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Author Topic: JDM vs UJM Manual??  (Read 270 times)

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Offline Dr. Frankenstein

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JDM vs UJM Manual??
« on: August 22, 2025, 07:06:54 PM »
I have a 1973 CB500 Four JDM (Japanese Domestic Market) that I'm thinking about making my next project, but I'm wondering about the electrics. This bike has a light in the steering stem, and I'm wondering if there's a wiring diagram or different manual for this bike, or is it just like the 'regular' CB500's? How does that light work?
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Offline pickleknuckles

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Re: JDM vs UJM Manual??
« Reply #1 on: August 22, 2025, 07:14:05 PM »
Quote from: Dr. Frankenstein on August 22, 2025, 07:06:54 PM
I have a 1973 CB500 Four JDM (Japanese Domestic Market) that I'm thinking about making my next project, but I'm wondering about the electrics. This bike has a light in the steering stem, and I'm wondering if there's a wiring diagram or different manual for this bike, or is it just like the 'regular' CB500's? How does that light work?
Not sure how it actually works but it flashes when exceeding a set speed.

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Offline HondaMan

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Re: JDM vs UJM Manual??
« Reply #2 on: August 22, 2025, 07:42:20 PM »
Yeah, what PickleKnuckles said: I think they come on at about 50 MPH (whatever kM/hr that is?).
The majority of the wiring is the same as the General Export models.
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Offline scottly

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Re: JDM vs UJM Manual??
« Reply #3 on: August 22, 2025, 08:22:57 PM »
I think the sender for the speed light is inline with the speedo cable?
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Online PeWe

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Re: JDM vs UJM Manual??
« Reply #4 on: August 22, 2025, 09:46:36 PM »
Quote from: HondaMan on August 22, 2025, 07:42:20 PM
Yeah, what PickleKnuckles said: I think they come on at about 50 MPH (whatever kM/hr that is?).
The majority of the wiring is the same as the General Export models.
The easy way: Mph x 1.6 = Kph
(1.609344)
50mph = 80kmh
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Offline lash

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Re: JDM vs UJM Manual??
« Reply #5 on: August 23, 2025, 02:20:10 AM »
I reasearched that with Marcel when he restored some gauges for me. it is an overspeed light designed to come on at 80 kph. It is energized by a special speedometer connection and you cant just add one to a normal speedo, has to be built for that. Marcel had one for my 750 but it was large cash. I ennded up putting a red light n te hole and hooking it up to the oil pressure light,
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Offline bryanj

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Re: JDM vs UJM Manual??
« Reply #6 on: August 23, 2025, 03:54:43 AM »
The actuator is in the speedo with a "box" mounted by the coils and the light in the stem nut.

There is an early 500 JDM parts book in Ash's dropbox on the UK forum, i know as it was mine! Only place i found a pic and part number for the small transfer under the sidepanel badgethat says Honda Motor Co Tokyo Japan.

The JDM had fixed footrests as well
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Offline Dr. Frankenstein

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Re: JDM vs UJM Manual??
« Reply #7 on: August 23, 2025, 04:55:43 AM »
Thanks for all the info guys; Bryan do you have a link to that JDM parts list? It might come in handy, thanks.

Here's a few more pics of the interesting bits; anybody speak Japanese...? Near as I can figure, I think this was probably bought by an American GI and shipped home. The points look okay...the only problem right off the bat is the engine is stuck, but no biggie there, I just rebuilt two of these inline fours.
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Offline pickleknuckles

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Re: JDM vs UJM Manual??
« Reply #8 on: August 23, 2025, 06:00:38 AM »


Quote from: Dr. Frankenstein on August 23, 2025, 04:55:43 AM
anybody speak Japanese...?

Courtesy of Google Lens.

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Offline CycleRanger

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Re: JDM vs UJM Manual??
« Reply #9 on: August 23, 2025, 06:01:16 AM »
As to that round sticker see my reply in this thread.  :)
http://forums.sohc4.net/index.php/topic,195925.msg2301674.html#msg2301674
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Offline Dr. Frankenstein

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Re: JDM vs UJM Manual??
« Reply #10 on: August 23, 2025, 06:45:10 AM »
Oh yeah! I forgot about that, thanks!  :D
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Offline bryanj

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Re: JDM vs UJM Manual??
« Reply #11 on: August 23, 2025, 09:05:53 AM »
Sorry too old to understand links, go to sohc.co.uk and on top line look in Ash's dropbox and you will find lots of things to download
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Offline Deltarider

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Re: JDM vs UJM Manual??
« Reply #12 on: August 25, 2025, 01:48:03 PM »
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