Author Topic: Manual Cam chain adjuster (Read 7993 times)

Johnny5 · « **Reply #25 on:** February 17, 2009, 10:37:27 AM »

I would venture to say if you hear zero cam chain noise, then you're in for some problems. A little bit of noise is normal. A lot of noise isnt good...

One of those lines you want to be in the happy-medium.

UnCrash · « **Reply #26 on:** February 17, 2009, 11:58:49 AM »

Quote

I am a bit slow. Now do I unbolt the whole assembly to put presure on the spring. I can see no way to do it otherwise.

Bobby - the screw (going up) into the adjuster rod just needs to be unscrewed. When I unscrewed mine I could tell that the rod didn't budge. I then knew that there was so much crud in there that I would have to pull it off. The rod is steel and the adjuster housing is aluminum which doesn't help...

Anyway after I took the unit off the engine and disassembled and lubed it up I felt that the spring had seen better days. So I positioned #1 as the instructions say and loosened the screw, then with a right angle end screw driver pushed the rod in just a little, then tightened up the screw.

It did help!

BobbyR · « **Reply #27 on:** February 17, 2009, 12:06:18 PM »

Quote from: BobbyR on February 17, 2009, 08:20:48 AM

Quote from: UnCrash on February 16, 2009, 05:42:18 PM
My cam chain is particularly noisy on my 78F. My best results (after disassembling, cleaning, and lubricating the tensioner) was to position #1 as recommended in the shop repair manual, loosen the lock screw, then take an 90degree angled screw driver and gently give an extra push to the plunger, tighten down the lock screw...

I am a bit slow. Now do I unbolt the whole assembly to put presure on the spring. I can see no way to do it otherwise.

DO I need to unbolt the adjuster assembly and push the spring? Or, od I take out the adjuster bolt on the bottom and put something angled in there to work the mechanism?

cafe750 · « **Reply #28 on:** February 17, 2009, 01:06:22 PM »

Quote from: BobbyR on February 17, 2009, 12:06:18 PM

Quote from: BobbyR on February 17, 2009, 08:20:48 AM
Quote from: UnCrash on February 16, 2009, 05:42:18 PM
My cam chain is particularly noisy on my 78F. My best results (after disassembling, cleaning, and lubricating the tensioner) was to position #1 as recommended in the shop repair manual, loosen the lock screw, then take an 90degree angled screw driver and gently give an extra push to the plunger, tighten down the lock screw...

I am a bit slow. Now do I unbolt the whole assembly to put presure on the spring. I can see no way to do it otherwise.

DO I need to unbolt the adjuster assembly and push the spring? Or, od I take out the adjuster bolt on the bottom and put something angled in there to work the mechanism?

Just loosen the lockscrew, and use some sort of implement to push on the end of the rod, in the hole in the end of the tensioner...No unbolting necessary.

BobbyR · « **Reply #29 on:** February 17, 2009, 01:11:58 PM »

Thank you boys I am now a happy man. I have to dop the bottom of the airbox to replace the filter which will give me more room to play with it.

UnCrash · « **Reply #30 on:** February 17, 2009, 01:14:21 PM »

Quote

Thank you boys I am now a happy man. I have to dop the bottom of the airbox to replace the filter which will give me more room to play with it.

Yep, that will help.

Just find an old phillips head screwdriver and bend the end 60 degrees. I have found many uses for this "tool"

sandcastcb750 · « **Reply #31 on:** February 17, 2009, 01:48:13 PM »

Rotate the engine backwards, then the slack is in the back and the cam tensioner spring will push it in.

BobbyR · « **Reply #32 on:** February 17, 2009, 02:36:30 PM »

Thanks fellas, I will give it a shot this weekend.

Markcb750 · « **Reply #33 on:** February 17, 2009, 04:20:37 PM »

Quote from: sandcastcb750 on February 17, 2009, 01:48:13 PM

Rotate the engine backwards, then the slack is in the back and the cam tensioner spring will push it in.

isn't the system designed so that the tensioner is on the slack side in normal operation?

Not so sure winding it backward would help the spring set the proper tension on the chain.

Quote from: Johnny5 on February 17, 2009, 10:37:27 AM

I would venture to say if you hear zero cam chain noise, then you're in for some problems. A little bit of noise is normal. A lot of noise isnt good...

One of those lines you want to be in the happy-medium.

This is "sound" advice!

mystic_1 · « **Reply #34 on:** February 17, 2009, 04:33:24 PM »

Quote from: Markcb750 on February 17, 2009, 04:20:37 PM

isn't the system designed so that the tensioner is on the slack side in normal operation?

Correct! Normally, the crankshaft rotates clockwise, as viewed from the points-cover-end. This pulls downward on the front run of the camchain, taking up slack. The slack is then all on the rear run of the camchain, which is where the tensioner is located. This is why it's important to rotate the crankshaft as described in the manual, and why it's so important to not let the crankshaft rotate backwards AT ALL once you've got it positioned. If the crankshaft starts to rotate backwards (counterclockwise when viewed as described above), it will take up slack from the rear run of the camchain and the front run will become slack.

Wish I could find a simple diagram of this, a picture is worth 1000 words.

When I do my camchain adjustment on my 750, I like to continue to apply light pressure on the crankshaft once I have it positioned at 15°ATDC, to make sure all the slack stays on the rear run of of the chain. You can then use your other hand to loosen the locknut on the tensioner, and if necessary use your third hand to apply pressure to the tensioner rod

mystic_1

sandcastcb750 · « **Reply #35 on:** February 18, 2009, 11:20:16 AM »

Maybe the manual is wrong. Or, doesn't explain it well.

All I know is, that the slack of the tensioner is taken up at the rear. If you rotate it foward, it will be tight against the tensioner and push the tensioner out, as you don't want. The back side will be tight and the tensioner in the wrong position, too far out.

I did it as you advise, once, and the cam chain rattled.

BobbyR · « **Reply #36 on:** February 18, 2009, 02:15:10 PM »

Hmmmmmmmmm the plot thickens. The forum pornographer is now more confused than ever.

cafe750 · « **Reply #37 on:** February 18, 2009, 03:24:39 PM »

Quote from: BobbyR on February 18, 2009, 02:15:10 PM

Hmmmmmmmmm the plot thickens. The forum pornographer is now more confused than ever.

speaking of which, how do I go about seeing the rest of the girl in your avatar? I think she is the best yet....

Krixxer · « **Reply #38 on:** February 18, 2009, 04:04:30 PM »

How is it the they never bothered to change this set-up?Honda is notorious for this but I didn't realize they had this problem for over 30 years now.

I've installed manual adjusters in a friends F4i and 600rr ....30 years....10k bikes... and you still get the same old gremlins.

NitroHunter · « **Reply #39 on:** February 18, 2009, 04:19:08 PM »

Something else to look at, is the adjuster gouged where the lock bolt contacts it? A burr here can stop the adjusters movement to where the spring can't do it's job. Also, if the lock bolt tries to recenter into the divot, this can pull the adjuster back into it's previous location.

TheHun · « **Reply #40 on:** February 18, 2009, 06:55:12 PM »

I did as the manual says..and it pushed back my tensioner and started to make a weird sound I was like W T F mate...so I pushed the tensioner back with a bolt until the noise disappeared and bolted it back. No more noise

mystic_1 · « **Reply #41 on:** February 18, 2009, 08:41:42 PM »

Were you adjusting it with the bike running? I know that some manuals say to do it that way. Don't.

Instead, use the procedure in Honda Service Bulletin CB750-19:

http://sohc4.com/tiki-download_file.php?fileId=14

Quote

1. Remove the tappet covers from the #1 cylinder.

2. Remove the point cover, and use a 23mm box wrench to rotate the crankshaft to the "T" position for cylinders #1 and 4 (1.4).

3. Check both valves of #1 cylinder. If both valves are free, proceed to next step; if either or both of the valves are tight, rotate the crankshaft 360°, then proceed with the next step.

4. Rotate the crankshaft clockwise until the spring peg of the advancer assembly at the 1.4 position is just to the right of a line from the timing index (see Fig. 1). This position is 15° ATDC 1.4.*

5. Loosen the cam chain tensioner lock nut, and back out the setting screw until the tensioner arm is released and moves in to take up the slack.

Note: The tensioner is automatic. Do not use additional pressure to move the tensioner arm.

6. Retighten the setting screw and lock nut, re-install point cover and tappet covers.

* At this point, the slack in the cam chain will be on the tensioner side, thus assuring effective tensioner operation.

mystic_1

bryanj · « **Reply #42 on:** February 19, 2009, 09:39:01 AM »

Turning the enging in the direction of motion I.E. CLOCKWISE at the points end DOES NOT push the tensioner back it allows the tensioner to work!!!

IT DOES NOT MATER A STUFF where the crank is set as long as you have the crank just about to rotate in the running direction so that the front run of camchain is tight and this works for ALL hondas.

It is a good point that the adjusting bolt will try and re-centre into any mark in the adjusting rod ALSO when the camchain is worn out the lip at the end of the adjuster stops the rod moving any farther in to take up play. It is a good indication of chain wear to remove the tensioner assembly complete end see how much movement the plunger has left when the pinch bolt is loosened

bryanj · « **Reply #43 on:** February 19, 2009, 09:51:24 AM »

I new it was written out before.

having gone to the FAQ's and engine and searhed cam chain i can up with

http://forums.sohc4.net/index.php?topic=369.msg315851#msg315851

which is what i wrote some time ago.

So my point is

PLEASE CHECK THE FAQ'S

Markcb750 · « **Reply #44 on:** February 19, 2009, 01:14:45 PM »

Quote from: bryanj on February 19, 2009, 09:51:24 AM

I new it was written out before.

having gone to the FAQ's and engine and searhed cam chain i can up with

http://forums.sohc4.net/index.php?topic=369.msg315851#msg315851

which is what i wrote some time ago.

So my point is

PLEASE CHECK THE FAQ'S

No offense but I did that, and dispite several reviews of the answers returned to manual cam chain adjustment, cam chain, screw type cam chain adjustment I saw nothing that answered my question.

MY Point is, don't assume the poster did not check the FAQ's

Markcb750 · « **Reply #45 on:** March 02, 2009, 05:05:21 AM »

[youtube=425,350]iOQWtcrdrV0&feature=related[/youtube]

The engine noise of this 750 at about the 1:00 time mark is the noise mine makes. Normal I hope?

sandcastcb750 · « **Reply #46 on:** March 05, 2009, 06:38:56 AM »

Since you mentioned slack, the slack is in front of the pulley in the direction of movement.

Draw it and look at it.

Markcb750 · « **Reply #47 on:** March 05, 2009, 03:59:41 PM »

the crank runs Clockwise at the grank shaft...

sandcastcb750 · « **Reply #48 on:** March 10, 2009, 08:09:13 AM »

In front of the direction of movement, NOT the engine.

Think of a long train half over and half behind the crest of a hill. The back end before the hill is tight and the front half past the crest of the hill is slack. Now relate that to a chain on a pulley.

MCRider · « **Reply #49 on:** March 10, 2009, 08:34:27 AM »

Quote from: bryanj on February 19, 2009, 09:39:01 AM

Turning the enging in the direction of motion I.E. CLOCKWISE at the points end DOES NOT push the tensioner back it allows the tensioner to work!!!

IT DOES NOT MATER A STUFF where the crank is set as long as you have the crank just about to rotate in the running direction so that the front run of camchain is tight and this works for ALL hondas.

SNIP

I'll have to take issue with that. It does matter. That is because at certain points in the rotation, the valve spring tension on the cam is pushing the cam forward, and some slack is transferred to the front run. At the point in the service bulletin, the valve springs are holding the cam back putting all the tension in the front and all the slack in the back.

Your basic idea is correct, the point in the service bulletin is more correct.

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Author Topic: Manual Cam chain adjuster (Read 7993 times)

Markcb750

Krixxer

Markcb750

Markcb750

Markcb750