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was thinking about fiting LED bulbs but been told will need a new relay. anybody tried this ?

just replace the rear stop/tail and don't think you need to change the relay.

They just swap straight in. Don't need to change anything.

Didn't know they did indicator LED's or are you not woried about the correct wattage for the bulbs, i know a LED is rated different but legaly a indicator should be rated 21W's i'm not sure how this rates on a LED.

yes you can buy indicator LED's. i almost bought some but there VERY expensive and i couldn't see that they warranted the cost. just put LED bulbs in place of your tail and brake light. and remember that they only work one way round too.

Just looking through the SIP web site and came across a LED indicator relay, says something like " having problems with your LED bulbs not blinking or blinking fast then this will sort it out" so maybe you do need the relay.

You need specific relays for indicators, for sure.
Regular light bulbs take longer to ignite, light up, and become totally extinct again, than LEDs, which turn on/off almost instantly. That's fine for non-flashing lights such as tail/stop lights, but the originally set timing for indicator bulbs will be totally off, or not work altogether when LEDs are fitted. The relays then serve to change the timing so it matches the normal on/off lapses. The only case when you don't need relays for normal operation, is when your bike's wiring has been engineered to operate LED indicators as standard.
One thing though, is that relays get extremely hot, so they should not be confined, set against rubber/plastic/melting materials in general, or next to the gas tank or near any flammable fumes. The relays need to be paired up with each LED cluster, so you'll have to think out in advance where you'll be positioning these 4 extremely hot devices.
That being said, I followed a guy on a jap sportsbike once through Paris rush hour traffic, and found the clean, sharp blinking of the indicators was a very effective eye-catcher. Very useful when passing car drivers, who give a backseat to other road users while babbling on the cell phone, and/or watching the TV, ...er, GPS screen as they "drive".

Had led's on my sportsbike and water had got into the circuits board at the back and caused all mayhem for over 2 hrs setting of my alarm every couple of minutes had to rip the led indicators out and stick in plain one's. As koolchris said they are very catchy and tin-can driver pay more notice.

I'm unsure on these still. In electronics, LEDs are diodes and therefore work only on DC. yet the P range has an interesting system which it runs on 12v AC. In electronics you cannot use LEDs successfully on AC circuits, they need to be rectified to DC. I haven't looked into the wiring of later P range scoots with batteries as they may be completely DC but you need to be careful with these things.
If you know otherwise then please correct me as I'd like to try LED stop and tail lights on my mk1 T5.

firstly... you only need one relay to operate all 4 indicators. As stated, you will need one with a different time lapse as there are quite strictly defined limits on what passes as an indicator flash time. Flickering is definately outside them. Just swap out your old relay for the new one and jobs done.

Secondly, DJSwampy... in theory thats correct, an LED is a one way only bulb and is designed to work with a DC system but if you think about it an AC system is only DC system that reverses polarity at a rate related to (in this case) the engine speed of the scooter and so is correct for the diode exactly half the time. In theory this should stop them working, but it doesn't. Plenty of scooters are running AC systems with LEDs now as proof.
If you wanted to do the job properly then you would need a rectifier wiring in line to the AC line after the stock one, or rewire the scooter from scratch using a different rectifier unit.
I suppose you could rectify each circuit individually instead, but I'm not sure it would be worth the hassle.

indeed, my thoughts were though that the frequency of on/offs, could cause damage to the unit. I wasn't sure and when I spoke to electronics people they just went for the old suggestion of stick a rectifier in which wasn't much use.
I have a few jobs on the T5 and I think I might try a LED rear light pair. Its good to know that others have tried and worked successfully.