JK1 Posted July 5, 2016 Author Posted July 5, 2016 That was not it... I´m starting to think that maybe the 1,5mm plate uder the cyliders is too low? The one it had last summer was 2,0mm. I checked the piston height but.... The other thing that has changed from last summer is the ignition... The bike starts better than before, but the idle is a little wavy. J Quote
JK1 Posted July 8, 2016 Author Posted July 8, 2016 Heres a new clip: I used a stetoscope to listen to the engine. The sound is coming from #1 cylinder head exhaust side but also from crank, same side... I guess I must open the f**ing thing... J Quote
wombat258 Posted July 8, 2016 Posted July 8, 2016 If it is a knock at the head and crank it is probably a failed big end bearing, and the piston is smacking the head. The oil should have a lot of metal in it in this case. Stop running it and tear it down. Although, I had a similar noise from my turbo and it turned out to be an unused a through-tapped hole on the exhaust housing that was leaking. Found it after I discovered it torched the paint on the chassis. Plugged the hole, and the noise was gone. Quote
bruteforce Posted July 13, 2016 Posted July 13, 2016 If your header is slightly warped it will leak at the gasket again. I'd check that again first to be sure. I'd then take the camcover off just to have a look if there are no loose tappets (if any), if OK then pop the sump off to search for debris. Quote
Reinhoud Posted July 14, 2016 Posted July 14, 2016 Faulty big end bearing knocks quite loud.. You don't need a stethoscope, a flat screwdriver will do, you probably can listen a little bit more detailed with that. I'm afraid it's going to cost you a new set off gaskets to find out what's wrong with it. Quote
JK1 Posted July 15, 2016 Author Posted July 15, 2016 Ok, problem solved. The plate under the cylinders was too thin (1,5mm). I changed it back to 2,0mm and now the engine sounds great! I also checked the whole engine and everything was ok. J 1 Quote
Gixer1460 Posted July 18, 2016 Posted July 18, 2016 Not my cup of tea but good engineering nonetheless..........I think that exhaust ain't gonna last too many roundabouts though! Quote
bruteforce Posted July 19, 2016 Posted July 19, 2016 JK, I get the impression you haven't checked deckheight then, as the pistons apparently were touching the ceiling with the 1,5mm spacer plate? Any idea what actual CR might be? I would make sure of that so it won't blow up because CR is still too high... Quote
Gixer1460 Posted July 19, 2016 Posted July 19, 2016 52 minutes ago, bruteforce said: JK, I get the impression you haven't checked deckheight then, as the pistons apparently were touching the ceiling with the 1,5mm spacer plate? Any idea what actual CR might be? I would make sure of that so it won't blow up because CR is still too high... That did occur to me - touching at 1.5mm and not at 2.0mm means only 0.5mm squish which is about half what it needs to be for a road bike! 1 Quote
bruteforce Posted July 19, 2016 Posted July 19, 2016 (edited) Fully correct remark Mr. Gixer1460! Edited July 19, 2016 by bruteforce Quote
wombat258 Posted July 19, 2016 Posted July 19, 2016 Pistons hitting the head usually flex and crack, and the bigend bearings get pounded. I would tear down and inspect fully, but that is just me I suppose. I hate cleaning up the damage when a rod says bye bye. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.