AndrewP

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tagaz wrote:
robmack wrote:If you are doing a direct replacement of the incandescent bulbs for LEDs, and still using the same OEM flasher circuitry, then ballast resistors at each signal is not required.  This is a BMW, not a Japanese motorcycle.  Ballast resistors are a stop-gap solution for Far East machines.

The electronics inside the OEM flasher can accommodate the change to LEDs easily. The only alteration you have to make is to disable the hyperflash functionality inside the flasher (blinking the signals at twice their normal rate).  Hyperflashing occurs when the circuit detects a blown signal bulb as evidenced by the reduced current draw.  This change is accomplished by removing the ground on pin 7 of the U243B integrated circuit.  The link I supplied above shows the particular trace to cut.  Cutting the trace will cause the flasher module to not sense the reduced current and try to hyperflash the signal lights.  You signals will function normally again.
i can't see the link
Thanks Guys, I will give this a go and let you know what happens  Smile

    

20Back to top Go down   LED Indicators Empty led vs incandescent Wed Jun 21, 2017 9:41 pm

tagaz

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Here's and explanation I copied from an internet resource for my own reference collection. I don't recall the original source.


"An LED (the diode component) is not a resistive device. Once a diode reaches its threshold voltage, it "turns on" and the effective resistance of the device is essentially zero. 

Because of this, LED devices typically have a resistor in series with the diode. When the diode resistance goes to zero, the resistor determines the current in the circuit. This limits the current that flows through the diode to keep the diode from burning out. 

So, what you have in your torch bulb is an LED in series with a 300 ohm resistor. when the LED turns on, its resistance goes to zero, the total resistance is 300 ohms, which limits the current to 10 mA. At 3V, your total power consumption is 30 mW. 

For the amount of light the LED generates, this is still significantly more efficient than an incandescent bulb. (a 10 W LED bulb generates about the same amount of light as a 65 W incandescent, and there's a lot less wasted heat.)"

    

21Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:46 pm

kioolt

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The description for the LED you found is correct.  The problem with applying it to the bulbs sold for use as turn signal bulbs is that the series resistor is already built into the bulb.  The LED description you found is for one that you would go down to radio shack and buy in one of their blister packs and built your own circuit.  The resistance of LEDs turn signal bulbs is actually high because of the built in series resistor.


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

22Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:47 pm

robmack

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kioolt wrote:robmack,

Isn't the resistance of the LED bulb actually higher then the regular bulb not lower at stated above?  I always though LEDs are suppose to be energy efficient.
As Tagaz correctly pointed out, this is not strictly true. because LEDs are active semiconductor components and not simply resistors, like an incandescent bulb.  

LEDs offer low impedance to current flowing in one direction, and high impedance to current flowing in the opposite direction.  A LED lights when the current flows in the forward direction through the device from its anode to its cathode.  The amount of current drawn by a LED is very small ...  about 20mA.  There is a very slight voltage dropped across the LED, about 1.2V - 2.4V, when lit.  It's the low current draw that makes LEDs seem like they are low resistance.  Ohms Law states R = E/I, where I = 0.02A and E = 2.4V.  Therefore R = 120 ohms.  That's low resistance.  

However, if you were to apply 12V across a normal LED, it would blow up. Its 120 Ohm resistance would attempt to draw 12V/120 = 0.1A (100mA).  Therefore you have to have a series resistor to limit current.  The resistance of the LED (120 ohms) plus the series resistance (470 Ohms) makes the combination seem high.

Does that make sense?


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

23Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:50 pm

kioolt

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But isn't the series resistor for turn signal LEDs built into the bulb?


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

24Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:51 pm

robmack

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AndrewP wrote:
Hi Rob,

I did see this but its waaaayyyyyyyy out of my league  Very Happy Very Happy

Andrew

No problems, Andrew. We'll guide you through the process step by step. See whats inside your flasher module first (see my posting above ... through-hole or SMD).


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

25Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:53 pm

robmack

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kioolt wrote:But isn't the series resistor for turn signal LEDs built into the bulb?
Correct, it is.  That's what I confirmed.  If you measured the resistance of a 12V LED sold for automotive use, in one direction it would show infinite ohms and in the other about 500 ohms.

If you have a modern multimeter with a "Diode" setting, the meter will indicate the reverse resistance and the forward voltage drop. Much more useful than a bog standard ohm meter.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

26Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:56 pm

kioolt

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So, the effective operating resistance is higher because the current is lower.


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

27Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 9:56 pm

tagaz

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the only led mods i have done were a few yrs back. 
and those led turn signal bulbs &  tail/stop bulbs had no built in resistors.
i do recall seeing the ones you speak of when i was in town trying to find a bulb for the front park light/eyebrow light.
i may have to give 'em a try.

My training in electronics began when computers ran on valves/tubes.
And one of my favorite rules/laws was "Moore's Law".
Which states, " Technology will double every six months".
Moore's Law became extinct some time ago.
Nowadays it can double at anytime.

    

28Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 10:01 pm

kioolt

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I got my degree in industrial electronics in 1976.  Did you get my PM or did I not complete all the necessary steps to send it?


__________________________________________________
2004 R1150RT 186,800 miles 
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total 422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

29Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 10:11 pm

AndrewP

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robmack wrote:
AndrewP wrote:
Hi Rob,

I did see this but its waaaayyyyyyyy out of my league  Very Happy Very Happy

Andrew

No problems, Andrew.  We'll guide you through the process step by step.  See whats inside your flasher module first (see my posting above  ... through-hole or SMD).
Ok too easy, oil and filter change completed now onto my favourite " electrics " will open up relay and cut to pin 7 and try connecting the LED'S again : )  let you know hoe I go

    

30Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 10:13 pm

tagaz

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kioolt wrote:I got my degree in industrial electronics in 1976.  Did you get my PM or did I not complete all the necessary steps to send it?
pm rcvd & replied

    

31Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 10:14 pm

duck

duck
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Load resistors are a kludge. (And they generate heat which usually isn't a problem but can be if you're unlucky.)

Much easier and better just to cut Pin 7 in the flasher relay.

http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/ledoemflrelay/ledoemflrelay.htm


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT
91 K1
93 K75S (K11 front end)
91 K75S (K1 front end)
14 Yamaha WR250R
98 Taxi Cab K1200RS
14 K1600GT
http://www.ClassicKBikes.com
    

32Back to top Go down   LED Indicators Empty Re: LED Indicators Wed Jun 21, 2017 11:27 pm

AndrewP

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LED Indicators Img_3310
LED Indicators Img_3311
robmack wrote:
AndrewP wrote:
Hi Rob,

I did see this but its waaaayyyyyyyy out of my league  Very Happy Very Happy

Andrew

No problems, Andrew.  We'll guide you through the process step by step.  See whats inside your flasher module first (see my posting above  ... through-hole or SMD).
Ok Flasher relay out and popped off the casing and this is how mine looks Surprised

    

33Back to top Go down   LED Indicators Empty Re: LED Indicators Thu Jun 22, 2017 1:01 am

robmack

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LED Indicators Img_3310

Just cut that small trace between the pin and that large copper island. Don't nick any of the other traces.

In the future, if you want to restore the circuit back to stock, it's an easy fix to solder a small wire across the cut trace, bridging the pin with ground again.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

34Back to top Go down   LED Indicators Empty Re: LED Indicators Thu Jun 22, 2017 1:30 am

AndrewP

AndrewP
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robmack wrote:LED Indicators Img_3310

Just cut that small trace between the pin and that large copper island.  Don't nick any of the other traces.

In the future, if you want to restore the circuit back to stock, it's an easy fix to solder a small wire across the cut trace, bridging the pin with ground again.

YOU ARE A LEGEND !! cheers cheers cheers Worked a treat    Big thumb

    

35Back to top Go down   LED Indicators Empty Re: LED Indicators Fri Jun 23, 2017 8:16 am

robmack

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Glad to hear it worked. Enjoy!


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

36Back to top Go down   LED Indicators Empty Re: LED Indicators Mon Jul 03, 2017 2:51 pm

SniperX

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kioolt wrote:That tells me nothing about how to wire it into the circuit.  I need directions like cut the wire and so forth.
Just wire the resistor in line with the hot going to each lamp individually.


__________________________________________________
1985 BMW K100RT, 2006 Ducati ST3, 1996 Honda CBR1000f, 2001 Honda XR400r
    

37Back to top Go down   LED Indicators Empty Re: LED Indicators Tue Apr 09, 2019 1:47 pm

Martcarl

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Hello! I was having the same issue with my led blinkers as described of most of you in this thread. So I followed your advice to “cut a leg” on the microprocessor and now it works perfect! Thank you!

The thing is that when I opened the relay box I unfortunately hit one of the condensators on the card so bad it fell off. See picture.

The blinker function still works perfect so now I wonder what the condensatior is for and if I need to repair it.

Best regards
Martin

https://i.servimg.com/u/f80/20/05/64/87/ed61ca10.jpg

    

38Back to top Go down   LED Indicators Empty Re: LED Indicators Tue Apr 09, 2019 1:49 pm

Martcarl

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Conductor may be the right word for the component. 😁

    

39Back to top Go down   LED Indicators Empty Re: LED Indicators Tue Apr 09, 2019 11:50 pm

charlie99

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VIP
VIP
likely means capacitor

in some cases the capacitor function is just to smooth the power ( Positive supply ) going to some components


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
1987 k100rs ########   "Red"  - (red sports rs TWB style )
1989 K100rt #009637   "Black Betty"  (naked rt ala Nigel , now sporting an rs main fairing )
    

40Back to top Go down   LED Indicators Empty Re: LED Indicators Fri Sep 16, 2022 9:42 pm

Clintinz

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Thanks for the wealth of knowledge. This has been great and to find and I’m about to proceed with the cut. However I found a point that looks burnt out. Does anyone know what this is And whether I should solder it up before I pack it up? The bike was working when I took it apart but don’t want to miss anything while I’m putting it back together. CheersLED Indicators 2aa74c10
LED Indicators A542ed10

    

41Back to top Go down   LED Indicators Empty Re: LED Indicators Fri Sep 16, 2022 11:53 pm

robmack

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Looks like at some pint in the bike's life there was a short in the dash wiring.  Excess current was drawn through the relay contacts and burnt the PCB which couldn't handle the current.  The board appears to have been reworked at some point also.  There is burnt flux around many of the contacts towards the edge of the card.  I'd first clean up the board using isopropyl alcohol and a brush.  Then once clean, resolver the relay contact. Check that none of the traces are burnt through.  Then you can probably put the module back in service.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

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