Topic: Patina Hyena - 550/650 674cc Hybrid Cafe Build

[Wredas]

Just finished reading the thread, and I thought it was great fun to read. Really outstanding work and the bike sure does look good. Sounds great too!

[DaveBarbier]

Just finished reading the thread, and I thought it was great fun to read. Really outstanding work and the bike sure does look good. Sounds great too!

Thanks Wredas! Always more to do but it's coming along nicely.


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1978 Honda CB550K

[DaveBarbier]

Just to let you guys know, I put a bunch of parts up in the for sale section. Some stock, some aftermarket.

Bike is running really well. Only thing is a slight flat spot at wide open throttle. Going to first take the rack of carbs off and clean them. Maybe debris got in or they got a little gunked up from sitting over the winter. If that doesn't fix it I'll be doing plug chops, or hopefully getting some dyno time in.

The flat spot wasn't there with pods but it seems to be there now with velocity stacks.


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1978 Honda CB550K

[DaveBarbier]

Just checked float height by the clear tube method. All are completely in line with the float bowl seam. I'll have to fix that. I don't remember setting the floats that low. If I remember correctly the stock float height is 12.5 mm as shown to me by TwoTired. Going to remove the rack and adjust floats and clean the jets and whatnot. Shouldn't the fuel level be about 4mm below the bowl seam?


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1978 Honda CB550K

[DaveBarbier]

Haha, something is not right here...



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1978 Honda CB550K

[Maurice]

Did you screw it on by hand and forgot to tighten it?

That would explain the flat spot. Must've been smoking like a steam locomotive too

As for clear tube method I'm not sure... Haven't touched my carbs in a long time.

Maybe I missed it, what do you use for air filters?

[DaveBarbier]

Did you screw it on by hand and forgot to tighten it?

That would explain the flat spot. Must've been smoking like a steam locomotive too

As for clear tube method I'm not sure... Haven't touched my carbs in a long time.

Maybe I missed it, what do you use for air filters?

Well, last year when I figured out that the PO drilled out the jets, a family friend came by to help who knows old bikes. He was actually the one who shined light on the drilled pilot jets (I had no idea). We disassembled them and cleaned them and set them right. It was one of us I'm sure. We both probably thought the other guy did it, haha. And weirdly, I didn't notice it smoking at WOT. Maybe it was, haha.

So anyway, I re-cleaned them just now (they were pretty spotless) and found my float height was just about 13mm each float, maybe 12.8mm This screen shot that TwoTired sent me says 12.5mm. But with 13mm my float heights are almost exactly flush with the carb seam.




The outer carbs are like this but the inner two are a hair lower. Should I change the float height to an older year like 14.5mm?

Part of me says keep it and change one thing at a time (screw main jet back in) then go from there.

I'm running velocity stacks.


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1978 Honda CB550K

[Maurice]

If it's running ok leave the level alone. Your flat spot is probably due to the main jet missing and running real rich on one cylinder WOT. The lose jet was only on one, correct?

I don't remember on these carbs, but most like the gas level around bowl level.

I know you're running stacks, how do you filter? Screens or foam inside? Any pics?

[DaveBarbier]

If it's running ok leave the level alone. Your flat spot is probably due to the main jet missing and running real rich on one cylinder WOT. The lose jet was only on one, correct?

I don't remember on these carbs, but most like the gas level around bowl level.

I know you're running stacks, how do you filter? Screens or foam inside? Any pics?

Ok, that's what I'll do and then test. Yeah, it was just one jet that fell out.

Oh right, I'm running screens. Pics...let me see. They come with the brass screens from Steel Dragon.



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1978 Honda CB550K

[Maurice]

Did you tilt-shift that picture some or is the depth of field really short? Might want to take one with the chain on this does not look serious.

While the brass screens will prevent bugs, critters and your pants from being sucked into the carbs, I would not be comfortable using this in the long run... That does not look like it would filter out dust. That rear wheel does generate a fair amount of it. I think I saw somewhere someone cut round pieces of UNI filter and stuck them in there behind the screens.

Bike looks great, I think a set of emblems on the tank would really make it.

[DaveBarbier]

Did you tilt-shift that picture some or is the depth of field really short? Might want to take one with the chain on this does not look serious.

While the brass screens will prevent bugs, critters and your pants from being sucked into the carbs, I would not be comfortable using this in the long run... That does not look like it would filter out dust. That rear wheel does generate a fair amount of it. I think I saw somewhere someone cut round pieces of UNI filter and stuck them in there behind the screens.

Bike looks great, I think a set of emblems on the tank would really make it.

Good eye, but you didn't notice the lack of a clutch lever either, haha. It's an Instagram picture so yeah, I added a bit of tilt shift. I'll take a new picture soon with all the parts on it, haha.

Yeah, I know, filter media would be best. I'm risking it though. Maybe eventually I'll add some, but right now it'll be unfiltered. I accept it's bad for the motor.

A lot of people say to put emblems on it but I like it like this. It gives more of a barn find, utilitarian, only what's needed kind of feel. Thanks Maurice. And thanks for the carb help.


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1978 Honda CB550K

[DaveBarbier]

Did you tilt-shift that picture some or is the depth of field really short? Might want to take one with the chain on this does not look serious.

Here's a "serious" picture. This one actually has all components installed! Just cooling down after a nice long ride. Zero hesitation at WOT! It actually startled me a bit that it had that much power, haha. And about the floats. I pulled the plugs earlier and noticed the outside cylinders were a little more rich (plugs were darker) than the inner two. And those were the ones that had the fuel level almost to the seam. The inner ones were still high, but not that high. I did end up adjusting the float height to get them all to match. Now they're just about 3mm from the seam. Weird thing, though, the float height measurements are very different.
#1: 16.3mm
#2: 13mm
#3: 15mm
#4: 16.3mm

With those settings they're all the same fuel level, checked by the clear tube method. Not sure if that variance is normal or something is very wrong. But it idles great and pulls through all gears with no stutters. Will pull plugs and have a look-see tomorrow perhaps.

Motorcycles are really great.




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1978 Honda CB550K

[SOHC4 Cafe Racer Fan]

Motorcycles are really great.

Damn straight! 

[DaveBarbier]

Question: Is there a better alternative to these Emgo key switches? If you watch the video you can see just the speedo illumination (not sure why just the speedo) flickers if I wiggle the key while in the "on" position. Do these things need to be grounded with their body? I just have three wires coming out of it. I smack the headlight and reach in to wiggle the wires just to make sure it's not other wiring. It seems to be only the key switch.

Any help would be appreciated. Thanks.

Also, when riding home tonight I went to switch on my high beams and the entire bike went dark. Engine shut off and wouldn't turn back on. All lights went off except for the speedo illumination. Weird, yes. Thought I blew a fuse but waited a second and turned everything back on and I was good to go. I did notice that my headlight can shut off if I play with the high/low switch. Any takers on this one?


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1978 Honda CB550K

[Restoration Fan]

I think there's a short somewhere in that switch body.  To interrupt current like that cannot be an intended outcome of bumping the key.

[SOHC4 Cafe Racer Fan]

I agree with Ron.  I think you have loose wire in the key switch.

[calj737]

You have a short somewhere. But it's not isolated to the key as the key switch is not involved with the headlight circuit at the handlebar.

It's odd, you say only 3 wires from the backside of your key switch? Stock is 4 and replacement switches I've seen are all 4 too. Did someone prior to you remove a wire? Can you tell us what 3 colors you do you have?

Also, testing the key switch operation and voltage/resistance would be handy:
- In the OFf position, backside of Key, you should have 12v on red
- ON position, you should have it on Red and Black now, plus Brown/White
- Acc mode, 12v on Red, Brown and Br/Wht but not Black

And how about resistance across the switch? Emgo switches are pretty low quality and are often involved in poor electrical performance. (Especially if a PO mucked with them)

For your handlebar, I'd check to make sure the housing is properly and firmly connected to GROUND thru the bars. Resistance and continuity checks from housing to engine frame bolt is a decent test.

[DaveBarbier]

Thanks everyone. I will go out and get some info for you with my multimeter. But just a little info. Yes, it's a three wire universal Emgo switch. I got rid of the stock one because it was too big. I wired it up with a relay to help lessen the load and hopefully save this little thing from burning up. I posted a question a while back on how to wire it up and this was Hondaman's reply which is how it's currently wired.

"Connect the Red/White wire through a fuse to the #30 post on the relay. This is the "source" power. Connect the bike's Black (Ignition) wire from the harness (cut it away from the keyswitch) to the #87 terminal on the relay (this is "switched power", then). Connect the Black that you cut from the key to the #85 terminal, and connect the #86 terminal to Green (ground). These last 2 are the coil of the relay: when you now turn on the Key, it connects the Red/White (through the fuse) to the Black. The Brn/Brn-Wht wires stay on the keyswitch, and control the Park light and taillight stuff."

Link to thread if you care. It also has the wiring diagram of the switch I'm using.
http://forums.sohc4.net/index.php/topic,134413.0/all.html

On the actual switch I BELIEVE what's connected is a red to one post, a black to another and finally the brown and brown/white together on the last post. I can double check that when I'm out there.

Because I have a relay on the switch, will I have lower numbers when I measure with the multimeter?
(Electronics aren't my forte even though I wired this up and completely redid the wiring under the seat successfully. The knowledge seems to enter my head only for the amount of time needed to complete the task. Then it gets replaced with beer and the next project.)


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1978 Honda CB550K

[calj737]

Resistance shouldn't change with the relay.

[DaveBarbier]

Continuity/resistance from high/low switch housing to engine bolt: there is continuity and it's .6 ohms resistance. Is that ok? My clipons are painted black but it might have a path going through the clutch cable. I'll sand some paint off and retest. Does the high/low switch housing ground itself through the body or is there a grounding plate or pin?

Key switch:
OFF
13.3 volts to red only.

ON
13.3 volts to red
12.7 volts to black
12.7 volts to brown, brown/white

Key ACC:
13.3 volts to red
12.7 volts to brown, brown/white

Can I measure resistance while it's connected to power? My meter clicks when I do that. I think it's bad and I'm tripping a little internal breaker. Right? The key switch must be removed from power, no? With ground from battery disconnected, resistance values are as follows:

Key OFF:
Open Loop on all contacts.

Key ON: (while wiggling key)
Ranges from .4/OL from battery to ignition and ACC

Key ACC: (while wiggling key)
Ranges from .4/OL from battery to ACC

Seems to me the key switch is bad. And I can see the power contact on the back wiggles even after it's tightened down. New key switch, no? I see on eBay an OEM 4 wire CB550 small key switch. These have to be better quality than this EMGO, right? Any other small key switches that you guys recommend?



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1978 Honda CB550K

[DaveBarbier]

Anyone with thoughts on my numbers? Specifically the resistance value of the high/low switch housing to engine bolt? I bought the OEM 1975 CB550 (four wire) key switch. Plan on just wiring it up to my three wires.


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1978 Honda CB550K

[Maurice]

If you have a ground somewhere, you need to measure continuity, not resistance. Besides, it looks like an intermittent ground, which means you can measure all day and not find anything until you wiggle the right spot...

It's a PITA for sure, inspect connectors inside of harness, etc. There's probably some wire insulation cracked somewhere that could be causing this. Could be key switch itself? Does it do it when you hotwire the thing?

[DaveBarbier]

Oh, well I'm 99.99% sure the switch is crap. I wiggle the key in the switch while the switch is disconnected from the bike and the continuity tone on my meter is intermittent while testing the contacts. To me that means the switch goes in the bin.

There is also continuity from the high/low switch housing to an engine bolt. That tells me the housing is grounded but the resistance of that ground is .6 ohms. Is that ok? Does resistance not matter in a ground as long as it has continuity? Regarding the high/low shutting off the headlight temporarily or while I wiggle the little switch lever, I know and saw that the contacts are a little worn. I tightened it down and cleaned them but have yet to test it to see if it's better. I might replace that so that's not a concern right now.


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1978 Honda CB550K

[Maurice]

I don't think it matters that the housing itself is grounded, as long as wires and stuff that is powered inside is insulated from it. Which it may not be... Now the HI-LO switch can probably have a position in-between where there won't be any light connected at all, the way it's made it looks like you could wiggle the switch itself and interrupt the flow.

If in doubt take the switch out of the equation by wiring low straight at the plug with a jumper (and electrical tape in case) and test things out. To find a short you'll have to eliminate stuff one after the other.

[DaveBarbier]

I don't think it matters that the housing itself is grounded, as long as wires and stuff that is powered inside is insulated from it.

Hm, ok, makes sense. Yeah all my wires inside are in good condition. I looked them over when I took it all apart to route the wires through the bars.

...the way it's made it looks like you could wiggle the switch itself and interrupt the flow.

That's exactly what I think is going on. The switch moves vertically for the high/low but when I press it horizontally to the right it shuts it off. I can see it moving away from the contacts when I look inside. Glad you said that!
I originally thought my two issues were related but I think now that it's just a coincidence. Faulty key switch mixed with high/low switch a little worn. Will replace the key switch this weekend and report back. Thanks!


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1978 Honda CB550K