LED/Low wattage indicator flasher rate fix--sorta

[FelixLeiter]

Whilst performing my fender elimination I sorted out the flashing rate on my signals…

I installed Rizoma bullet signals on the front (5W each) and LED flashers on the rear (<1W each) where the bracket for the reflectors were mounted. I have tried several new flasher relays to no avail…still a flash rate of about 180/min.

So I had the brainstorm to install an integrator unit on the brakelamps ($22 Cda for a “Reese” universal trailer light controller). My idea was that the brake lights are 20W each, which will make up enough resistance to normalize the blinking rate of the signals (as the original signals are 10W x 2). Well, it works! Unfortunately it works when ONLY the indicators are on; as soon as you engage the brakes (and hence the brake light) the flasher rate goes from about 60 to 120 per minute. There must be a relay built into the integrator unit to allow one light to blink when the brake lights are on. This would remove the 20W load of the flashing brake light from the ‘system’ and the existing flasher relay on the bike only “sees” the lower wattage indicators…causing the rate to speed up.

RIZOMA SIDE:


RIZOMA FRONT:


LED SIDE:


LED REAR:

[Martin_R]

Wire 1 resistor per LED indicator parallel with the LED indicator (see http://www.ledtronics.com/ds/aut1157m/ for example). That should cure everything and make the rear blinkers appear the same as the front from the relay's point of view.

So if one stock indicator was 21W and the Rizoma is R W, then the load on the relay per side was 42W and:

(42W - R W - LED W) / 12V = Y amps
12V / Y amps = X ohms

The X is the size of the resistor you need to have with one LED blinker in order to have the equal amount of resistance on one side of the relay as there was with the stock bulbs. I would get the kind with the heatsink and mount them attached to the frame as they will get hot.

I did not quite follow your point about adding the integrator to further complicate things. I am sure Rizoma W+integrator W+LED indicator W is still not the same as original 21+21W. You still have only two LED devices replacing one bulb and as a LED blinker usually is 1-2W you are still 17-19W short per side? No?

[ This message was edited by: Martin_R on 2006-04-27 14:31 ]

[Martin_R]

.

[ This message was edited by: Martin_R on 2006-04-27 14:12 ]

[FelixLeiter]

Resistors heat up too much. When I was only running aftermarket indicators in the rear (stockers in the front) I wired a 10W resistor parallel to the aftermarket indicator. The thing heated up to the point of being too hot to pinch between my fingers within 10 seconds.

The problem with the blink rates is that the blinker relay is rated at 10W x 2: meaning that 2 signal lights with a bulb rating of 10W will be working at the same time when indicating. This gives a total system load of 20W. Reducing this system load below 20W (Ie. replacing one of the signals with an LED of 1W) will make the relay 'think' that one of the bulbs is burnt out. The relay will then blink much faster than normal, to indicate to the operator that a bulb is out. What one actually needs is a relay that has a variable load rating--one that will blink at the same rate regardless of load. These are hard to find, I found one from an LED mail order place in the states for $15 or so, but the company had a minimum $25 order and then shipping costs. Would have likely been $50 canadian before I was done.

Their are 2 bulbs in the tail/brake light and each is rated at 20W for the brake portion (5W for the tail portion of the 1157 bulb). Therefore, one brake light blinking gives a load of 20W to the flasher relay...allowing it to blink at the normal rate. With my LED (1W) and Rizoma bullet (5W incandescent) I am putting about 26W load through the relay---same flash rate as with a 2x10W=20W load. Flasher relays are set up to blink faster when there is less load, not slower when there is more.