Topic: cb750a alternator.

[MoMo]

Man I put that shifter cover back on and my shifter pedal seems like its a lot more difficult to shift in to gear now. down shifting into neutral from drive isn't so bad but lifting the pedal up from neutral into drive and then into over drive is a pain in the butt now.

You cleaned every part of the cover, especially the area where the shaft goes through?  Make sure the cover is flush against the block and tighten in a criss cross pattern.  If it worked well before it has to not quite be installed correctly... Larry

[05c50]

Man I put that shifter cover back on and my shifter pedal seems like its a lot more difficult to shift in to gear now. down shifting into neutral from drive isn't so bad but lifting the pedal up from neutral into drive and then into over drive is a pain in the butt now.

You better take a second look at the shifter, it should take very little effort to move it. Maybe the kickstand interlock is out of wack.

..................Paul

[maliveline]

it is an automatic but i have a low gear and a high gear and neutral.

[maliveline]

how do you fix the kick stand interlock?

[05c50]

As you probably know, the interlock keeps the shifter from being moved to the drive position when the side stand is down. Try disconnecting the "neutral keeping spindle". That's the other shaft that comes out through the side cover.

..............Paul

[maliveline]

does that mean I have to take the shifter cover back off?

[05c50]

No, not yet, just disconnect the linkage from the extra lever and see if the shifter moves freely.

..............Paul

[maliveline]

https://mail.google.com/mail/?ui=2&ik=0623f7056f&view=att&th=12cdd81d2685bd03&attid=0.1&disp=inline&realattid=f_ghmqd2870&zw


Heres a picture of my setup. can you tell me the linkage your talking about please?

[05c50]

Sorry, your link didn't work for be, but here's a picture of the shop manual (I don't have a scanner). Remove the lever that the red arrow is ponting to. It connects to the side stand with the rod and spring.



..........Paul

[maliveline]

my bike doesn't even have that lever. I wish you could just upload pictures to this website..

[maliveline]

i guess what i meant to say is how do you upload a picture to this website?

[TwoTired]

Below the type in box while you do the reply is "additional options"

Then attach and browse for each picture you wish to upload.  Observe the size allowed and the quantity.

[Jerry Rxman Griffin]

Or if you're computer tech compromised like me you might load your pictures to a free site like PhotoBucket then highlight and copy the IMG Code below your picture and simply paste it in here. With this you don't have to worry about a size limit. I never could make them the right size to use our additional options/attach function

[maliveline]

I think Im gonna make a handshifter thing at my work because I'm not into foot pedals anyways. maybe I will post pics someday.

[Spanner 1]

The lever 05c50 is referring to should be attached to that front ( unused ) spindle. The chrome rod with the adjuster on it ( that's just hanging down loose in your pic. ) goes between the missing lever and the kickstand. When the stand is in use the lever turns that spindle a little counterclockwise which prevents the shifter from engaging L or D..... so obvious thing to try would be to grip this spindle with a vise-grips and turn it clockwise slightly to see does it free-up the shifting mechanism  ... if it fixes the problem, then you'll have to think up a way to keep it in that position as it will go back to 'lock-out' by itself IMO, probably when you 100miles from home without a vise-grips, or try to find the missing part............

[05c50]

I guess the question I have, is how did it shift before you took it apart. The interlock is on the bike as a safety devise so you that you don't leave the bike in gear when you put the stand down. Spanner is right, the link seems to be dangling there. The system works very well when it is all there and adjusted properly.

..............Paul

[maliveline]

the link thing dangling there is ducted tapped to my kick stand lol. it was like that when i bought it. for some reason my bike worked pretty decent when i first got it but now its really hard to shift
after i assembled everything. at the moment it works i just have my shift pedal up at an angle and i just hit it with my heel to shift up to L and H gear. its kinda ghetto but it seems to be working lol.

[05c50]

Try turning the other shaft as Spanner suggested. It might just work.

.................Paul

[lucky]

One thing all of the electronics experts are leaving out is this.

Set the meter on ohms X 200 scale to do the slip ring test (the copper rings the brushes rub against). Very important.

My 1978 model CB750 does not have brushes.

That is why I had trouble with math in school, too many details left out and just assumed that you would know.

[HondaMan]

On the "A" bikes, the regulator sets the field coil current, which then excites the stator coils to generate power. So, a PROPER test would include bypassing the regulator directly to the field coil, then checking the stator output. If the field coil is shorted (rare), he would have been confronted with melting wires: if open (less rare), he would have noticed (if he bothered to check) that no current was flowing to the field coil. And, when no current flows, no stator output is possible. That's the proper test method for these bikes.

Although I hate to even say it, today's bike shop wrenches blow, if it is electrical. They will say anything they can to get it off their bike lift because they are often paid on commission, part of the labor, and have absolutely no clue how to fix or test electrical. His comment of "not available" should have been the first comment before charging you a dime for an exam of it.

If you have  friend available nearby who can read a schematic, then do this test:
Disconnect the regulator.
Jumper the field coil's wire to the bike's BLACK wire with a temporary jumper.
Put the meter leads on the battery (on DC volts range) and start the bike. Watch the battery voltage for a rising reading when the bike is held at 2500 RPM for about 1 minute or so: it should climb upward in volts if the alternator is working.

Shut off the bike, then connect the meter in place of the jumper wire above, as the meter to AMPS range (more than 2 amps) and move the meter's test leads (usually just the Red one) to the "A" terminal so the meter will read amps. Turn the bike's key ON, see if you get a reading. It will be an amp or two more if the field coil is not shorted, but more than 4 amps if it is shorted.

Troubleshooting techniques:
If the bike's main fuse (15 amps) blows when you turn the key on with this jumper in place, this indicates the field coil is shorted (i.e., if you have jumpered it correctly). If the fuse blows after the bike has been running for a minute or two at 2000+ RPM, the field coil may be partially shorted, and the battery voltage will fall downward during this test.