Topic: '74 cb550 ... Noisy cam chain, eh?

[Stev-o]

Sounds like she is idleing pretty low also.. It should be at 1000 rpm
.: Scott :.

Seriously, only 1000? I have mine set at about 1500 at the suggestion of a buddy who is a certified bike mechanic.

[Zaipai]

Sounds like she is idleing pretty low also.. It should be at 1000 rpm
.: Scott :.

Seriously, only 1000? I have mine set at about 1500 at the suggestion of a buddy who is a certified bike mechanic.

Actually I got that from the Clymer manual, it says to set it between 1,000 and 1,200 so.. I don't know for sure, however in the video it seemed kinda low either way..

.: Scott :.

[traveler]

my 550 seems to "like" 1,200 RPM.....FWIW.

~Joe

[Zaipai]

my 550 seems to "like" 1,200 RPM.....FWIW.

~Joe

Yea mine too.. However I have heard them run VERY nice at 1,300 and 1,500 I am not sure why that is..

(Sorry to have sudo hijacked the thread... Back to your sounds..)

.: Scott :.

[75cb550 (kyle)]

Sounds like she is idleing pretty low also.. It should be at 1000 rpm
.: Scott :.

Seriously, only 1000? I have mine set at about 1500 at the suggestion of a buddy who is a certified bike mechanic.

Actually I got that from the Clymer manual, it says to set it between 1,000 and 1,200 so.. I don't know for sure, however in the video it seemed kinda low either way..

.: Scott :.

i think my tach must be off...

[cb544]

Sounds like she is idleing pretty low also.. It should be at 1000 rpm
.: Scott :.

Seriously, only 1000? I have mine set at about 1500 at the suggestion of a buddy who is a certified bike mechanic.

Actually I got that from the Clymer manual, it says to set it between 1,000 and 1,200 so.. I don't know for sure, however in the video it seemed kinda low either way..

.: Scott :.

i think my tach must be off...

It's definitely idling low... and sounds fine at around 1200-1500. Of course, maybe my tach is off too. Assuming it's accurate, do I adjust each carb's idle screw or a shared linkage? The throttle is actually engaged at idle, so the 10-15 degrees of play the manual calls for is not the case... I assume if I gave it that play, it wouldn't idle at all. Is that just clogged jets? This is actually my first experience with carbs...

[cb544]

(Sorry to have sudo hijacked the thread... Back to your sounds..)

.: Scott :.

No way Scott- this is exactly what I need to be thinking about. :-D Cheers!

[Zaipai]

I would start by getting the bike good and warm and let it fall to idle. Then adjust the idle screw that is on the right side, big thing brass I think.. I am pretty sure its the linkage idle screw, tho I am not completely sure.

See how that works. If you can not get a successful idle that way then you may wish to adjust the cabs.. Just my 2 cents tho..

.: Scott :.

[cb544]

I would start by getting the bike good and warm and let it fall to idle. Then adjust the idle screw that is on the right side, big thing brass I think.. I am pretty sure its the linkage idle screw, tho I am not completely sure.

See how that works. If you can not get a successful idle that way then you may wish to adjust the cabs.. Just my 2 cents tho..

.: Scott :.

Do you ever feel as if your CB is mocking you? Maybe I just need to shave...

My cam chain tensioner will not adjust (the screw clicks and clicks, so I assume that gear drive is broken inside). Can I replace it with the motor inside the bike? I've read that SOHC Fours are notorious for cam chain slap at idle if the carbs aren't synced right... I've also heard it could be the primary chain, or the clutch, but I think these are all pipe dreams to cover up the denial of needed to replace the cam chain and tensioner. Is there an updated tensioner that I can rely on?

Also, the carbs leak fuel (I'm talking WASTE fuel) out the overflow hoses... what does this mean?


Ahhhh, I love this bike but I really need to fix this before I go further and can justify even replacing the tires (or at least putting tubes in them!), not to mention sorting out that fuel tank that's sitting on the couch!

[Zaipai]

I am not sure about the tensioner, sounds like it needs to be replaced. As far as the carbs leaking goes, if the gas is coming out the tubes its likely your floats are adjusted incorrectly. That is a pretty easy fix.

There is a great read on these carbs and getting them sync'd correctly float levels etc..

http://forums.sohc4.net/index.php?topic=5410.0

Also check out the FAQ's section lots if good stuff there on CB500/CB550's ...

And yes, I feel Mocked, every time I say lets go for a ride, and my bike says only if I am in the mood today! 

.: Scott :.

[cb544]

And yes, I feel Mocked, every time I say lets go for a ride, and my bike says only if I am in the mood today! 

.: Scott :.

Haha, cheers to that!

[RAFster122s]

Gonna have to disagree with the assessment of incorrectly adjusted floats, it is a sign of the float needle not seating allowing the fuel to overflow...that means dirty carbs.
New seals and clean everything spotless and ensure you have clear jets for all three jets and your carbs are adjusted so the floats are set to spec.
Once you have it running smoothly and not puking gas everywhere, then you can tell if you have cam chain slapping noises or primary chain or otherwise.

Be careful with old tires, false economy just changing tubes, since the hardened rubber won't grip you are likely to have an accident causing more expense than spending one to two hundred on new tires, tubes, and rim strips.

Download the shop manuals on the 550 and start reading to educate yourself on the work ahead.

David

[Zaipai]

Yea, listen to RAFster122S.. When it happened to me it was float hight, however that my not be your issue and I am some thing of a novice at this so..

.: Scott :.

[cb544]

Gonna have to disagree with the assessment of incorrectly adjusted floats, it is a sign of the float needle not seating allowing the fuel to overflow...that means dirty carbs.
New seals and clean everything spotless and ensure you have clear jets for all three jets and your carbs are adjusted so the floats are set to spec.
Once you have it running smoothly and not puking gas everywhere, then you can tell if you have cam chain slapping noises or primary chain or otherwise.

Be careful with old tires, false economy just changing tubes, since the hardened rubber won't grip you are likely to have an accident causing more expense than spending one to two hundred on new tires, tubes, and rim strips.

Download the shop manuals on the 550 and start reading to educate yourself on the work ahead.

David

Very good advice, thanks David- I will certainly replace the tires, and will start pulling apart the carbs.. I have a lawnmower that does the same thing only it puts the fuel into the air filter. If you can see me thru the tall grass, come give me a hand!

[Zaipai]

Ah.. you need this mower!!!

http://www.youtube.com/user/aapont#p/a/u/1/VPeXW41dj44

.: Scott :.

[cb544]

Ah.. you need this mower!!!

http://www.youtube.com/user/aapont#p/a/u/1/VPeXW41dj44

.: Scott :.

  Wow. I've never seen anything like that before... Nice little hot rod

[cb544]

I envy all of you with a real garage space...


Well, after melting the inlet of the fuel filter and thus blocking the passage of fuel, I've moved onto other things. I realized that there is way too much slack in the drive chain, and adjusting the tension doesn't solve the problem. It simply looks dangerous anyways, so I've taken off the rear wheel and on my way to get beer stopped at the gas station to see if they couldn't put some air in the tire. Well, they couldn't. For some reason the valve is not letting air thru... anyone else ever experience this?




In other news, I've run some fuel through the new/old/used tank you see on there and there really wasn't that much being stopped at the fuel filter. I'm ready to buy the real deal (brass fittings and a metal encased fuel filter, preferably cleanable/replaceable) Anybody know what I'm talking about?



Lastly, I think it's safe to say the carbs need a cleaning, and I need a new chain, tires, maybe a cam chain tensioner... one thing at a time... but what do you think about the rear sprocket? Looks like it needs to be cleaned and greased, but otherwise can be reused.



On a brighter note, I got the seat pan back on. I sorta like this "ball sling" sorta saddle I've got in the works. As long as it clears the tank for now.. and it comes with sharp rivets! (If it doesn't hurt, don't do it. )

[75cb550 (kyle)]

something like this? its a glass tube that threads together. it kept air locking my system so i took it off

[75cb550 (kyle)]

sorry for the poor pic quality, by the way.

[cb544]

something like this? its a glass tube that threads together. it kept air locking my system so i took it off

Hmm, just like that... maybe I should run without a filter? The tank petcock doesn't seem to have one... only a long tube which would presumably keep the intake up off the floor of the tank avoiding most contaminants.

[75cb550 (kyle)]

there's a very long thread about that, probably several actually. from what i can tell, the general consensus is the petcock should have a filter/screen in it anyway. i like to run an inline filter so i can see fuel level coming of tank and just for the extra measure of safety. if your petcock does not have one, then i would definately run one. it does not take much to hang out a float needle. my .02.

[tonycb650]

that noise you hear is clutch rattle.

[Zaipai]

Sure looks like you have your work cut out for you. Like you said one thing at a time. It will go fast you watch. On my tank, I have a screen around that tube, so perhaps you do need an in line filter. That rear sprocket is in bad shape however cleaning up should be ok. Chain is a must, so a new one is always good, don't want that sucker snapping off on the highway.

.: Scott :.

[cb544]

Well I'll tell ya, it sure is nice to have to time to go around and hammer out a few dents in the shiny stuff... straightened the fenders, the gauge rings... got the fuel tank hooked up temporarily and although it idles I've surely got some cleaning to do. Still pukes fuel out the overflows and has those noises, but I did replace the valve cores and got some air in the tires! It's the little, unrelated victories that count!  ... My brother said he had a float in his single cylinder Honda (maybe a CL25?) with a hole in it, and produced the same effect... any thoughts on that?

Just a few pics to keep you interested...

[Zaipai]

Nice, throw a seat on it and fix the carb problem and ride it the rest of the summer, then worry about the clean up part.. 

You are sure making progress none the less, and you are correct its the little victories!

.: Scott :.