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Get the engine from the other chap on here or buy one for less than a thousand bucks still un-molested and put it in there and save a billion man hours so you can RIDE...........
These bikes seem to go forever without major engine issues I would be wary to trust one that some knucklehead has dug into myself.
 

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Discussion Starter #42
The knock is just on the top of the revs, on the road under load it was really loud. Got a mate to rev it whilst I had a listen around, and pretty much 100% bottom end. Weird for such a low mileage engine (actually i haven't checked engine numbers!) but even then they are renowned for being a strong bullet proof engine . I mean you can turbo /supercharge on a standard bottom end! Time to take a look inside..
And yes im thinking same thing Find a decent low miles engine and swap em over!
 

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The knock is just on the top of the revs, on the road under load it was really loud. Got a mate to rev it whilst I had a listen around, and pretty much 100% bottom end. Weird for such a low mileage engine (actually i haven't checked engine numbers!) but even then they are renowned for being a strong bullet proof engine . I mean you can turbo /supercharge on a standard bottom end! Time to take a look inside..
And yes im thinking same thing Find a decent low miles engine and swap em over!
I would start looking behind the lower right crankcase cover - have a very close look at the camchain sliders/guides for wear.
Then move to the top of the motor - cam cover - also look at the cam sprockets & guides.
Then - if the above looks ok - drop the sump pan and inspect from underneath.

You may find/see the issue before you go ripping the motor out of the frame.
 

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Discussion Starter #44
Good advice thanks Dean. I'll do that first. However, that knock does seem to be coming from the bottom end. I'm not sure if you could hear it from the recording.. Only under load.
 

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Good advice thanks Dean. I'll do that first. However, that knock does seem to be coming from the bottom end. I'm not sure if you could hear it from the recording.. Only under load.
Had an old 900 motor that had a similar sound and it turned out the previous owner had fitted a manual cam chain tensioner and didn't have a clue how to set it up.
The engine had almost worn through the cam chain guides and sounded like it had a bottom end knock.

Set of new cam chain guides - a new cct and she ran sweetly again.
 

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Discussion Starter #47
Had an old 900 motor that had a similar sound and it turned out the previous owner had fitted a manual cam chain tensioner and didn't have a clue how to set it up.
The engine had almost worn through the cam chain guides and sounded like it had a bottom end knock.

Set of new cam chain guides - a new cct and she ran sweetly again.
That sounds promising! To be honest i wouldn't know how to tell the difference between a manual CCT and an auto one.. A mate who has a BB said to put a screwdriver in the hole, wind it up till it stops, then pull the driver out and let it go.. I did that.. Made no difference. I put a small screwdriver in and started the bike and as the revs went up the screwdriver went around and back again, so presume it's working?
Definitely worth checking the cam chain guides by the sound of it, and who knows why the PO changed the CCT and why he had the top off anyways.. Think you're right to check.
And Duck, yes sir, checked with the listening stick and knock appeared to be coming from the bottom..
 

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To be honest i wouldn't know how to tell the difference between a manual CCT and an auto one
Sounds like you have an auto one since you have been able to insert a screwdriver. FYI a manual one is adjusted by a 'bolt' so you would have been confronted by a bolt head. That said who knows what was fitted previously …..
I don't find anything strange in the CCT having been changed, to me these are a 'service part', they fail on a 'regular' basis but the top end being removed sounds more suspicious, 110K miles on my Daily Bird and the top end has never been removed.

Again FYI you can remove the cam chain guides without a major strip down. The rear is easy, cam cover off, remove the tensioner and pivot bolt and the guide can be lifted out from the top. The front is move difficult, but can be extracted through the lower cover. Suggest you start with the rear guide and check it. When I changed mine the wear was negligible so if you see any wear you know something has ben going on.
FWIW I would change the CCT now since that would rule that out. FYI when my supercharged Bird was first run up to full power there was a loud knocking (sounded terminal) when we hit +9K. Turned out that the new auto CCT had failed to maintain its pressure so we had to go 'manual', does this tie up with your high rev knocking?
 

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Discussion Starter #49
FYI when my supercharged Bird was first run up to full power there was a loud knocking (sounded terminal) when we hit +9K. Turned out that the new auto CCT had failed to maintain its pressure so we had to go 'manual', does this tie up with your high rev knocking?
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Thats VERY interesting Duck.. The CCT is new, but it may be a crap one..? Do you guys fit genuine or is there a suitable alternative ?
 

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Discussion Starter #50
Also there has been an occasional 'pulse knocking' which according to a mate with a BB is the clutch basket and is normal? (feel it through the whole bike)
Its the loud squealing that i thought was definitely not right. Seemed to be coming from the rear of the engine block and never lasted long enough to properly hunt down
 

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Your mate is probably correct wrt the 'pulse knocking' upping the idle to 1200 gets rid of it (if it is the clutch basket) horrible sound when it sets in.
Could the squealing be one (or both) balancer shafts? When they are out they whine but the pitch changes as the engine warms and tolerances alter.
 

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Again FYI you can remove the cam chain guides without a major strip down. The rear is easy, cam cover off, remove the tensioner and pivot bolt and the guide can be lifted out from the top. The front is move difficult, but can be extracted through the lower cover. Suggest you start with the rear guide and check it. When I changed mine the wear was negligible so if you see any wear you know something has ben going on.
FWIW I would change the CCT now since that would rule that out. FYI when my supercharged Bird was first run up to full power there was a loud knocking (sounded terminal) when we hit +9K. Turned out that the new auto CCT had failed to maintain its pressure so we had to go 'manual', does this tie up with your high rev knocking?
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The front is held by a small bolt at the bottom accessed by the ignition cover.
 

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Discussion Starter #54
Great, cheers Ade

Your mate is probably correct wrt the 'pulse knocking' upping the idle to 1200 gets rid of it (if it is the clutch basket) horrible sound when it sets in.
Could the squealing be one (or both) balancer shafts? When they are out they whine but the pitch changes as the engine warms and tolerances alter.
I checked the balance shafts after i first heard the squeal.
I first heard it whilst it was idling, it was seriously loud (not the noise that the balance shafts make, from what i could tell by adjusting through the range) and it disappeared above 2.5k rpm then as the revs dropped continued to squeal, then changed pitch (lower) then stopped.
Thought I heard it again whilst riding, shortly before the knocking started..
When I get 5 I'll check the cam chain guides, see what i find and report back :)
Thanks guys for all your input, appreciated
 

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Discussion Starter #56
Been waiting on another upgraded CCT from Jaws (ordered Monday) still not arrived.. Wanted to swap that in whilst I'm working on the bike.. Been working on my old 1400 chopper this week
HOPEFULLY the CCT will arrive, the weather will be dry, and i can start pulling the plastic off the Bird and have a good poke around :)
 

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Discussion Starter #59
They said if i hadn't of contacted them i probably would never had received it ��
 

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Discussion Starter #60
Bit of a late update, been lots going on (including 'partner' deciding to fck off with the kids!)
only just got the weather and time to pull the cover off the bird and have a look..
The CCT was fine as are the guides..
Engine was seriously squealing once it started to get warm, i readjusted the balance shafts and it wasn't that..
So decided to take it up slowly through the revs and listen.. At 3k + the loud squealing stopped
At 7k the revs started to fluctuate, the knocking was present but not loud, at 8k the engine made a bit of a rattle and then immediately shut down.. Felt very tight to start again and when it did it sounded like a bag of spanners
Engine is officially f*kd
I knew i should have got that 34k engine i spotted for £350 a couple of months ago!
 
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