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I'm following your postings with much interest and appreciate you taking the time to post them.
I presently have the head off of my 954 because four of the exhaust valves on cyclinders 1 and 3 were burnt. As a result compression tests were 55, 176, 60 and 176 on cyclinders 1 thru 4. Just replaces all the exhaust valves and lapped all valves waiting for new valve seals since everything is torn apart and the bike has over 46k miles.
I just want to confirm the cam timing fingers on the end of the exhaust valves appear in the correct position and are not potentially flipped around.
Simply laid the cams into the prescribed position, laid a metal ruler over the cam lobes as you did then measured 15mm from the bottom of the ruler to the head surface on each lobe.
Appears to me you are on the right track. I didn't find a spec for the cam chain length to determine if it is worn excessively. If you have one or the Honda fellow knows what it should be then that information is helpful as well.
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Discussion Starter · #22 ·
I laid my old cylinder head out with the cams in there positions and went of there cam lobe positions and took pictures so I can go back and see what mine actually look like on the bike and bolted down. Mine does in fact look lime it's 1 tooth off on the intake side but it's actually not, it can't be for that matter, it has got me stumped and frustrated, I must have took then off and put then on in so many times and everytime there left in the exact position time and time again. Now I know there right because I have counted the links from exhaust cam to intake cam and from my understanding you could 15 double links basically copying the picture in the manual. My chain rests on the same links. Now if I did lift.my intake cam up higher as right nows it lower that the head! It would then be higher than the head and off set from the exhaust cam and the fact it would then be on 14 double links and not the 15 shown. I do remember having this problem 4 years ago when I blew 2 exhaust valves and had to do the rebuild myself and I remember then it wouldn't line up too.i always assumed I was 1 tooth off but the bike ran,and it ran great.....but in the back of my mind I always thought if it was truly level would I gain a bit more power. Not sure if this bikes advanced on the timing or regards when everything lines up the way they say to. Weirdly enough mine always line up perfectly level when my timing mark is on the T and not the (I) even though I do line them up when the marking are set. It just never stays were I set it after a few revelations of the engine. Now 1 tooth is enough of a difference to see that your off on the intake and exhaust cam lobes when you look at them closely. Weirdly enough if I was to literally take the cam chain tensioner and pull the plunger in and losen all the cam holders so there just resting on the cams and all come up level.....Guess what! Intake and exhaust cam markings are then level with the head, which then got me thinking whether the intake cam was rolling back a little when I was bolting them down causing the undeveloped markings on the cam to head. I did try that yesterday by holding intake cam.in position and kind of pulling the intake 1 cam lobe up while slowly getting them bolted nice and square. Looked bang on.....but again as soon as I started to rotate the engine by hand a few revolutions, they would end up exactly where they always end up.........intake lower than head and exhaust a little.higher than head!

Weird or what!
 

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Discussion Starter · #23 ·
Now I have just checked my cct distance travel now from full tension of the chain after I release the key. In my findings it would seem the cct is pushing out 25cm to keep everything tight. I did this by locking the cct with the key at where it is set and then removing the full body away and checking measurements. I have also taken a fully extended measurement also to see where I am now to the maximum it will push put fully and that measurement was 33.5mm so I do have 8.5mm travel left in the cct.

Now I did this to see what others may be getting with there's in now taking up tension, by knowing a ball park figure will tell me if it is truly the chain that has stretched (elongated) or not.
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Discussion Starter · #24 ·
Hmmm I have just stumbled across a good read which I thought I would share, this would seem the exact problem I am having at the bottom. I am getting the same markings as he is when using the old chain to a new 1.

 

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Guess that article explains why I didn't have your issue. My motor had 32k miles on it when I put new cam chain and new tensioner.
 

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Discussion Starter · #26 ·
Yer that would make sense, I had the same problem when the bike was at 39,000 miles. Pretty much when I bought it .....2 weeks later I blew 2 exhaust valves and then the strip down and rebuild happened....Typical ay! Had the same problem then with the markings.....should of known better then but I put it back with the inlet lower on the case and higher on the exhaust and she fired right up.....only thing I can see now though that I never back then would be how the actual cam lobes were positioned. My guess now was that the intake was retarded at least 6 degrees and the exhaust cam was too.

Losing power lost in them lobe positions is lost hp yet she ran and never noticed a difference, wondering if it'll be night and day difference when there actually level like they shoukd be with the new chain and opening and closing like they should.

I use to hear people say they needed a steering damper and it shakes it head alot. Tbf I never had that problem EVER....and I do ring its neck everywhere.

I'll keep you all updated on my findings once it's here.
 

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I'll try to put you out of your misery.
1. the chain is meant to be bar tight. that level of wear is normal on the sprockets, but once bedded in, the wear hardly gets any worse.
2. I recently bought a new camchain because the old one had done more than 60,000 miles. Put the new one side by side with the old one to see how much sideways bend in the chain there was, you could not tell the difference. I have NEVER heard of one of these chains failing.
3. Regarding your timing issue, it won't be chain stretch because if you think about it, those sprockets are linked by the shortest run of chain, the chain would have to stretch enormously to account for your tiny discrepancy. In the end, all you are worried about is if the cam is one tooth out or not. You can easily check that by deliberately moving one of the cams by one tooth, and you'll see (with the tensioner in and working) that it's way out. The way you have it (and I assume you have the tensioner in and active) looks OK to me. If one cam is out by one tooth the engine runs like a dog, there is no doubt whatsoever.
4. be very wary of turning the engine over by hand without the tensioner operating. Without it's easy for the cams to skip a tooth. Then you've got the buggeration of loosening the camshaft holders again to get it timed.
 

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Discussion Starter · #28 ·
Cheers for your theory on this subject, I do appreciate it... I totally understand how it would look if I moved the cam an extra tooth,I know it would not look right as I have tried and tested it plenty of times before. The can just don't want to sit right when there not positioned right. The intake basically lays in place fine and so does the exhaust cam baring the fact they do kick out at the ends a tad on cylinder 1.not enough to be worried. Cam holders bed them down nice so I know there in there right locations because if they wasn't the cam holders usually struggle coming off evenly once the engines been turned a few times and once you slowly undo em they spring back. Now in the location there in now I don't get that at all and once fully loosend they just pull off fine. Now there is a fair amount of slack in between the cams after installing them enough to warrant the cams to slightly move when the engines being turned and the cam chain tensioner takes up that slack leaving them retarded.

I have tried and tried to get them level with the head but they just won't. The only thing that could be the case is the chain, its funny how that article I shared shows what happens when he used the old cam chain and showed his postion of the cams and the chain slack in between the cams was excessive to change the position of the cams and then showed the actual image of where the markings are positioned. That is exactly what I am getting right now.....he shows a new cam chain lines them markings back up true to the head.

I have nothing to lose by at least trying a new chain i will know, I have ordered already, I may get this tomorrow hopefully....I'm just hoping i do see a difference in my readings and I can put all this to bed and finally build the bike with a 100% confidence its bang on.
 

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Cheers for your theory on this subject, I do appreciate it... I totally understand how it would look if I moved the cam an extra tooth,I know it would not look right as I have tried and tested it plenty of times before. The can just don't want to sit right when there not positioned right. The intake basically lays in place fine and so does the exhaust cam baring the fact they do kick out at the ends a tad on cylinder 1.not enough to be worried. Cam holders bed them down nice so I know there in there right locations because if they wasn't the cam holders usually struggle coming off evenly once the engines been turned a few times and once you slowly undo em they spring back. Now in the location there in now I don't get that at all and once fully loosend they just pull off fine. Now there is a fair amount of slack in between the cams after installing them enough to warrant the cams to slightly move when the engines being turned and the cam chain tensioner takes up that slack leaving them retarded.

I have tried and tried to get them level with the head but they just won't. The only thing that could be the case is the chain, its funny how that article I shared shows what happens when he used the old cam chain and showed his postion of the cams and the chain slack in between the cams was excessive to change the position of the cams and then showed the actual image of where the markings are positioned. That is exactly what I am getting right now.....he shows a new cam chain lines them markings back up true to the head.

I have nothing to lose by at least trying a new chain i will know, I have ordered already, I may get this tomorrow hopefully....I'm just hoping i do see a difference in my readings and I can put all this to bed and finally build the bike with a 100% confidence its bang on.
I'll be very interested to see what difference a new chain makes. Are you renewing the sprockets too? In theory you should but that's only theory, eh? In practice though I renewed a cam chain without renewing any of the 3 sprockets , made no difference to the timing picture, and after running it for 2 years there was no change to the wear marks on the sprockets. These "silent" chains are awesome, don't know why all overhead cam engines don't have them.
 

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Discussion Starter · #30 ·
1 would think changing the sprockets when installing new chain would be ideal but I think for now I'll see how the chain is first and go from there, when you installed the new cam chain did you count 15 double links and match it to the manual picture.... I know it doesn't state this but if its how it was shown once fitted then u know for certain it's fitted right. I can see it being easy for some to want to move the left cam up 1 tooth to get better alignment with the markings.... I stuck with the picture and number of links they use.
 

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1 would think changing the sprockets when installing new chain would be ideal but I think for now I'll see how the chain is first and go from there, when you installed the new cam chain did you count 15 double links and match it to the manual picture.... I know it doesn't state this but if its how it was shown once fitted then u know for certain it's fitted right. I can see it being easy for some to want to move the left cam up 1 tooth to get better alignment with the markings.... I stuck with the picture and number of links they use.
The chain is supplied closed with a standard length . You just have to fit it.
 

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Discussion Starter · #33 ·
Yes I understand the chain is a whole chain with no possibility to split in with a link included. What I am saying is once you feed the chain down onto the drive gear you want to be positioning the chain over the exhaust cam and then the intake cam making sure there on the right chain links I.e the picture I have shown, pulling the chain up and tight onto the exhaust cam so it's level and then counting the links positioning it onto the intake cam (15 double links as shown) the cams will sit in nice this way, but for any1 chasing the markings I guess its easy to go up 1 on the intake and not notice this. The picture illustration can't lie as that's how it's been fitted though they never mention this in the manual about counting links.
 

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Yes I understand the chain is a whole chain with no possibility to split in with a link included. What I am saying is once you feed the chain down onto the drive gear you want to be positioning the chain over the exhaust cam and then the intake cam making sure there on the right chain links I.e the picture I have shown, pulling the chain up and tight onto the exhaust cam so it's level and then counting the links positioning it onto the intake cam (15 double links as shown) the cams will sit in nice this way, but for any1 chasing the markings I guess its easy to go up 1 on the intake and not notice this. The picture illustration can't lie as that's how it's been fitted though they never mention this in the manual about counting links.
OK, now I get what you are saying. Makes sense. I usually leave the sprockets on the cams then fiddle the camshafts under the chain with the camshaft holders not yet fitted (but the crankshaft in the right position). Through years of frustration I now know where they should be at this stage and after the holders are tightened down and the tensioner activated everything lines up. But I understand your caution.
 

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OK, now I get what you are saying. Makes sense. I usually leave the sprockets on the cams then fiddle the camshafts under the chain with the camshaft holders not yet fitted (but the crankshaft in the right position). Through years of frustration I now know where they should be at this stage and after the holders are tightened down and the tensioner activated everything lines up. But I understand your caution.
 

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Discussion Starter · #36 ·
Well....... my new chain has just arrived today so just put them side by side to see the difference.

If that isn't obvious enough then I don't know what is, let's hope everything will line up now as they should.

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Discussion Starter · #37 ·
Just installed the new chain following my theory on counting 15 double links like the picture. First thing I noticed was when installing the cams,they laid like spreading a womens legs on the opposite side, I assume with the new chain that's the reasoning. Got it all bolted down and torqued up, turned it 3 revolutions and boom...... bang on timing for the first time ever. All this for a bloody damn chain, I'm just glad I can start rebuilding again now.



Considering HONDA themselves say cam chain do not stretch and will last the length on the bike, do your own tests and make up your own minds because the proof is in the pudding, they really do and will alter your cam timing meaning lost power as the valves will be opening early.

Oh and I measured the cam chain tensioner afterwards, remember it was showing 25mm pushed out with the old chain,

Now it's measuring 19.5mm ( BIG DIFFERENCE)
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I got there in the end lol
Good work Dave, and useful data about the difference in tensioner extension. Now we can all measure our cam chain wear without tearing down the motor...maybe one of us can post the relationship between tensioner extension and number of turns of the tensioner screw needed to fully retract it . Any idea how many miles the old chain had done?
👏

Btw just figured out that with your worn chain which is only 1.2% longer than new, it means the exhaust cam would be 7.8° retarded. And the inlet cam 10° retarded. That's quite significant. I need to pay more attention to this!

Maybe a good reason to have adjustable cam chain sprockets....🤔
 
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