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electrical

  1. P

    I've been set up!

    Alright, I bought this bike last year, it's a '78 cb750k. The previous owner was planning on having it be a cafe racer style bike. He was almost done, but encountered an "electrical problem" he told me. It did not run when I bought it. I spent that summer and winter tinkering, fixing, cleaning...
  2. Cbguy

    Turn signals kill bike

    Hello out there, I have a 71 cb750 that has run seamlessly for years. I have been riding without issue for the last 2 months since the weather has gotten nice. I had just started my ride home and signaled my turn and the bike died instantly. I was able to start the bike right back up and ride...
  3. K

    30 amp fuse pops when key turned “on”

    Hi all, The problem started after the bike was dropped. Now the main 30 amp fuse pops whenever the key is turned to the “on” position. I replaced the wiring harness and managed to get the bike to turn over a couple times before the main fuse popped again. My battery cables don’t seem to be...
  4. N

    No spark on 2-3, getting power from yellow wire until hooked up to coil

    Hey guys, this is a 1978 cb750k. I am getting spark on 1 and 4, but not 2 and 3. I am getting power in the yellow wire all the way up to the connection to the coil. The multimeter reads that it is getting power, then as soon as I plug it up to the wire that connects the coil it drops off. It has...
  5. S

    Fuel level sensor

    I have a beautiful 1982 CB 750 SCA Nighthawk. Need the fuel level sensor for the tank (fuel gauge device). Any sources for it? Also the Nighthawk emblems off the side covers. Please help! It’s a true time capsule found in a storage locker, wanna do it right. Needs the proper color to be correct too
  6. S

    Pulse generator wire connecter has gunk in it and how to check it

    1982 cb750c custom I’m trying to check the resistance of the pulse gen at the connecter site and a there is some grease in here is this normal? And b I don’t know which wires to be checking together and for what measurement? Any help is appreciated.
  7. K

    Regulator / Pickup Issue / Question

    So working on getting this 78 cb750a up and running. Had it running with the choke on. Then went to test some loose wires with my multimeter trying to find where the solenoid on the carbs plug into on the harness (solenoid plugs cut off). So looking through the repair manual the color...
  8. Tink

    M-UNIT BLUE

    Has anyone fitted an M-unit to their CB750. I inherited a real mess of a wiring system when I bought a project bike (1982 CB750) from a kid that ran out of steam/skill when building a café racer. I'm left with just the electricals to sort out - but a lot of wiring has been replaced (using all...
  9. J

    81 cb750c Starting issues

    Hello everyone, I have an 81 CB750c that’s sat for about a year, before storage she started up just fine. The bike will want to turn over with no key in ignition and kill switch off. I’m hoping it’s just a short in the starter relay solenoid and or a dead kill switch. Where do I start...
  10. S

    Battery cables cb750rc04 '82

    Can anyone tell me what size the battery connection cables should be? The black one going to the frame (ground) is there but the RED one going from the starter main fuse box is fully missing. I need to replace it with a likewise size but have no idea how much the starters from the CB750 rc04...
  11. G

    HondaMan's transistorized ignition

    http://sohc4shop.com/catalog/product_info.php?cPath=23&products_id=32 Does anyone know if HondaMan's transistorized ignition is still available?
  12. R

    OKI MPS-200 replacement

    Hiya all, first of all, sorry for asking a question related to a CB650, not 750 - but as far as I understand, it's the same ignition, so I hope it's okay for this one. So, I'm currently restoring that bike, and I've encountered the "runny potty" problem of the igniters. While there are...
  13. M

    Recomendation for RC04 CB750FD None Resister Plug Caps

    Hi all, I have both NGK resister plugs (5k) and plug caps (5k) and this looks like too much on the spark as I have to set a small gap. I want to drop one of the resisters on each plug but do not want to replace my iridium plugs so looking for a set of recommended plug caps for this model...
  14. D

    1972 Honda CB750

    I have a 1972 Honda CB750. Had it for about 6 years. Never changed the battery, and the bike has always run well and is well maintained. I never let the bike sit longer than two weeks, and if I do, I keep it on a tender. It has a Yuasa AGM battery in it now. Over the past several days, Ive...
  15. S

    1974 CB750k - Carburetors adjustment/balancing

    I’ve watched five or six YouTube videos on balancing carburetors for a CB750. I purchased some balancing gauges from Amazon (set of 4 gauges). “You have to learn somehow”. It seems to be straightforward with using the adjustment screw to balance each carburetor. Is this going to be a big...
  16. S

    1974 CB750k - electric ignition

    Does anyone know if I can put an electric ignition on my bike ? Does someone make one ? If so, How hard is it to install ?
  17. L

    75 CB750 Headlight Switch

    The small plastic switch which turns the headlight off/on has disintegrated. The switch works fine. Anyone know to just replace the plastic piece? Thanks!
  18. Bmb2492

    Will a weak stator ruin a battery?

    82 750 nighthawk with 4,500 miles on it. It hasn't been tagged since 03. I've put 2 batteries on it. One just kept going dead. I checked the rotor and it's sitting on 5.2 ohms. The stator tested fine but they both looked rusty. I cleaned them up. I've only rode this bike 10 miles since I got it...
  19. Bmb2492

    Fuses popping at solenoid

    82 cb750sc Nighthawk.. I was trying to get my tail lights working and saw smoking after replacing the old round fuses. Now every time I try to hook up the battery, the fuse blows at the solenoid. All I have done is put new fuses in the fuse box and put a brake master cylinder on it. Maybe I have...
  20. G

    Charging

    Morning All, and Happy New Year. Please could I get help with worst possible problem (for me anyhow). I can ride my 1980 750 Custom sometimes, and everything is good. Battery spins the starter like crazy, and bike starts. Other times the battery is basically completely dead, and I have to push...
  21. Luis Etchenique

    frame-mounted OKI Spark Units and Rectifier

    Now in the process of re-assembling my electrical, I have relocated some of the items: The two OKI spark units and the rectifier. Question: Do these units need to be insulated, or can I mount directly on the frame without insulation ? I am not sure if they use the frame's ground polarity to...
  22. Butscut

    Wiring to Pulse Generator

    Hey Folks - Random question, I have an '82 CB750F Supersport. There are two blue and two yellow wires connecting the spark units to the pulse generator. Qn - does it matter which way round they connect, is this important? I understand that the two yellows feed one spark unit and the blues the...
  23. Luis Etchenique

    Fuse Box - '79 CB750F S/S

    In converting this bike into a race-replica, I had to reconfigure the electrical harness, build a junction box under the seat, shorten some of the control wires ... and now I am confronted with the fuse box. I have deleted the turn signals, and I have built a new dashboard which includes the...
  24. Luis Etchenique

    ‘79 Cb750F S/S Generator Output

    hello everyone — does anyone know what is the generator output in volts at idle of a CB750F Super Sport ? I was considering purchasing a battery which requires at least 13.1 volts of output from the generator at idle speed thanks for any info you could provide me with
  25. Luis Etchenique

    - Eliminating Keyed Ignition Switch -

    Hello all -- I am considering eliminating the keyed ignition switch on my race-replica bike, and substituting with an " on/off " toggle switch. Has anyone done this before ? I would welcome any comments, suggestions, or opinions. Thank you as always !
  26. Idontknowcrap

    Bike won’t start.

    I bought a bike recently and only got 1 decent ride And then i started having problems. I put brand new battery. But the lights are extremely dim to almost nonexistent. Engine turns but it won’t fire up.
  27. I

    I am having to use different wiring diagrams on my 77 Cb750

    So what I thought would be a simple process has me thinking my life decision, I have multiple diagrams and right now it seem like I am using one from 76 and then another from an unknown year. I am having issues mainly because I have some wire colors that aren’t on any diagram. Of course it...
  28. M

    curious noise when turning on ignition.

    My 1977 CB750A has an interesting condition and I was hoping someone might have an idea. When I turn on the ignition switch, occasionally I will her a loud pop-like a firecracker. The bike still runs, but what would cause this to happen and how can i stop it from happening? It does not happen...
  29. I

    Colored wiring diagram

    So while wiring in my digital gauge I decided to take the wiring diagram I found and color code it. Not sure if anyone needs this, but figured I’d share it just in case.
  30. I

    Installing acewell md085-553 on a 77 cb750k

    So my stock gauges are trash and I want a single gauge but the previous owners at some point cut all the wires from the gauges. So does anyone have any tips or tricks on going from stock duel gauges to a single digital multifunction gauge?
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