Topic: And so...it begins - 1975 CB550F

[Smudgemo]

Hey Jooky, an option (if I'm reading this correctly) for a starter button fix is to replace the plastic housing with all of the original parts and you'll be back in business.  Since it sounds like your parts are long gone, you'll need to find an old one with the important parts.  My neighbor and I created a replacement for the plastic switch housing that is a perfect match for three '76 550s I've fixed.  I don't know if it's the same part for your bike, but it's an option.  If I've read this wrong, then never mind.  The how-to is in my signature below and the part can be got here: http://shpws.me/NkB8

[Jooky]

Well, almost 6 months of radio silence....but I'm back with a big update. Spent the past 6 months working on the bike off and on when time allowed. After addressing the Ignition/Kill Switch assembly, I ordered a new exhaust from Delkevic:

Installation was a breeze and the parts, welds, etc. all seem to be quality, so I'm hoping to get good service life from it. With the exhaust on the bike and much of the ancillary tasks complete, I only needed to get the air box reconnected to the carbs and the gas tank re-plumbed. My original petcock was toast and tracking down a replacement was quite a chore, but thanks to the wisdom of the forums, I located a seller on eBay with NOS Honda parts (granted, it was a $100 just for the petcock; but buy once, cry once I suppose). Everything buttoned up and I rolled her out of the garage for a quick shot:

Things were going well until I installed the battery and encountered a number of electrical issues. No headlamp, no starter button, no tail light, significant voltage drop between the battery and end components. Turns out, despite tending an otherwise new battery from when I bought the bike, the battery was toast. Had a friend come by to help me diagnose the electrical gremlins and after putting his larger battery in series with mine via jumper cables and discovering a blown 7A fuse, we brought this old girl back to life:

Delkevic exhaust sounds pretty good and I think it should open up some more once I put some miles on the bike:

New AGM Scorpion battery from BatteryStuff (thanks forums!) showed up yesterday, so I'm done kick-starting the bike. Also got a fist full of 7A and 15A fuses for future use. My helmet arrived yesterday and I'm on the hunt for a decent textile or leather jacket and gloves (And recommendations folks?). As this is my first bike, I'm playing it safe and respecting ATGATT before hitting the open road. Planning to put some miles on the bike around the neighborhood to wake everything back up in the chassis and see what, if anything, needs tending to.

Fortunately, this bike was in pretty good shape when I bought it in October. It ultimately didn't require a whole lot of effort/parts to get running again. I've never done anything like this before and am super proud and excited to call this mine. I can't wait to ride.

[RAFster122s]

congrats on bringing her back to near riding form again. Sign up for a MSF course, best money you can spend.
Don't forget when going AGATT you need to protect the legs and backside and dress for the slide. You don't want to deal with skin grafts if you can avoid it.

[Jooky]

Made a couple of maiden runs around the neighborhood and close to home and the bike was running great! Today, I took a little bit of a longer ride to a work event. On the way out, the bike ran great. Good power, response, etc. After the event the bike started right up, but as I was cruising home on a level grade at about 45mph, the power started to roll back. I knew I didn't have a full tank, so I switched to reserve and tried to give it more throttle, but the RPMs just kept slowly winding down until the motor cut off. Pulled over and gave the chassis a shake and could feel fuel in the tank and after a min or two of trying to start, it fired back up. Went back on my way and another mile or so down the road, the same thing happens - power gradually rolls off until the engine cuts off. Happened about 3 times on the way back, but I was able to get home under power with the engine running strong.

I think my gas tank may not be venting properly. Before I left the house yesterday (bike was off and cool) I was in the garage getting ready and noticed an odd sound and traced it back to the gas cap venting vapor. Opening the cap was like taking the lid off a partially full soda. When the motor was cutting out yesterday, I can't remember how many times, but I definitely opened the gas cap at least once to check fuel and it was the same thing - bunch of vapor escaping. There wasn't a ton of fuel in the tank yesterday (maybe 2 gallons to start the trip), so I'm thinking between the hotter temps of the day and the motor heating up, there was more vapor in the tank and if it's not venting properly, I was starving the carbs.

Where/how exactly do these 75 Super Sport tanks vent vapor? The gas cap has that hinged lever on the top, but I can't discern any other aspects to the cap that would otherwise vent to atmosphere. There's a small hole on the top of the tank by the filler opening, but I believe that's just for overflow and drains directly under the tank. I replaced the rubber gasket with NOS OEM Honda part and it seems to seal tightly to the tank, but maybe it's too tight? Any guidance from those much more knowledgeable than me would be greatly appreciated!

[SOHC4 Cafe Racer Fan]

Made a couple of maiden runs around the neighborhood and close to home and the bike was running great! Today, I took a little bit of a longer ride to a work event. On the way out, the bike ran great. Good power, response, etc. After the event the bike started right up, but as I was cruising home on a level grade at about 45mph, the power started to roll back. I knew I didn't have a full tank, so I switched to reserve and tried to give it more throttle, but the RPMs just kept slowly winding down until the motor cut off. Pulled over and gave the chassis a shake and could feel fuel in the tank and after a min or two of trying to start, it fired back up. Went back on my way and another mile or so down the road, the same thing happens - power gradually rolls off until the engine cuts off. Happened about 3 times on the way back, but I was able to get home under power with the engine running strong.

I think my gas tank may not be venting properly. Before I left the house yesterday (bike was off and cool) I was in the garage getting ready and noticed an odd sound and traced it back to the gas cap venting vapor. Opening the cap was like taking the lid off a partially full soda. When the motor was cutting out yesterday, I can't remember how many times, but I definitely opened the gas cap at least once to check fuel and it was the same thing - bunch of vapor escaping. There wasn't a ton of fuel in the tank yesterday (maybe 2 gallons to start the trip), so I'm thinking between the hotter temps of the day and the motor heating up, there was more vapor in the tank and if it's not venting properly, I was starving the carbs.

Where/how exactly do these 75 Super Sport tanks vent vapor? The gas cap has that hinged lever on the top, but I can't discern any other aspects to the cap that would otherwise vent to atmosphere. There's a small hole on the top of the tank by the filler opening, but I believe that's just for overflow and drains directly under the tank. I replaced the rubber gasket with NOS OEM Honda part and it seems to seal tightly to the tank, but maybe it's too tight? Any guidance from those much more knowledgeable than me would be greatly appreciated!

I believe the vent on the cap is to facilitate flow down through the petcock. The sound you are hearing when opening the cap is likely air being pulled in versus being pushed out.

[Jooky]

I believe the vent on the cap is to facilitate flow down through the petcock. The sound you are hearing when opening the cap is likely air being pulled in versus being pushed out.

Pretty sure it was vapor escaping the tank, but I'm a complete novice here. It was noticeably more present once the bike sat out in the sun during the afternoon and I opened it while warm.

[SOHC4 Cafe Racer Fan]

I believe the vent on the cap is to facilitate flow down through the petcock. The sound you are hearing when opening the cap is likely air being pulled in versus being pushed out.

Pretty sure it was vapor escaping the tank, but I'm a complete novice here. It was noticeably more present once the bike sat out in the sun during the afternoon and I opened it while warm.

On second thought, I think the vent is designed to also vent pressure.  If it's not doing that, it could be problematic.  If it's not able to allow air in, it might also create a starvation issue.  Just my speculation. 

[Jooky]

On second thought, I think the vent is designed to also vent pressure.  If it's not doing that, it could be problematic.  If it's not able to allow air in, it might also create a starvation issue.  Just my speculation.

Any idea on where the vent is located on these CB 550 Super Sport caps? I did some searching on the forum and from a really old post, it sounded like the cap was designed such that the vapors simply escape up the sides of filler hole and over the top of the rubber gasket. As stated, I purchased a NOS OEM Honda rubber gasket for the cap and the fit is pretty tight, so I don't see how this would otherwise be possible as described.

[Jooky]

Can you post a picture of your cap and filler neck? My recollection is the F model had a fuel lid and screw on cap, not the hinged type cap. I was alway under the impression the hinged was K model cap.

https://www.cmsnl.com/honda-cb550f-super-sport-550-four-1975-cb550fk0-usa_model469/partslist/F++12.html#.WxgNsYopChA

Hey Cal - sorry I may have not described it well. Mine is a screw on cap underneath a hinged fuel lid. Take a look at Page 1 of this thread for a bunch of pictures of the filler neck and cap.

[Jooky]

Yep, definitely an F tank and cap. Did you by chance, fully de-rust that cap? It would have needed an immersion bath and ample flushing to purge and rust/debris from it.

Submerged it in EvapoRust overnight a couple months ago and then washed it out really well. It sat for a while before being installed back on the bike with gas in the tank, so some flash surface rust came back, but nothing like how it was originally. Is there some vent or other vapor escape in that cap that I'm not seeing?

[Jooky]

Meanwhile, I’m trying to decide what medium is most appropriate for the monument I’m building for Cal in tribute. This man is a saint and I greatly appreciate all his time and knowledge. It’s been good hanging out and learning from him both on and off the bike. Thanks Cal!

[flatlander]

Meanwhile, I’m trying to decide what medium is most appropriate for the monument I’m building for Cal in tribute.

stack up a pyramid from a few bottles of gosling's rum 

[Tews19]

New to this build but glad to see the Newbie getting the best help from Cal. Cal is a savior if you get on his good side!

So the shop you took the bike to swapped out jets and idle screws? Did you at least call them up and ask for a refund? Or the old parts from the carbs?

[Jooky]

Fortunately, I had the presence of mind to ask they retain the stock brass after they told me the bike needed this aftermarket kit based on the K&N air filter in the stock air box and the Delkevic exhaust. After picking up the bike from the shop and riding it that day, the pig rich conditions were present (throttle stumbling), I was just too green to recognize them. I called them a day or so later to ask them about it and they did offer to have another look at it, but it was running so poorly I didn't think I could get it over to them. They also took the better part of a month when they "fixed" it before, so I didn't want to end up in another queue. Hence, I started pestering Cal about it and here we are. I will give them a call to explain the situation, but based on not giving them the chance to fix their own mistakes, I'd be surprised if I can haggle any kind of refund. Even if I had taken it back, I seriously doubt they would have gone to all the trouble Cal did to clean and replace the stock brass and get it running properly. An expensive lesson to learn, indeed.

[Jooky]

Full disclosure, the throttle cables and tube were my doing  . However, I have the PO to thank for the clutch cable debacle and odd sized bars 

[Stev-o]

After picking up the bike from the shop and riding it that day, the pig rich conditions were present (throttle stumbling), I was just too green to recognize them. I called them a day or so later to ask them about it and they did offer to have another look at it, but it was running so poorly I didn't think I could get it over to them. They also took the better part of a month when they "fixed" it before, so I didn't want to end up in another queue.

You are better off not bringing it back to them, just chalk it up to a learning experience.
But you should be calling them back and talk to the owner or service manager and let him know what a botched job they did and you will no longer bring your bike there [and tell your buddies not to either]

[Jooky]

Sadly, they are one and the same. It’s a family run business and the people themselves are quite nice. I’m somewhat surprised they goofed this up so badly, as they have photos in the front office of another CB they restored that won some awards. Maybe it didn’t run?