Anders Posted July 19, 2015 Posted July 19, 2015 I just bought a 2005 V11 LeMans from a private seller here in Sweden.I took it for a 10 minutes test ride,everything was great.Then on my way home after about 50Km I stopped for gas.This was the first time I could hear anything because of thundering headwind.I heard a banging noice ,like when you drive a nail into concrete.Not good,so I stopped and had it brought to a workshop.When he looked at it there was nothing wrong with the other valve clearances exept for the right hand inlet valve that was off by 5mm! So what I heard must have been the valve banging on the piston. Has this happened to anyone of you? The guy at the workshop only had time to have a quick look for now and it will be weeks before he has time to really dig in,so I'm asking you guys,what could have caused this? He said the push rod was fine by the way. Help and input appreciated.
JBBenson Posted July 19, 2015 Posted July 19, 2015 Are you saying that you removed the valve covers and the intake valve clearance was off by 5mm? Must have been 5mm to much clearance? I am surprised it would even run like this at all. In my experience the V11 is finicky....well, maybe that's just mine..... I guess the question is: when the valve cover was removed, was the lock nut loose or was it fixed in the "5mm off" position? I guess that you would have noticed it while riding if it was fixed, but just asking. Just readjust the valves and see if it runs. Honestly, when I do my valves I always worry that they will come loose at 80 miles per hour and I will destroy the engine and maybe me. But I tell myself that they would loosen up right away after starting, so if it starts and runs then I figure it's all good and away I go. Now I know that they can run for a while before letting go. Thanks a lot!
Scud Posted July 19, 2015 Posted July 19, 2015 Sorry to hear about your misfortune. Perhaps there is a mistake in writing? A 5mm valve clearance seems like enough to do serious damage (or prevent the bike from running); the gap is supposed to be about 0.10mm to 0.20 mm (depending on who you ask). 5mm would be 25 times bigger than the loosest recommendation that I've seen. Have you contacted the seller?
docc Posted July 19, 2015 Posted July 19, 2015 Agreed with the posters so far. A loose lock nut would be the likely culprit to allow to valve to loosen up. Also that 0,5 mm may be more likely? At a full 5 mm, the valve would not open at all and the motor would be running on one cylinder. Adjusting the valves and rechecking them fairly soon seems to be good method, and hopefully something you would not have to wait weeks for . . .
Anders Posted July 19, 2015 Author Posted July 19, 2015 Thanks for the input guys! I think the valve must have been loose reaching 5mm further into the cylinder.And yes,I'm sure he said 5mm.I only talked to the guy at the workshop on a cellphone when he explained it.The bike had a steady idle when I last had the engine running.Also when I was leaning a bit in the turn going into the gas station there was a rattle(of loose parts) and then the ding ding ding sound,all in the same pitch,sounding like it was the same parts making the sound all the time. I have contacted the seller,waiting for an answer. It seems like the damage isn't that big then ,as the idle was steady,and it was running OK except for the sound. I wonder though,how the hell could it even come loose? Maybe the spring broke and/or the lock nut? In any case ,it seems like the damage is all in the head,and no need to take the whole engine out.Right? I'll talk to some guys at a workshop nearer home that I usually go to,and see what they say. 1
docc Posted July 19, 2015 Posted July 19, 2015 If the valve adjustment "loosened" the valve would not reach further into the cylinder, but simply would not open. 5 mm into the cylinder, (I would think) would put the valve into the piston (very bad). It really sounds like the adjusting lock nut came loose (noisy, but no real damage). Just a valve adjustment - no engine tear down.
gstallons Posted July 19, 2015 Posted July 19, 2015 You can remove both valve covers and see how much of the adjusting screw is exposed above the rocker arm on the other side . If they are close or the same after adjusting , you are o.k.
Anders Posted July 20, 2015 Author Posted July 20, 2015 If the valve adjustment "loosened" the valve would not reach further into the cylinder, but simply would not open. 5 mm into the cylinder, (I would think) would put the valve into the piston (very bad). It really sounds like the adjusting lock nut came loose (noisy, but no real damage). Just a valve adjustment - no engine tear down. You can remove both valve covers and see how much of the adjusting screw is exposed above the rocker arm on the other side . If they are close or the same after adjusting , you are o.k. Big thanks once again for your input guys!! I will look into it.I really hope it's just a valve adjustment.
Admin Jaap Posted July 20, 2015 Posted July 20, 2015 Hoping for the above but it could also be a bad pushrod. I've seen a 2005 Cafe Sport once with similar clearances
Anders Posted July 20, 2015 Author Posted July 20, 2015 Hoping for the above but it could also be a bad pushrod. I've seen a 2005 Cafe Sport once with similar clearances Oh,the guy looking at it at the workshop told me the pushrod was OK too,I forgot to mention that.Do you know what could have caused those bad clearances on that bike you saw?
Lucky Phil Posted July 21, 2015 Posted July 21, 2015 Assuming 5mm is a misinterpretation it may be lifter/ lobe failure. Ciao
Admin Jaap Posted July 21, 2015 Posted July 21, 2015 Hoping for the above but it could also be a bad pushrod. I've seen a 2005 Cafe Sport once with similar clearancesOh,the guy looking at it at the workshop told me the pushrod was OK too,I forgot to mention that.Do you know what could have caused those bad clearances on that bike you saw?From what I remember it was a case of an extremely worn pushrod. So it must have been a production problem. The bike was almost new
gstallons Posted July 21, 2015 Posted July 21, 2015 If you suspect it is a cam lobe failure , get a dial indicator and set it up to check the lift of the cam lobe . Check both sides and compare what you find . They should be within 0.005" .
Anders Posted July 22, 2015 Author Posted July 22, 2015 Assuming 5mm is a misinterpretation it may be lifter/ lobe failure. Ciao Aha,thanks good to know. Hoping for the above but it could also be a bad pushrod. I've seen a 2005 Cafe Sport once with similar clearancesOh,the guy looking at it at the workshop told me the pushrod was OK too,I forgot to mention that.Do you know what could have caused those bad clearances on that bike you saw?From what I remember it was a case of an extremely worn pushrod. So it must have been a production problem. The bike was almost new OK,could perhaps be cam lobe faliure then. If you suspect it is a cam lobe failure , get a dial indicator and set it up to check the lift of the cam lobe . Check both sides and compare what you find . They should be within 0.005" . Great! I'll talk to the mechanic at the workshop about it. I'm really apretiate your help guys!
motoguzznix Posted July 24, 2015 Posted July 24, 2015 Anders I won't discourage you, but I suppose it might be a bent valve that remains open 5 mm. That can either be caused by charcoal in the valve guide or by a too tight valve guide play. In that case the valve sticks in the guide and the piston on his way up the bore hits the valve. If you are lucky it is a shrinked pushrod as mentioned above. remove the rocker and pull the pushrod. In case of a shrinking you can observe an aluminium rollover at the connection to the steel end caps. You can remove the other pusrod too to compare the length. In that case replacing the pushrod is a cheap repair.
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