Motolamp

[motor-officer]

Motolamp's use the 3-hole twist and lock headlight bulb. Is there a specific name for the base of these type bulbs?
Secondly, I have a Motolamp style bulb holder that mounts to the reflector. The two pins are 180 degrees different than my others. Were early Motolamp bulb holders different?

[RonH]

P15D-30 is the base number, This one?

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[JTR249]

I have a 1942 that looks very different in several ways. There could have been a change between '42 and '49-'53.
However, I have only noticed the difference on the internal parts, not the bucket, bezel or glass.
People once told me, the '49-'52 Indian Vertical bezel has different mounted screw fitting at the join.
I don't know anything about the bulb base names.
Can't locate my photo right now. If you need a comparison, I'll see if I can post tomorrow.
-JR

[pisten-bully]

...this is from https://www.classicandvintagebulbs.com , a really good online source for bulbs :

IMG_4164.jpeg

[Steve Slocombe]

The early Motolamps, say 1930-39 used a regular straight two pin bulb holder. Harley went to the three point fixing in 1935 with the change to the Cycleray headlamp, but I don't know the equivalent Indian date.

[PaulCDF]

I call them "Pre-focus" bulbs only because that is the term used by a seller I them from.



Headlight A.JPG


Headlight C.JPG



Headlight B.JPG

[otis71]

I bought a box of 3 pin bulbs at Hersey and when installed the contacts are 90 degrees off from the original Cycleray socket. Never did find information on different ones.