New bike, terrible noise

Yeah, could be someone check the valves and released the tensioner - 6 in the diagram above but never reset it... Been a long time since I did one so I can't remember if that's possible - you can remove the center bold and use a thin screw driver to reset it, I can't remember if that can be stuck.

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The engine looks like running fine beside the knock sound, +1 for the tensioner, probably a broken or stuck chain guide.
Anything like camshaft, valves problem would bring some smoke, Fi dash light or at least some engine hiccup.
 
Wouldn't hurt to pull the valve cover off the left side and see if there's anything visually amiss in there, run it briefly to hear/see the cams & lifters operating. To me a cam chain tensioner makes noise when the rpms change and the load on the cam chain increases and decreases causing the chain to "whip" and strike something nearby.
 
ST1300 cam chain tensioners adjust themselves - if that tool mentioned by Mellow in post #24 is removed and the screw is allowed to return by itself - it has a spiral spring inside which winds the helix out to gently press the tensioner against the cam chain. The helix which adjusts the tensioner can then only increase the tension to take up the slack. It can never release the tension.

However - you do have to make sure that the spring has returned it if you have used the tool to slacken the tensioner.

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If you don't have a stethoscope, a long handled screwdriver with handle pressed against ear, and blade probing different parts of the engine can helpt o identify the source of the sound.
 
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I’m in the camp of no rod knock- starts fine and runs well, a few seconds later is that knock- I would assume an actual knock would be immediately at startup and throughout the run cycle, no?
 
This is a fun guessing game. Given talk of a rusty tank my money is on an injector blockage so the bike is now running on only two or three cylinders. I know the V4 engines sound pretty rough and knocky when they aren't properly synchronised. Would be good to know the header temperatures. Another less fun option is if an injector was stuck open and filled a cylinder with fuel before the last start, which could give a hydrolock and a bent rod.
 
These engines will make a knock if one cylinder is not firing cleanly and carrying the load. Can be throttle body synch, bad plug or cap and/or fouled fuel injector. Good fuel with either Seafoam or fuel system cleaner with a PEA additive like Redline SI-1 will do wonders for fuel injectors and fuel system and combustion chamber and valve deposits.
 
No news yet. The mechanic said it would be a month before he could get to it. I will keep you posted as soon as I hear anything.
 
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