1982 V45 Magna electrical glitch

[insaneV4Honda]

I am new to the site and I like what I see. I am having a problem with one of my bikes (yes, I have 2 of them 82 and 83 Magnas). I am sorry for how long this is but I felt it was important to list everything I noticed about it. I have completely rebuilt my 83 so there aren't too many problems I can't handle but this one stumps me. This is the problem I am experiencing with my 1982 Honda V45 Magna. Some of these items may not even relate to the actual problem however they are things I have observed during my troubleshooting of this problem. The “tail light” warning lamp on the instrument panel will illuminate intermittently. It does not flicker on and off brightly; it will come on very dimly and then get brighter and then go dim again. It acts just like the low fuel light does when the fuel tank gets low and it will come on and off a few times before the light is completely on. These are the conditions I have noticed when the tail light warning lamp comes on. It always happens with the tachometer between 1500 and 4500 RPM. It will do it in any gear selection and at any engine operating temperature. It happens weather the fuel tank is full or empty. When the turn signals are activated during this condition (either one), they will blink really fast. If I squeeze in the clutch while I am going down the road, this condition stops once the RPM is below 1500 RPM. The headlight will also get brighter when I squeeze in the clutch and the tail light warning light goes out. The other thing I have noticed is the bike lacks normal power above 5000 RPM. It almost feels like I am hitting a rev limiter but the bike will rev up through the normal range of RPM. It just feels like it is missing at high speeds. My 83 feels like it will rip you off the back of the bike no matter what RPM you are at. While cruising at 65 MPH and going uphill, it will feel like it is surging; even if I give it full throttle. The bike is also getting really great mileage; 50-54 MPG. This is not a bad thing with fuel costs so high, but my 83 that I have just rebuilt only gets 45 MPG tops!

Now this is what I have done to the bike not necessarily because of this problem;

1. Changed the stator assembly
2. Changed the voltage regulator
3. Changed the battery
4. Changed the left hand control switch assembly on the handlebars
5. Changed the turn signal relay
6. Changed the spark plugs
7. Changed the spark plug wires
8. Changed the ignition coils (both)
9. Changed both CDI boxes
10. Changed the tail light / stop sensor
11. Did an ohm check on the pulse generators- checked OK
12. Temporarily by-passed the low fuel sensor; problem still exists
13. Temporarily by-passed the clutch safety switch; problem still exists
14. Checked the operation of the front and rear brake switch- operates normally

The tachometer thing is where I think the problem is at. The question remains, is it the tachometer or is it the engine related to those RPM's. Sorry for so much detail. Any help is greatly appreciated! Thanks! Sean

[ceemes]

I am new to the site and I like what I see. I am having a problem with one of my bikes (yes, I have 2 of them 82 and 83 Magnas). I am sorry for how long this is but I felt it was important to list everything I noticed about it. I have completely rebuilt my 83 so there aren't too many problems I can't handle but this one stumps me. This is the problem I am experiencing with my 1982 Honda V45 Magna. Some of these items may not even relate to the actual problem however they are things I have observed during my troubleshooting of this problem. The “tail light” warning lamp on the instrument panel will illuminate intermittently. It does not flicker on and off brightly; it will come on very dimly and then get brighter and then go dim again. It acts just like the low fuel light does when the fuel tank gets low and it will come on and off a few times before the light is completely on. These are the conditions I have noticed when the tail light warning lamp comes on. It always happens with the tachometer between 1500 and 4500 RPM. It will do it in any gear selection and at any engine operating temperature. It happens weather the fuel tank is full or empty. When the turn signals are activated during this condition (either one), they will blink really fast. If I squeeze in the clutch while I am going down the road, this condition stops once the RPM is below 1500 RPM. The headlight will also get brighter when I squeeze in the clutch and the tail light warning light goes out. The other thing I have noticed is the bike lacks normal power above 5000 RPM. It almost feels like I am hitting a rev limiter but the bike will rev up through the normal range of RPM. It just feels like it is missing at high speeds. My 83 feels like it will rip you off the back of the bike no matter what RPM you are at. While cruising at 65 MPH and going uphill, it will feel like it is surging; even if I give it full throttle. The bike is also getting really great mileage; 50-54 MPG. This is not a bad thing with fuel costs so high, but my 83 that I have just rebuilt only gets 45 MPG tops!

Now this is what I have done to the bike not necessarily because of this problem;

1. Changed the stator assembly
2. Changed the voltage regulator
3. Changed the battery
4. Changed the left hand control switch assembly on the handlebars
5. Changed the turn signal relay
6. Changed the spark plugs
7. Changed the spark plug wires
8. Changed the ignition coils (both)
9. Changed both CDI boxes
10. Changed the tail light / stop sensor
11. Did an ohm check on the pulse generators- checked OK
12. Temporarily by-passed the low fuel sensor; problem still exists
13. Temporarily by-passed the clutch safety switch; problem still exists
14. Checked the operation of the front and rear brake switch- operates normally

The tachometer thing is where I think the problem is at. The question remains, is it the tachometer or is it the engine related to those RPM's. Sorry for so much detail. Any help is greatly appreciated! Thanks! Sean

My '85 V45 Sabre is currently in the shop getting electrical repairs. One of the CDI's fried out knocking out my two front pistons and the turn signal self canceler really fried out and causes short that melted part of my wiring harness. You may want to check some your electrics for shorts before it causes you really major and expensive repairs....I am looking at between C$800 and C$1000 in repairs.

[insaneV4Honda]

I know exactly what you mean and that is why I am looking for ideas. I feel pretty confident that I have a short to ground which is feeding back into the tail light warning lamp, turn signals and headlight but the short seems to have resistance to it. When it is just idling, it does not happen. It only happens at engine speeds between 1500-4500 RPM. I'm just looking for ideas on a place to start looking for the problem. My next step is to disconnect the tachometer from the system and see what happens. Thanks for the feedback! Sean.

[Johnj]

Sean, I would take an old inner tube and cut it so I could wrap it around the wiring harness in various areas of the bike. Wrap it around the harness going to the tail lights/turn signals on the back of the bike. If your problen goes away then you know your short is in that section of the harness.

[insaneV4Honda]

Thanks for the tip! I should probably start up at the front of the bike; you know where they cram all of those wires behind the headlight! I will try your isolating technique to see if I can find the problem. I think I have changed enough components to rule out a box failure. Actually, the one component I still question are the pulse generators. They check out fine for a resistance check. In the past, I have had stator assemblys with a bad phase in them. The bike would run fine; up to a certain RPM - then they would cut out. I changed this one so I am ruling it out...but the pulse generators are original. I have been reserved at cracking the case. I have been hopeful for an easier fix. Its got to be in the wiring harness. Thanks again. Sean

[Johnj]

Also examine the wires. You may find a chaffed area on a two adjacent wires.

[Evil Twin Brother]

I have a 85 Goldwing, when I first got the bike the pulse generators were bad, this would cause the bike to die. It only happened when the bike was warming up. Your problem sounds system wide, I would check all ground connections not just on you battery.

[insaneV4Honda]

Thanks for the information. I talked to some more friends last night and some other suggestions were to look into the ignition switch for a possible intermittent short. I am going to rule out everything I can before I crack the case ans swap out the pulse generators. Keep the suggestions coming! Thanks. Sean.

[insaneV4Honda]

I have a 85 Goldwing, when I first got the bike the pulse generators were bad, this would cause the bike to die. It only happened when the bike was warming up. Your problem sounds system wide, I would check all ground connections not just on you battery.

I've been doing some thinking about your comments and needed to ask you a question or two. I do have a problem with this bike when I first start it up. If I let it idle until the temp gage started to indicate it was getting warm, I could drive it and everything was OK. If I start it cold and then take off within a minute or two, the engine would cut out above 3K RPM. If I keep it under 3K for the first few miles or so, things are fine. It definately feels like a loss of ignition rather that fuel. I first attributed this condition to dirty carbs or a bike that just did not like the cold. One thing I do remember is when the bike would do this, the tach would jump all over the place and the bike would completely fall on its face if I did not upshift. Like I have said previously, one thing I consistently experience is a pulsation at a constant RPM above 60MPH. Does any of this dound familiar to the problems you had with your Gold Wing? Thanks. Sean

[Evil Twin Brother]

When my pulse generators were bad, the bike would die when my temp gauge showed 4 bars (digital gauge). It would be hard to restart but when it got up to temp it was ok, if it cooled down would start problem all over again. I believe what was happening one of my generators was dropping out and my ignition module would shut down because it was missing one of the pulse generator. Your ignition box may not act the same, I never had any problems with performance it would just die. The old generators showed no signs of damage and when I did a resistance check they showed good. Could you switch you ignition box out with you other bike to see if that is the problem? Sounds like you box or generators to me. GOOD LUCK!