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[stinkwheel]

Does make me wonder about a valve seat too. Does it pop and bang when going downhill on a closed throttle? Do you ever go to start it and find there is no compression whatsoever until you've kicked it over a couple of times? Those were both symptoms mine had when the exhaust valve seat dropped.



Could also just be the valvegear bouncing if it's revving high with no load on the engine. Fine as long as the pushrods don't jump out of their seats.

[Lord-Toady]

I am not sure on the compression, I have at times felt like it has kicked over too easily with no compression but that was before I adjusted the exhaust tappet which was very tight. When adjusting the tappet it did kind of seem like it was a bit bent or out of true when turning it while it was too loose but I need to check it again. I have not really taken it over any hills yet as the hills near me are mainly on A roads and I have been keeping off them while getting used to the bike and learning to trust it.

I should clarify how it sounds on reflection, its more like a snapping which is why I said it reminds me of piston rings. Imagine putting a bit of sprung steel like a piston ring on a metal surface holding one side down and picking up the other and letting it snap down on the metal. Thats how it sounds snap snap snap snap snap intermittant for the first 3 seconds until the engine slows down then it is fine.

Maybe it is piston slap, I remember my old KLR 650 used to make a similar sound on startup and that needed a new piston as the piston was too small for the barrel but that also bellowed out thick smoke.

BTW someone on here recommended Snidal's book and I have been reading it seems a great book.

[Lord-Toady]

I dont mean a little quiet snapping either, think slapping the side of a metal tool chest with a steel metre ruler kind of loud.

[Lord-Toady]

Been looking at the engine diagram, isn't that clever when the bearing surface of the cam/rockers wears out you can just buy a bolt on rocker assembly with the bearing surface and the rocker combined for £30 instead of the whole cylinder head being scrap or needing expensive machining to resurface the journels, that's fantastic.

[AceHead08AVL]

No one has mentioned sprag clutch yet. Could it be your sprag clutch kicking back?

I'm not really totally clear if the noise happens while the engine is running OR when you are Trying to start the engine.

[Adrian]

Sprag clutch on a kick start bike? Er, no...

[Lord-Toady]

I went out for a ride today around the country lanes went on the A27 a bit and over some hills on the A29 just testing my new exhaust. It has been starting first kick but today it was struggling to start and embarrised me at the petrol station in fromt of Harley riders and in front of the bikers with their gleaming sports bikes at Whiteways Cafe.. I stopped down a country lane to take the below photo in the woods and the bike make the noise when trying to start and wouldnt hold idle. Turns out my intake manifold rubber had split a hole and the clatter may have been the carb spitting back amplified by the metal of the engine. A roll of insulating tape got me home and I have a new rubber in the garage already that i had not got around to fitting. Maybe i was mistaking spitting back at gigh unloaded revs for a mettalic sound.





delete meetup account

[Lord-Toady]

Some lovely country lanes around was at Madehurst. Another thing I keep hitting the choke on with my leg and that gives me trouble starting until I find its on so I might look at relocating it to the handle bars. The bike has been running great with the new exhaust up until splitting the manifold rubber, starting first kick and no back firing. I think my bike is jetted for it already but will check plug.

[Mark M]

Are you missing the head steady? Should attach to the lug above the inlet manifold rubber in picture 2.

REgards, Mark

[Lord-Toady]

My bike has never had that bar for some reason, wasn’t there when I bought it. Is it important? :/