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Discussion Starter #1
Hi everyone, wondering if anyone can help.

Recently bought a 2004 Bird with 35000 miles on the clock. It has a knocking sound at idle when warmed up, not when cold. Doesn't go away with the clutch in or out or in neutral or in gear. It goes when under load, so holding the brake and letting the clutch out and throttle on. It's gone back to the dealer, he's changed the clutch basket and done an oil pressure test and can't figure out what the issue is. Next would be going into the engine. I've seen a few threads where lads have said they have the same issue, some say it's springs at the back of the clutch basket that have gotten compressed. Anyone have anything similar or any ideas??? It's not the cct.

TIA
 

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I remember hearing a similar sound only when hot, but not a knock sound, more like tock tock. I ignored it, for years and years, nothing bad ever happened. I surmised it may be coming from the counter balance shalt(s) but never actually looked into it.
 

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Could you try and get a recording of it. It may help us to figure it out.
 

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Discussion Starter #5 (Edited)
I had tried but the knocking sound is hard to record over the engine so doesn't come out when played back.

Similar to the knocking in the background here
 

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It has a knocking sound at idle when warmed up, not when cold.
What is the idle set at? You can get all sorts of abnging and knocking noises if it is too low. Set at 1200.
 

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It's about 1100/1200, once it warms up it idles fine. Another thread on here had leaking coils as the issue and stopped a similar sound.
 

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Agree with Duck. If yours sounds like that then it's most likely a low idle induced condition. Bump it to 1300 at least. I run mine at 1500. Gives another benefit this high, comes in closer to the R/R's charging point (about 22 to 2500). It can make a bit more clunk when dropping it into gear from a stop but its not going to hurt anything.
 

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Mines the same at low revs, very noisy which may have something to do with the balance shafts having been removed. As bees says upping tickover to 1500 stops it.
 

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I'm original owner of a 2000 and mine has always done the same. I can't say I remember any knocking when it was original stock (but that was MANY years & beers ago) but as I modified the engine I certainly noticed it more. When it's cold it fast idles fine. Then once it's warm and the idle drops to normal (1100 or so) but not full running temp yet it knocks and sounds like it's missing. Once it gets to full running temp after a few miles it then idles fine. I just hold the throttle open a bit to keep it from knocking until it gets up to full running temp.
 

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Hi Monsham,

I had a listen to your video and it sounds like the throttle bodies need vacuum balancing. While you are at it maybe it's time for some new plugs, and an airfilter if necessary. Done well, the Bird will run like a jet turbine.

The idle needs to be near 1200...... I have about 1250 on mine...... it helps prevent any low rpm stall if you are a bit slow with the heavy-ish clutch lever (if the motor bogs down in a tight turn etc), and certainly helps keep the motor quiet at idle.

Mine is running a bit sad as I haven't been able to ride it for 18 months and starting it in the garage monthly isn't as good as riding it for the day. I need new plugs anyway, so if I don't keep the rpm up while warming the BB up on my monthly garage rides, it will clank and clatter like yours.........(mine is an 05 with 81k miles/130k kms on the odo)

35,000miles (approx 56k kms) is very low mileage for one of these things........ just wait till you have 200,000miles on it (y)
 
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