How central must front lamp be?

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SA_SA_SA
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Joined: 31 Oct 2009, 1:46pm

Re: How central must front lamp be?

Post by SA_SA_SA »

Twin headlight motorbikes have one headlamp to the left of centre:

does that have to be the main beam or is a near central dipped lamp viewed as close enough legally?
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IanW
Posts: 176
Joined: 9 Aug 2013, 2:10pm

Re: How central must front lamp be?

Post by IanW »

SA_SA_SA wrote:Twin headlight motorbikes have one headlamp to the left of centre:

does that have to be the main beam or is a near central dipped lamp viewed as close enough legally?


On motorcycles with *1* headlight that has dual high/main *and* low/dip beam, as far as I am aware it is always on the centre line.

On motorcycles with *2* laterally spaced headlights, it is often the case that the near-side (left side in the UK) serves as the low/dip beam
which then *sometimes* stays on when the off-side headlight high/main beam is lit and sometimes does not.

On motorcycles with *4* headlights the lower pair of headlights are typically the low/dip beam
while the upper pair of headlights is used as the high/main beam.

The problem with the latter *4* headlights on modern motorcycles is that on low/dip beam where the two lower headlights are both lit
whilst the beam is indeed *lowered* and has a cut-off at the horizon, they do not necessarily also dip toward the near-side.

This means that while going round a left-hand bend (in the UK) the right-hand low/dip beam actually shines up into the on-coming driver's eyes as the bike leans to the left round the corner.

This is particularly unfortunate on motorcycles that have low/dip beam daytime running lights for which there is no "off" switch.
(I used to get flashed lots for having just these low/dip headlights on.)

I only dared run the OEM bulbs in the low/dip beam headlights
But happily ran the enhanced brightness bulbs in the high/main beam.

When a driver was really insistant that I "dip" my already dipped low beam lights by flashing me lots
I would give them a very brief flash back of all 4 beams.
SA_SA_SA
Posts: 2360
Joined: 31 Oct 2009, 1:46pm

Re: How central must front lamp be?

Post by SA_SA_SA »

So do motorcycles have a special dispensation to have their dipped lamp to the left of the bikes centre line?
Or fairly centrally mounted good enough to satisfy "the law"?
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Colin_P
Posts: 164
Joined: 19 Aug 2013, 2:21am

Re: How central must front lamp be?

Post by Colin_P »

I've still got a bike with a brazed on lug for a lamp bracket on the right hand fork. It was where you put your Ever ready light. I think they had it right.
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Mick F
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Joined: 7 Jan 2007, 11:24am
Location: Tamar Valley, Cornwall

Re: How central must front lamp be?

Post by Mick F »

SA_SA_SA wrote:So do motorcycles have a special dispensation to have their dipped lamp to the left of the bikes centre line?
I doubt they have special dispensation, more likely the law is ignored.

No doubt the manufacturers produce them like that no matter which country they are exported to.
Mick F. Cornwall
ianpallen
Posts: 70
Joined: 12 Nov 2014, 10:43am

Re: How central must front lamp be?

Post by ianpallen »

When I had bikes in the 70's, the lights were mainly eveready lamps and were on the crown mounted light holder, centre of the bike. Racers had them on the right fork as the handlebar sten made it more difficult to put a light on the centre bracket. Around the 80's, eveready brought out the plastic lamps that when stood on a table, the lens was pointing upwards at about 45 degrees. The brackets could be mounted on the handlebar or handlebar stem. The rear light bracket went on the off side (right) seat stay. The affordable or cheap lights today, mostly led's are ones to be seen and not very good at seeing (lighting up) the road ahead. I have an led torch which is also a front bike light but it does not light the way very good. It is good for close up but not distance.
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Cunobelin
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Joined: 6 Feb 2007, 7:22pm

Re: How central must front lamp be?

Post by Cunobelin »

beardy wrote:If you think back to the reason for having this condition, it doesnt matter how far you are from the centre line, it matters how far your light is from the right handside of the bike.
Then if it isnt central it has the possibility of being shielded by the bike itself, if say positioned on the left hand fork.

A similar rule to that imposed on cars may make sense "No further than Xcm from the right handside of the vehicle" Though motorcycles are normally much wider than cycles and can also have only the central light fitted.

The rule was probably established with a recognition that there are only so many good places to mount a light on a bike, and written to prevent us sticking them on the wrong side.
I for one always mount my light just left of centre, I find it more natural with the buttons and dont see anybody interpreting the law so strictly that it is no longer considered central.



I ride a Christiania trike, the box obscures the lights so I have a pair, one each side of the box

Handlebars would in this case be to high for the regulations
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