Topic: Cam chain - how do I know it got adjusted?

[mikethejeepguy]

I've read countless instructions on how to adjust the cam chain on my CB550F, and now that I finally ground off the overtightened nut (courtesy of the PO) I adjusted it. At least I hope I did. at 15 deg past TDC on #1 (valves loose) loosened nut, took screw driver twisted what seemed 1/8 of a turn clockwise and felt spring-like resistance, then turned it back, held in place and tightened the new nut. Didn't hear a click or feel anything... kind of uneventful really. I still have noise at idle, but that might be my carbs out of synch.  The screw only turns clockwise kind of loosely until there is a springy resistance for about 45deg turn of the screwdriver. The screwdriver then returns, but will not turn much counter-clockwise.

The bike is a 76 CB550F, and has 23,000 miles on it (am hoping that the motor is original, but one can never be sure).

How do I know the cam chain is adjusted? Did I do it correctly? Also, how can I tell if the tensioner is at the end of it's adjustment/life?

Any input is appreciated. Sorry to beat a dead horse, but I can't seem to find the answer anywhere.

Mike

[Scrubs]

As far as knowing for definite whether it has worked - I wouldent know how to tell without taking the head off.
But I can tell you that it is a pretty uneventful adjustment - at least whenever I have performed it.


Did you back the screw out (anti-clockwise) first before you screwed it in?


Heres how I do it:

Loosen locknut, then turn adjuster screw a half turn anti clockwise, then turn it clockwise till you can just begin to feel it nipping up. tighten locknut.

[mikethejeepguy]

Hey Scrubs, Thanks for the reply. I will be tackling your gauge faces shortly, I've had a lot on my plate with graphics, work, and bike but am hoping this week I'll do something with that.

It didn't seem like the screw wanted to turn counter-clockwise, maybe a tiny bit, but not likely a half turn. It would only turn clock wise almost a 1/4 turn, where I felt a resistance that seemed like from a spring. I figured that it has adjusted and let it return to it's "normal" position before tightening it.  I guess I did that wrong? It seems like there is a lot of info on CB750 adjustment, but I wonder if it is different from the 550? I must have read the Honda Service Manual 20 times.

Maybe I'm just stoooopid 

[Scrubs]

Hi Mike, You could well be right, It might be different for the 550 - Lets wait for someone else to chime in to be sure.
Great news about the gauges , Thanks, whenever you get the time will be fab!. 

[Scrubs]

Just had a little read of a CB500 manual and the bit that says turn it clockwise and not anti.
But I did notice that I read that in the 'dissasembly chapter' for If you intended to remove the chain,
because beneath that it says "in this condition the tensionor is not applying tension to te cam chain"


I could well be wrong, I would be very surprised if I wasent for a change so best dbl check with someone in the know  

[mikethejeepguy]

Thanks buddy! Maybe I'll re-read the manual. This is my first time adjusting it and perhaps I'm making more out of it then I should. I know this is supposed to be a basic thing, so why am I so perplexed? Any 550 owners have any more info?

[bryanj]

Keep youre screwdriver out of that slot AT ALL TIMES unless dissassembling the motor!!!!

[mikethejeepguy]

Please excuse my stuuupidity.... so just loosen the nut, let the "magic" happen, and tighten the nut, only using the screwdriver slot to hold the peg in place?    No twisting of the peg required?

[Hush]

Mike, if you haven't yet had carb sync you will see jack all change to engine noise, cam chain noise and out of sync carbs are about the same.
You may have done a perfect job readjusting the cam chain but you wont know until sync done.

[City Boy]

Hi.You can check that cam chain is adjusted correctly without engine running.Remove one tappet cover and turn engine untill the exposed rocker starts to open the valve.At this point move the crankshaft a little in each direction while observing the rocker.The rocker should move at the same instant that the crank is moved.If there is any delay,there is still slack in the chain.  Rock On

[TwoTired]

The adjuster mechanism is spring loaded.  The spring creates the proper tension on the cam chain adjuster shoe against the chain.  Once you position the engine and crankshaft so that the slack part of the chain is on the adjuster side (15 degrees) then you loosen the jam nut holding the shoe in a fixed position.  The spring can move the shoe out into the slack chain and remove the slack.  Re-tighten the jam nut and the shoe is now held in the new position so the chain won't flop around.

Twisting the "screw slot" (it's not a really a screw) simply works against the tension spring.  It should spring back on it's own.  The screw slot is NOT necessary for proper cam chain tension.  It isn't even needed for adjustment operation.  The slot does come in handy when you wish to move the shoe away from the chain as far as possible, like when you wish to the remove the cam sprocket from the cam, so you can remove the cam from the head.

Now you know why the Honda procedure doesn't mention a screwdriver in the stud slot on pgs. 12 and 13 of the Honda shop manual.

Cheers,

[seaweb11]

Slight hijack. but still related

TT did you read my recent cam chain tightening  thread? 
http://forums.sohc4.net/index.php?topic=51860.0

[TwoTired]

Slight hijack. but still related

TT did you read my recent cam chain tightening  thread? 
http://forums.sohc4.net/index.php?topic=51860.0

No, I didn't before now. 
But, do you know that the 550 cam chain tensioner works differently than the 750?  The 550 is adjusted statically with the slack side of the chain on the adjuster shoe side.  This is why the special position of he crank shaft, so that the cam lobes and valve springs hold the chain slack on the shoe side.

Changing the cam profile would also require an amendment to a static cam chain adjustment procedure.  If you are increasing the valve spring strength, it stands to reason the adjuster spring strength may need to be changed as well for a static adjustment.
Stiffer valve springs and a more radical profile cam, can easily place more stress on a cam chain.  If you are adjusting the tensioner with the engine running, you may have to modify standard procedure to accommodate other changes made to the engine.

Just an observation.  Things needed for a race engine are somewhat different than things needed for a street engine or one operated within manufacturer parameters.  Not all special needs apply to the street.  One of the early lessons in engineering is that changing one thing in a design often effects other things in the overall design.  It's the ripple effect.  Which sometime resembles the "whack-a-mole" game.

Cheers,

[mikethejeepguy]

Guys, thanks SO much for all the info. I really appreciate you taking the time to explain something that is totaly mundane to most of you, but confusing to a newb.

Re: Carb sinch.. I pulled the bowls off my carbs the other night, and the o-rings on my mains are so shrunk that as soon as I take off the bowls, the main jets fall out. Luckily I'm in the process of rebuilding an other rack of carbs which I hope to sink with a Morgan Carbtune tomorrow. I figure no sense of tinkering with the ones that are on the bike right now. It would be AMAZING if the tick would go away with synched carbs. Keeping my fingers crossed.

Thanks again! you guys rock as always!

[TwoTired]

I hope you still have the spring leaf retainers for those mains.  The jets are retained by those, not the orings.  The orings just provide a seal.

Do get new orings, as the seal they provide is important for a well tuned carburettor.

Cheers,

[mikethejeepguy]

Thanks TT!

Yup have all the parts in separate coffee cups, cleaned and ready to go back in, and I will replace all o-rings. Hopefully the new carbs will be good as new when I'm done I hope I get to post on how smooooth everything is running soon. I have a feeling much of the engine clunk is caused by crappy carbs. As per your suggestion in one of my previous posts (last year) it is amazing how a simple tune up smooths things out. This is my last chore on that tune-up list. Am also sticking to your advice as how to set these carbs up (K - needles with stock clip setting and 100 mains) on my 550F due to my pipe. I also think my bike is much happier with the UNI filter..... I think this week will be dedicated to plug chops.