Topic: CB550 Four K3 1979

[Cruiser]

Took her for a spin without the air filter and without the breather tube, no difference in handling (meaning it drove very nice yet again) but also no difference when I looked at the plugs. Still black as night. Did a 15km test ride. I assume they would've cleared up a bit if it was leaner then before.

Guess I'll try the Keihin needle/main jet now.

Verstuurd vanaf mijn SM-A525F met Tapatalk

[Deltarider]

I don't know why some filters have the bigger exit and others (including OEM) the smaller, nor do I know if it makes any difference.

[Deltarider]

Just to be sure: when you say: my plugs are still black, what part of the plugs do you refer to. Realise that only the ceramic nose can give an indication. The bottom rim of the threaded part will always be black more or less. I can't remember I have seen pics of them.

[RAFster122s]

Plugs that are carbon or oil fouled with deposits are not going to magically change from a brief ride. If you put new plugs in, then you have current conditions being reflected. Otherwise the motor is going to have to get hot enough long enough to burn off previous deposits. A short ride around the block or short hop to grocery and back is going to give you deposits from that mixed loop, most of which is low speed operation where the motor is naturally richer...

[Cruiser]

I'll take her for a longer ride.

I'm referring to the arched clip where the spark happens.

Interestingly enough, there are differences in the Keihin and Keysters concerning holes in the main jet tube.

Verstuurd vanaf mijn SM-A525F met Tapatalk

[Deltarider]

Those holes are the last thing I'd be concerned about. I never experienced any difference after I had cleaned mine some decades ago. There's much emphasis on them in this forum and only this forum. I have no idea what people expect of them. The air passing through them is just for pre-atomizing the fuel somewhat and, contrary what some seem to believe, hardly contributes to the air for the combustion, if at all. How much would that contribution be? 0,1%?

I'm referring to the arched clip where the spark happens.

I don't know what you mean. A video clip?

[Cruiser]

Those holes are the last thing I'd be concerned about. I never experienced any difference after I had cleaned mine some decades ago. There's much emphasis on them in this forum and only this forum. I have no idea what people expect of them. The air passing through them is just for atomizing the fuel and, contrary what some seem to believe, hardly contributes to the air for the combustion, if at all. How much would that contribution be? 0,1%?

I'm referring to the arched clip where the spark happens.

I don't know what you mean. A video clip?

Well, I've just let it idle with the Keihin jets and I assure you there is a huge difference. Its the first time she idles this clean.

Even my 11 year old son came rushing into my workshop asking why this bike sounds so different

I'll let her cool down first and then do another valve clearance check (was on my list and since I've got the tank off now...).

After that I'll do a longer run.

See attached for a picture of the spark plug before the tests I've done. How black do you like your coffee?


Verstuurd vanaf mijn SM-A525F met Tapatalk

[Deltarider]

That one is definitely sooted. Makes me wonder about your air intake tract. I'd do a testride without the air filter element. To arrive at a reliable comparison and also save your intake valves from contamination, I'd disconnect and/or plug - at least temporarily for that test - that blow-by-gas element. 

[Cruiser]

So... This is definately a different bike now.

Cyl 2 runs as warm as the others. The idle is so good now. Runs equally good in the high revs.

Plugs came out like this after a 25km ride (still not long enough, but had no time). I'm doubting that its maybe too lean now. I'll order new plugs to be sure.

This is with the main jet clip in position 2 and with the air filter and blow-by-gas breather tube installed.

Also the high revs on cold startup are far more normal now. Now we are talking about maybe 200 to 500 rpm extra.

[Deltarider]

Plugs that are carbon or oil fouled with deposits are not going to magically change from a brief ride. If you put new plugs in, then you have current conditions being reflected. Otherwise the motor is going to have to get hot enough long enough to burn off previous deposits. A short ride around the block or short hop to grocery and back is going to give you deposits from that mixed loop, most of which is low speed operation where the motor is naturally richer...

You don't need new plugs. As long as they function and do not short, they are fit for the job. Just do a long enough ride before you begin the actual test. I'd limit the test to around cruise at 5000rpm.
When your plugs look OK at 5000 rpm, you can for the rest rely on the precision of the Keihin parts, given you have the stock air intake.
Some will say you need a looong distance for a looong time to test. Not in my experience. A couple of minutes will do. Just pull the clutch and turn the killswitch to OFF simultaneously and roll to a parking space. Plugs are easy to remove when hot. Use the Honda wrench.
Oil fouled plugs is another subject though. They need to be replaced before the test run. The common complaint is that todays unleaded gas does not give much color indication anymore. You can overcome this by adding a spoonful of castor oil to your tank which will give the color indication we used to have in the 'leaded years'.
 

[Cruiser]

Next issue on the list

My blinkers sometimes go haywire. They blink 3 or 4 times, then the blinker light remains on. If I then flip the turn signal off and back on, it works again for a couple of blinks and stops again.

I've also noticed when I switch the blinker on while I'm on the throttle, I get a slight hesitation. Its like the engine has no spark for a split second, just at the moment that I switch it. Otherwise no impact.
Battery is fine (new as well), gets charged normally and has great voltage (14V with running engine and 12.7V when not started).

I've already cleaned the connectors at the blinker module. Would this be a faulty blinker module or maybe still some bad ground somewhere (possibly the switch itself?)

[newday777]

Have you replaced the flasher yet?

[Deltarider]

First read what it says on your flasher relay. Then check the wattage of your bulbs corresponds with it. Usually 21 or 18 Watts in our part of the world. I hope you don't have LEDs.

[...]
I've also noticed when I switch the blinker on while I'm on the throttle, I get a slight hesitation. Its like the engine has no spark for a split second, just at the moment that I switch it. Otherwise no impact.
[...]

This is strange. A thing I'd look at: are the fuses OK, are they the right ones and are their ends and their clamps clean. They should not get so hot, you can't touch them.
You could do a V4-measurement to see all Volts 'arrive where needed'. It is explained here:

It's just 4 steps with the same meter. When you look at the pics long enough, you'll get it. Each picture shows two measurements.
Let's say there's a problem, something is not working right: a somewhat dim lamp.
Step 1: you measure the potential over the battery terminals. Here it is 12,0 V. This is now your reference.
Write it down: V1 is 12,0 V. Then one step to the right, which is step 2. You measure the potential over both sides of the part that you suspect. Here you measure a potential of 11,0 V. Write that down: V2 is: 11,0 V.
Hmm, one volt does not make it from Batt POS to Batt NEG, so to speak. We want all Volts to pass. Where can I look for that missing volt?
Step 3. Check if there's any potential over Battery POS and POS side of the lamp. Ideal outcome would be 0 (zero), indicating there's no resistance and all volts arrive. In our example 0,1 V is missing. This is acceptable. BTW, you can interpret that little square as things in between like a fuse and/or a switch.
Write down: V3 is: 0,1 V.
Now check the NEG side of the route: the potential over Batt Neg and the NEG side of the lamp. In this example we measure 0,9 V. Write that also down: V4 is: 0,9 V.
Before we begin interpreting our results, let's first check we did the V4 measuring right.
You only have to remember one formula: V1= V2+V3+V4. Always.
So in our example: 12,0 = 11,0 + 0,1 + 0,9. Conclusion: we did it right. As already said, the 0,1 V missing in the POS route is not much of a problem. Possibly there is some minor resistance by a fuse and/or a switch. Not much to worry about. The 0,9 V in the NEG route is a reason for concern however. But at least we now know, where to look in order to locate it. In our example, it's probably a rusty, dirty or loose connection. Could be the thick Batt NEG cable, connected to a recently powdercoated frame.
Ofcourse this is a simplistic representation. Depending on 'obstacles' like switches and/or fuses, we may need more steps to perform, but V1 must always be the sum of V2 and V--n. Also realise, I've limited myself here to describing a situation, where a component is not working a 100%. There's also the possibility ofcourse, something is not working at all. I'd then start by isolating that part first and connect it directly to a known good battery to verify that part is OK.

[Cruiser]

Have you replaced the flasher yet?

I have a Flasher relay on order, so will see if that changes anything.

First read what it says on your flasher relay. Then check the wattage of your bulbs corresponds with it. Usually 21 or 18 Watts in our part of the world. I hope you don't have LEDs.

[...]
I've also noticed when I switch the blinker on while I'm on the throttle, I get a slight hesitation. Its like the engine has no spark for a split second, just at the moment that I switch it. Otherwise no impact.
[...]

This is strange. A thing I'd look at: are the fuses OK, are they the right ones and are their ends and their clamps clean. They should not get so hot, you can't touch them.
You could do a V4-measurement to see all Volts 'arrive where needed'. It is explained here:

It's just 4 steps with the same meter. When you look at the pics long enough, you'll get it. Each picture shows two measurements.
Let's say there's a problem, something is not working right: a somewhat dim lamp.
Step 1: you measure the potential over the battery terminals. Here it is 12,0 V. This is now your reference.
Write it down: V1 is 12,0 V. Then one step to the right, which is step 2. You measure the potential over both sides of the part that you suspect. Here you measure a potential of 11,0 V. Write that down: V2 is: 11,0 V.
Hmm, one volt does not make it from Batt POS to Batt NEG, so to speak. We want all Volts to pass. Where can I look for that missing volt?
Step 3. Check if there's any potential over Battery POS and POS side of the lamp. Ideal outcome would be 0 (zero), indicating there's no resistance and all volts arrive. In our example 0,1 V is missing. This is acceptable. BTW, you can interpret that little square as things in between like a fuse and/or a switch.
Write down: V3 is: 0,1 V.
Now check the NEG side of the route: the potential over Batt Neg and the NEG side of the lamp. In this example we measure 0,9 V. Write that also down: V4 is: 0,9 V.
Before we begin interpreting our results, let's first check we did the V4 measuring right.
You only have to remember one formula: V1= V2+V3+V4. Always.
So in our example: 12,0 = 11,0 + 0,1 + 0,9. Conclusion: we did it right. As already said, the 0,1 V missing in the POS route is not much of a problem. Possibly there is some minor resistance by a fuse and/or a switch. Not much to worry about. The 0,9 V in the NEG route is a reason for concern however. But at least we now know, where to look in order to locate it. In our example, it's probably a rusty, dirty or loose connection. Could be the thick Batt NEG cable, connected to a recently powdercoated frame.
Ofcourse this is a simplistic representation. Depending on 'obstacles' like switches and/or fuses, we may need more steps to perform, but V1 must always be the sum of V2 and V--n. Also realise, I've limited myself here to describing a situation, where a component is not working a 100%. There's also the possibility ofcourse, something is not working at all. I'd then start by isolating that part first and connect it directly to a known good battery to verify that part is OK.

Flasher relay says "21WX2+3.4W" Haven't had time yet to open the blinkers itself today, but I'm 100% sure they are not leds. I'll check the Watt's tomorow, however I don't think that's the issue.

Concerning the V4 test, I'll see if I can try something over the blinkers. I know the theory behind the V4 method, however I've never really used it in real life. I just know some very very basic electricity stuff.

Concerning fuses, they are all new and I only have 2x 10A and 1x 15A (main fuse). I did blew the main fuse some time ago on a long ride, however I suspect that was due to the "Buzzer" wires in the headlight not being isolated (they where just cut, and I suspect they touched something and caused a short). Unless that main fuse was blown due to something with the blinkers...

[Cruiser]

All blinkers are 12V, 21W. Seems good. One however was rusted from the inside. Tried to pull it out and all I got was the glass. Had to pry out the socket.

The light was working however .

Swapping it for a new one.

[Cruiser]

So received the new flasher relay today, however this one has 2 pins, old one had 3 pins. I assume one extra is 'earth'?

Any reason why I should or should not run the one with 2 pins?

I'm thinking if the old one had an extra one for earth, then maybe thats why it was holding back for a split second when I flicked the switch (maybe a bad earth connection)?

[bryanj]

Genuine were semi electronic and needed earth the 2 pin one is probably just a bimetallic strip and doesnt

[Cruiser]

Well going to have to dig deeper though since she still briefly cuts out the moment I engage them. Just a microstutter.

[Cruiser]

So wanted to give a little update on the electrical issue.

Got it fully fixed by replacing the fuse box with Hondaman's fuse box. I also cleaned the starter cable, I had a 3V loss over that.

She's running like a dream at the moment!

Still looking online for that rear grab bar though.