LED Indicators - Flash Rate

Anyone know what resistance I need to run in parallel with an LED indicator to make it falsh correctly. I calcalated with a 21W bulb, it would draw 1.75A so, assuming the LEDs draw is negligable, I would need a 7 ohm resistor in parallel - does that sound right?

Thanks

Yes, thats what I worked it out to be, although 8 ohm is about as close as you will probable get which should be OK. As the power is only on for half the time you could go down as low as 10W in power. Could use the 21W bulbs tucked away somewhere or covered up instead.

[Spiderman]

Errr translate that to a language i understand and witout the maths and i'll happily answer your question

Alternatively...

I have LED cators front and back. The number of other bikers, including couriers, who have chased me and asked where they are from and how i got them flashing so fast convinced me its a good thing.
The faster flash i mean.

I've been told reliably that a flash rate of 90-120 per min is acceptable under MOT regs.

I had an MOT done recently and asked ahead if they were bothered that my LEDs flashed fast. No they didnt give a damn as long as they flashed at the same time and within the limits.

If london bike couriers notice my cators then i have some hope that a few cagers will too.

hth

if it bright and flash fast i would not have a prob but if you can not really c them and flash fast i seen a few then na that stupid

look good but a bit slower is better IMO