Headlight restoration : does it work ?

so over the years headlights have gone from glass lenses to plastic lenses and as you may have seen with your own lenses they can turn yellow or have a foggy white look to them over the years as the UV coating wears away from traffic dust and all that road salt and likes kicked up.
BUT the cost of replacing your whole headlight can run into the £100 mark, or you could by a second hand unit and find that two has some old age fogging and/or yellowing. so what can be done to bring that lenses back to its prime ? and is it possible ?

So over the years i have heard a lot of ways to bring life back to a headlamp lenses. most cost around £30 - £50 and require you to sand the headlamp with sand paper then use a cutting and buffing compound on a drill to polish it. that is a lot of work for us bike owners and even a car owner and you could do things incorrectly and screw up the final finish costing you even more money, not good if you spent upwards of £50 hard ones and then find you have to fork out around £100 for a new light. so is there a more simple method we could use, and it works out there are several ways. but i will use the cheapest @ £1.49p and some elbow grease with some good old tap water.

now three methods , one is the sand and polish its the most expensive and time consuming.
second is a mixture of white vinegar and baking soda (bicarb of soda in the uk) . and the third way is good old TOOTHPASTE and a rag or tooth brush, thats the method i will be trying out to see if the myth realy works and how well.
i have been out and grabbed some good old original turtle wax and a tube of ArmandHammer toothpaste with baking soda added , the wax is going to help seal my polished headlight until i can clear coat it to give a fully protected seal, but for quickness the wax should protect it for a few days/weeks/months. now you could use normal tooth paste but baking soda is a rough like compound and will be more abrasive than just plain toothpaste so is a better choice , and hence why i went with toothpaste with added baking soda. ( see image attached )

Stay tuned for tomorrows update when i prep the headlamp on my sym jet 2006 model and show you the Before toothpaste - midway tooth pasting and the final finish after toothpasting and washing it all off pictures and we will see if this Myth really works and if it will make those old fogged headlamps sparkle nice and clear and banish that foggy and yellowed look for good. , hey we may even find they smell great to lol.

 

Well this morning i spent 24 mins on the lenses ( the left one) with the toothpaste and circular rubbing motion using a decent cloth, about four applications of toothpaste to stop it being a dry rub in. and well the results ........

To be honest i cannot tell a difference between the before and after images i snapped, they both look the same , so myth is busted it did NOT work for me but maybe you have to spend like three hours rubbing those lenses to get anything like they show on the interweb. But one good thing came out of it, my scooter has this awesome minty fresh smell to it LOL , well only until i fire up the twostroke motor then its gonna smell like it should do lol

judge for yourselves ( Before image has birdy poop on the front fender - after image has no birdy poop)

 

So after putting on my reading glasses , I can see a difference in the light unit. the before does have a yellow tinge to it where as the after has a more clear less yellow look.
if you look into the bottom of the left reflector you can see vertical lines running towards the bulb, they are some what not very well defined in the before image, but the after image you can clearly see those lines being more pronounced.

my conclusion is 24 mins on each lens is a bit low and they would need a second treatment toothpaste to fully cut away the remainder of the factory UV coating. another point is the light lenses get attacked from both inside and outside, you have the sun shining on those lenses from the outside, but night time running you also have that bulb outputting UV light to so the plastic is attacked from both angles, being plastic sealed units your unable to treat the inside of the lenses to get the maximum benefit, but it does look like it has worked some what.

time will tell once it gets dark, i will head out to my local super dark country lanes and see if it has had an impact on the light being thrown to the road, the one downside is i am unable to install the new halogen bulb i sourced as i think its going to melt the low grade plastic bulb fitting and possible the headlamp itself being made from plastic.

So yes there is a change, if its some what not crystal clear it has made some sort of impact on the yellowing tinge in the before image.

UPDATE :

the proof is in the pudding and the only way to really see if there was a change is a night time ride down a couple of country lanes.

to start of with , LOWBEAM , is slightly brighter with a bit of a better colour. instead of the very orange hue light cast, its now a more subtle orange hue. view distance is roughly the same and lamp coverage to , your still wondering whats coming up but less aphrehensive to swish the brakes and bring the speed down to a crawl. i felt comfy at 25mph than at 35mph the slower speed gave me more of a reaction time. behind cars at lights you could tell they were brighter the reflection from the rear of cars was more seen as a headlamp and not a candle like dim glimmer.

HIGHBEAM, Now the roads i travel i know very very well , every turn bump camber and kink, these are single file roads with plenty of passing points to. with high beam i had noticed a better spread of light and slightly more distance speed was upped to 40mph-45mph and i felt very comfy ( but i know these roads so well ) , the speed limits on the road was 70mph , and all felt good a little slippy with the gravel edging but all ok. light throw was better than before headlight was toothpasted and wax buffed. colour was the same but cast more even and you could tell there was a change. less yellow orange more a tint hue orange ( bulb is a BA20D stock not a halogen).

One area to look at would be a bulb upgrade, i think then the headlamp would really show up well but alas plastic and high temp bulbs do not mix well and i am afraid of melting the sym jet basix headlamp / bulb holder. so it either needs a cold air ducting mod or some well drilled holes. but either method is going to open the light upto the elements and possible water ingress. i am yet to find a UK legal LED bulb but when i do it will be thrown in for testing.

so yeah it worked but you need to spend more time and really hone that UV coating off to remove all the yellowing and then give it a decent UV protected clear coat for maximum protection and a few more years yellow hue free.