Topic: Oil Change 76 CB550 Four & recommended tire pressure - Nube questions I know.

[KevinD]

Just wanted to start off with the point that I did do a search on this and found nothing concerning ideals for this.  I am sure it has been addressed 1000 times but I could not find the info on here.  Seems like a pretty simple situation.  I just picked up a CB550 Four and checked the oil and it is far from clean and just figured I'd get this dialed in.  I ordered a filter with the two O rings that are needed.  Here is my question.  I have heard that synthetic oil is not ideal for these.  I live in AZ and will be on the higher temp area and wanted to know what is the best weight oil for AZ conditions I will be riding all year around so it will get to a arctic temp out here of around 60 degrees in the winter just wanted to see if anyone recommends a specific type of oil for these 550's .  Also any tips that may not be obvious would be appreciated.  I also noticed that I was riding with WAY underinflated tire pressure (No Brady references needed) but obviously it was causing handling issues.  I am running Kenda Challenger tires and could not find ideal tire pressure as well.  I am about 180 lbs if that makes any difference.  Want to be safe for myself and bike.  Thanks in advance for any info and your patience on some simple questions!!

[ofreen]

Any quality 10w40 or 20w50 motorcycle oil will do. Your engine may start to weep a little from various places when using synthetic. It may weep anyway no matter what you use.

Find the manufacturer's maximum load rating and inflation on tire sidewall. Subtract 10%, start there and see how it feels when riding.

[dhall57]

Welcome. Had a 1976 CB550 back in the day and wish I had held on to it. They are nice bikes. Since getting back into these old Honda's in 2009 I always ran 10w40 in my all my CB750's but last few years switched up to 20W50. Either weight should be fine . I have never used synthetic oil.   Generally I keep my tire pressure 32 to 34 front and 34 to 36 rear range.

[Whaleman]

Tire pressure has to do with the tire and not the bike. It is wrong to look in a 40+ year old owners manual to see what the tire pressure should be for modern tires. The advice given about the max minus 10% is a great place to start. It WILL be higher than you thought. Dan

[KevinD]

I checked the sidewall before posting on here and could not find anything.  This morning I went back out with a flashlight and found max load info at 40 psi.  I guess that is it, so I'm at 36 psi.  I switched the tubes and tires out at a local shot a couple weeks ago and after a squirly ride found that I was riding on 10 front and 12 rear psi.

[Mooshie]

 I too have a 550.  I use 20/50 oil.  Just make certain no detergent in there.  I live in CA and have ridden my bike all around and I really like that weight oil. For my tires I run 36 front and 40 rear.  I have Avon Roadrunners.

[dhall57]

Hey Mooshie how you been. Wouldn't mind someday getting another CB550. Really like those bikes How's everything across the country in Ca. Rode much this summer.

[Duanob]

I checked the sidewall before posting on here and could not find anything.  This morning I went back out with a flashlight and found max load info at 40 psi.  I guess that is it, so I'm at 36 psi.  I switched the tubes and tires out at a local shot a couple weeks ago and after a squirly ride found that I was riding on 10 front and 12 rear psi.

The shop let the tires go out the door like that? I would find a new shop after that.

[BobbyR]

I would use the Max -10% as a starting point. The modern tires have a different sidewall construction which will vary by manufacturer.  Play with the pressures until the bike responds to your liking. As you found out, they get squishy at lower pressures. Even at the recommended owners manual pressures the bikes usually feel "heavy" and unresponsive.   

[KevinD]

Sorry, I have missed checking this page in a couple weeks.  Yeah, the tire shop most likely put the tires out at the correct pressure and supposedly new tubes.  One thing I am noticing is that I have a slow leak in both tires.  I filled them up in the mid 30’s psi range and in the last week and a half they are down to mid 20’s psi range.  Very bizarre.  That really does not seem normal.  Someone I work with was telling me I should do some nitrogen fills to keep the pressure consistent over a longer period of time.  I was thinking about a portable inflator.  Any thoughts?  Thanks for the responses as well.  Oh yeah, until the weather gets under the 105 and up range I am really just doing weekend morning runs. 

[flatlander]

you may just need to tighten the valves. they are screwed into that "stem" that sticks out of the tube.
when you buy your own tubes tbere is usually a little piece on top of the valve that is often just discarded and replaced with the cap. it has a little nozzle with a slot in it that fits into the "stem" and can be used to screw down the valve. if you dont have this thing just ask in a bike or tire shop.

[70CB750]

Sorry, I have missed checking this page in a couple weeks.  Yeah, the tire shop most likely put the tires out at the correct pressure and supposedly new tubes.  One thing I am noticing is that I have a slow leak in both tires.  I filled them up in the mid 30’s psi range and in the last week and a half they are down to mid 20’s psi range.  Very bizarre.  That really does not seem normal.  Someone I work with was telling me I should do some nitrogen fills to keep the pressure consistent over a longer period of time.  I was thinking about a portable inflator.  Any thoughts?  Thanks for the responses as well.  Oh yeah, until the weather gets under the 105 and up range I am really just doing weekend morning runs.

Something is wrong, the tire/tube should hold pressure for month or more.  Check your valves.

Try this:  measure pressure first thing in the morning, take her for a spin and measure again.  Correctly filled tire will have pressure go up +/- 2psi.

[Johnie]

I was running my first set of Conti's about 34-36 and the center of the back tire wore a lot faster in the center. Now I am trying around 28 - 30 front and 30 - 32 back. I will see what I get for wear.

[edwardmorris]

What kinda tubes are you using? I was told that rubber tubes like the Metzelers I use will need to be inflated a lot more often than other kinds as they don't hold up pressure for long intervals. But the advantage is that they won't explode when you stick a nail in them, they'll slowly weep out. With the Metzelers and Conti's, I use 28-30 front and 30-32 rear much like Johnie and it tends to lose a good amount in about 10 days of on and off riding for me.

[Johnie]

I do check my pressures before every ride like Ed. And they do need a sip of air each time.

[BobbyR]

What kinda tubes are you using? I was told that rubber tubes like the Metzelers I use will need to be inflated a lot more often than other kinds as they don't hold up pressure for long intervals. But the advantage is that they won't explode when you stick a nail in them, they'll slowly weep out. With the Metzelers and Conti's, I use 28-30 front and 30-32 rear much like Johnie and it tends to lose a good amount in about 10 days of on and off riding for me.

That is true, the natural rubber is more porous than the synthetic. It is also thicker. I have ben using them for years. You will find they need a small shot of air every few weeks.

[PeWe]

CB750: My tires get the pressure according to the Honda label, still not applied on rear fender:) I prefer BAR when I'm used to it.
Front:2.0 BAR (28 PSI) Rear: 2.1 BAR (30 PSI)
High speed: 2.2 BAR (32 PSI) 2.4 BAR (34 PSI)
 Newer tires, Dunlop Streetsmart. I do not Think the pressure spec is different than my old tires I used during the 80's. Still not radial.
Around 2.0-2.3 BAR. (29-33 PSI) . 2.5 Bar (36 PSI) was too hard on my bike not comfortable, especially front wheel that cause pain in my hands.