H4 bulbs can I swap for an LED bulb

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Daddy Dom
Posts: 512
Joined: 16 Nov 2006 19:48
Location: Auckland, New Zealand

Re: H4 bulbs can I swap for an LED bulb

Post by Daddy Dom »

Wow, quite a difference. I'd be curious to see the pattern it makes on the road, too, if you wouldn't mind?
Jolly good! :lol:
MRC 3082½
Fastmongrel
Posts: 208
Joined: 07 Nov 2022 22:37
Location: Lancashire

Re: H4 bulbs can I swap for an LED bulb

Post by Fastmongrel »

Haven't had a chance to do a night ride yet but weather looks good for Saturday and Sunday night.
1981 3 1/2 Strada
Fastmongrel
Posts: 208
Joined: 07 Nov 2022 22:37
Location: Lancashire

Re: H4 bulbs can I swap for an LED bulb

Post by Fastmongrel »

Well I tried the led bulb out and it's going in the bin

Dip is fine
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Main beam is bloody awful
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In fact it's lethal I turned down an unlit country road flicked main beam on and I couldn't see a thing just glare. It throws further on dip all main does is light up the sides and road. Wish I hadn't wasted £36.
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Third photo is same viewpoint as first it doesn't come across how much glare there is but you can see it doesn't go very far
1981 3 1/2 Strada
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Daddy Dom
Posts: 512
Joined: 16 Nov 2006 19:48
Location: Auckland, New Zealand

Re: H4 bulbs can I swap for an LED bulb

Post by Daddy Dom »

Wow, thank you so much for organizing that.
So even if you tilted the headlight up for main beam, your dip would be way too high, would it?

Cheers, DD
MRC 3082½
Fastmongrel
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Joined: 07 Nov 2022 22:37
Location: Lancashire

Re: H4 bulbs can I swap for an LED bulb

Post by Fastmongrel »

Yes I would be dazzling other road users. I am going to have a chat with the seller Paul Goff it might be that my rectangular headlight isn't suitable for an Led bulb or I have cocked up fitting it.

It was scary doing about 40mph on a road that I fortunately knew well and suddenly I couldn't see a damn thing apart from glare and the hedge either side of me. There's nothing wrong with LEDs I have a light on my pushbike that is brilliant but it's not the power it's about the way the light is reflected.

I might look for a nice round headlight with a reflector designed for LEDs.
1981 3 1/2 Strada
Fastmongrel
Posts: 208
Joined: 07 Nov 2022 22:37
Location: Lancashire

Re: H4 bulbs can I swap for an LED bulb

Post by Fastmongrel »

Just noticed the rev counter illumination bulb has fallen out again I am going to glue the damn thing in place.
1981 3 1/2 Strada
morini_tom
Posts: 928
Joined: 05 May 2006 13:47
Location: Northampton

Re: H4 bulbs can I swap for an LED bulb

Post by morini_tom »

I didn’t get on at all well with the P43t daylighter LED in my sport (same square headlight as you) and instead swapped it for a Hella HR2 60/55W halogen bulb.

The halogen HR2 is very good with a more correct beam pattern and is the correct type of fitting for the reflector. Ok not the power saving I was after but my alternator in good condition and with a decent AGM battery means I’ve never had any problem even with several hours riding in the dark and using the electric start.

For decent daylight visibility I’ve tended to use a more Helly LED pilot bulb which gives a good brightness and some colour which helps to stand out from the queues of cars with white daytime running Lights.
Fastmongrel
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Joined: 07 Nov 2022 22:37
Location: Lancashire

Re: H4 bulbs can I swap for an LED bulb

Post by Fastmongrel »

The original bulb was a P43 but I have an adapter for a H4 bulb I wonder if that's thrown the bulb out of alignment. I have refitted the halogen bulb and noticed the bulb glass is a bit cloudy. Possibly that's why it was so wimpy I will try a new H4 halogen when shops open.
1981 3 1/2 Strada
Steve Brown
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Joined: 12 Nov 2007 23:44
Location: Leicestershire

Re: H4 bulbs can I swap for an LED bulb

Post by Steve Brown »

That's a surprise and obviously a disappointment too. Mine is really rather good but in a round headlamp without any adaptor bits needed.
Tom, if you are retiring your daylighter I'd be happy to try it in my bikes, in the interests of research obvs. I can try in the Camel rectangular lamp and various round headlamp types.
All donations to the rest home for old Camels, Leicestershire.
3potjohn
Posts: 1246
Joined: 02 Jun 2007 13:58
Location: Devon

Re: H4 bulbs can I swap for an LED bulb

Post by 3potjohn »

I have had instrument bulb holders drop out when hitting a pothole so not unusual. Pity about that light pattern. My concave Cibie is fine, or it was last time I rode a distance in the dark. Another bike has twin 35W bulbs. Seems a bit pathetic too . I did not update to LED on that bike because it’s my understanding it can fail MOT being a ‘89 model.
I use a LED pilot but this has a slightly blue tint.
MickeyMoto
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Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: H4 bulbs can I swap for an LED bulb

Post by MickeyMoto »

I think it may be due to the unsuitability of the reflector and the glass. The same problem occurred when using a halogen bulb in a tungsten bulb designed headlight.

Try looking for a complete LED unit, the problem then is the spaghetti in the shell.
3potjohn
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Location: Devon

Re: H4 bulbs can I swap for an LED bulb

Post by 3potjohn »

Keep up John! Reading the latest MOT guidance the year of manufacture limit for the motorcycle ( converted to LED) has been removed. The light pattern must pass of course.
Fastmongrel
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Joined: 07 Nov 2022 22:37
Location: Lancashire

Re: H4 bulbs can I swap for an LED bulb

Post by Fastmongrel »

I will have a look at a complete LED unit the rectangular headlight even with a halogen bulb in it is poor. I guess it was designed for a tungsten bulb.
1981 3 1/2 Strada
Fastmongrel
Posts: 208
Joined: 07 Nov 2022 22:37
Location: Lancashire

Re: H4 bulbs can I swap for an LED bulb

Post by Fastmongrel »

I had a look at LED light units but they all look horrible to me like something designed by a ten year old. I bought a cheap chrome headlight off fleabay and fitted the LED bulb I bought from Paul Goff. I haven't done a test ride because rain stopped play but a quick comparison using the end of the shed shows a lot less scatter from the new round unit, also looks better than the rectangular headlight it looks a lot like a Lucas unit.
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1981 3 1/2 Strada
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