NEED HELP PLEASE
-
tugboatlife
- Rookie
- Posts: 4
- Joined: Wed Mar 04, 2009 4:24 am
- Sex: Male
- Location: Sunbury,NC
NEED HELP PLEASE
I have a 1980 honda cb900c the left side of the motor has a tapping or slapping noise comeing from it it only does this when you give it gas it has not lost power but i have straight pipes and you can hear the noise over them when you give it gas if anyone knows what this may be please let me know i'm going on a long ride to a rally in may and want to figure this out
i had a cb750c that year and my bet would be on tappets/valves.
if you have a stuck valve it'll make that noise as the tappet hits it, or if they're just not adjusted properly it'll make a tapping/slapping noise whenever they're working. as far as it only making the noise when it's being revved (if you're not positive on that part let us know) it could be because while it's idling there's enough oil up there to muffle it but as it's gassed there's less oil and the noise is longer.
i realize that you said it hasn't lost power, and if it had a stuck valve that would certainly be the case, but it's hard sometimes to tell if 1 cylinder isn't firing right on that bike (disconnect one spark plug and you almost can't tell.
other than those, try to decide whether the noise seems to be coming from the top or bottom end of the engine. everything i said will be felt and heard mainly at the top end.
check your oil level (its a 30 year old oil pump help it out)
put your hand over the exhaust, does it feel the same on both sides?
if you have a stuck valve it'll make that noise as the tappet hits it, or if they're just not adjusted properly it'll make a tapping/slapping noise whenever they're working. as far as it only making the noise when it's being revved (if you're not positive on that part let us know) it could be because while it's idling there's enough oil up there to muffle it but as it's gassed there's less oil and the noise is longer.
i realize that you said it hasn't lost power, and if it had a stuck valve that would certainly be the case, but it's hard sometimes to tell if 1 cylinder isn't firing right on that bike (disconnect one spark plug and you almost can't tell.
other than those, try to decide whether the noise seems to be coming from the top or bottom end of the engine. everything i said will be felt and heard mainly at the top end.
check your oil level (its a 30 year old oil pump help it out)
put your hand over the exhaust, does it feel the same on both sides?
**1981 Honda cb750c** (for sale)
**1989 Kawasaki 454 LTD**
**1989 Kawasaki 454 LTD**