Sporadic tapping noise from engine...

[rzgkane]

I get a sporadic tapping noise from the engine, moreso when hot. Seems I can induce the noise at cruise with a very light throttle and can make it go away with more gas. At idle, the sound hops around somewhat, sorta hit and miss. Here then gone.

Valve lash is correct and the sound is too inconsistent to be excessive valve clearance anyhow.

What are the usual suspects? Cam chain slop? I haven't taken the tensioner off and inspected yet. If I do remove the tensioner do I run the risk of any of the parts like the spring falling into the case?

Advance mechanism clatter? This seems to be a major repair and would require removal of the motor and disassembly of the lid. Someone told me some guys beat the weight rivets down a bit when they get loose.

Or is some noise in these motors just the nature of the beast? I like QUIET!!!!!

[jensen]

Hi,

These engines are quiet when in good condition, timed well, and synchronised.
Of course you can hear the engine running when idling, but hearing mechanical sound on top of the sound of the exhaust system while riding isn't normal.

If you can't figure out where the sound comes from, you could buy a stethoscope to locate it.

You did mention the most logic reasons, except big and and small end play on your rods.

No, the spring will not fall into the case when removing the can chain tensioner.

But before worrying about expenses, find the issue, and / or when you are not sure about the noise, find someone else with the same bike and compare.

Jensen

[rzgkane]

Thanks. Tensioner comes off this weekend for a look see. What are the options in the event it is a tensioner? Are there quality replacements out there? Seems like most are beat up and have taken on the look of the chain or, at best, they are 50 year old rubber waiting to look that way.

If it's the advance weights, well, that'll have to just clatter away for a while. No way I'm tearing into this motor to that degree yet!

Can imagine it's rods or end play because of how inconsistent it is. I'm hoping not, anyway.

Hi,

These engines are quiet when in good condition, timed well, and synchronised.
Of course you can hear the engine running when idling, but hearing mechanical sound on top of the sound of the exhaust system while riding isn't normal.

If you can't figure out where the sound comes from, you could buy a stethoscope to locate it.

You did mention the most logic reasons, except big and and small end play on your rods.

No, the spring will not fall into the case when removing the can chain tensioner.

But before worrying about expenses, find the issue, and / or when you are not sure about the noise, find someone else with the same bike and compare.

Jensen

[rzgkane]

Thanks. Tensioner comes off this weekend for a look see. What are the options in the event it is a tensioner? Are there quality replacements out there? Seems like most are beat up and have taken on the look of the chain or, at best, they are 50 year old rubber waiting to look that way.

If it's the advance weights, well, that'll have to just clatter away for a while. No way I'm tearing into this motor to that degree yet!

Can imagine it's rods or end play because of how inconsistent it is. I'm hoping not, anyway.

Well, it's not the cam chain tensioner. Took it off last night and it looks brand new. Someone musta just been through this motor right before I bought it. Next up is a stethescope.

[jensen]

Hi,

Maybe try to find someone in the neighbourhood with the same bike ?
Noises out of the engine (and in general) are very hard to explain in text,

Jensen

[rzgkane]

Hi,

Maybe try to find someone in the neighbourhood with the same bike ?
Noises out of the engine (and in general) are very hard to explain in text,

Jensen

No question it's hard to describe in words. And honestly, I haven't spent much time looking into it yet, as it's very sporadic and not very alarming. I'll enjoy the thing for a while before I get crazy.

[mike in idaho]

There are also the primary chain and the oil filter drive chain to consider as possible sources of noise. The primary chain has a spring-loaded roller against the bottom run, the top run will actually go a little bit slack, on the overrun(compression). The oil filter chain doesn't have any tensioning system for its chain so there is normally a little bit of slack in it too. These motors make a lot of little sounds when they run that you don't normally hear in modern bikes, that's part of their charm.