Unusual sounds eminating from a '98

Hey, guys!

Having put about 350 miles on my new bike since last Wednesday, I've come up with a couple of things that are disconcerting that I'd like to ask you all about.

The first is a clunk sound whenever I get on or off the gas suddenly.it seems as though there's play in the transmission, much more than I'm used to. Is this normal? I'll try to post a video when I get a chance.

The second is a chirping sound at idle. it sounds like a belt chirping or squeaking. Any ideas?

Thanksin advance for your help!

 

Check your chain tension

 

First thing I checked. This has the sound of transmission to it.....

 

98 year still has gear driven cams, and it does have a quite distinct whine, which is probably what you are hearing as chirping.

Now, for the clunk, trans gear dogs are a bit "looser" on VFR than on other crotch rockets, to ease shifting, so maybe this is a bit unusual to you? This is just a guess, since I did not hear it, so I could be way off

 

I'm a mechanic, so believe me when I say that I recognize the difference between gear whine and chirping. this sounds exactly like a belt chirping. Is there a belt on this engine anywhere?

I wondered if the slop in the transmission was a product of engineering or something was wrong. thanks for clarifying that for me.

 

There are no belts of any kind on this bike. I have the same year VFR, and I did a complete rebuild, so I do know

Cams are driven by gears, alternator rotor magnet is bolted directly on the crank, water pump is on the same chain driven shaft as the oil pump. This short chain is inside engine as well, lubed by oil from the engine.

Thinking out loud, there are no rubber moving parts at all.

Maybe a big seal on the output shaft, where the small sprocket is? Him, I think you mentioned this whistle is at idle, so this would not qualify then .... Starter seal would not be it, because of the one way clutch ..... Water pump seal? Any coolant leaking through the weep hole on the pump?

 

It might be the air box flapper valve. This flap will open and close often with a little "clunk" sound, but it could be making a squeaking sound from the spring inside the actuator or the plastic flap rubbing at the pivot points. I took the flapper off my '09, but left it on the '01 and I first thought something was wrong until I remembered the flap was still connected and working.

 

Thinking some more about the chirp:
- loose plastic /rubber parts, like fairings, mirrors, windshield, etc.
- secondary (PAIR valves per Honda) reed valves resonating in the head covers
- if sound changes with the clutch actuation could be related to clutch/plates
- if sound changes with engine rpm, could be a vacuum leak (rough idle?)
- flapper valve loose on the top of air box

 

I like the flapper valve Theory. I'll do some checking tomorrow and get back with you.

 

Flapper valve noise / clutch switch

[video=youtube;-r6E4ifofwI]http://www.youtube.com/watch?v=-r6E4ifofwI[/video]

 

Clunk could be excessive slop in cushdrive rubbers, possibly needing replacement.

 

Yeah....that wasn't the sound.

Whatever it was, it went away...so I've stopped worrying about it & am enjoying the hell out of twisting my right wrist~

The clunk is still there. What are cushdrive rubbers?

 

I know you said you checked the chain, but maybe check the front sprocket. I thought the clunk was just a sound my 99 made. When I was changeing the chain & sprockets, my front sprocket was wobbly on the shaft! Needless to say, my clunk went away with new sprockets.

 

Both sprockets were replaced with the chain @ 1000 miles ago. Wouldn't hurt to take a look, though.

 

Is this the clunking / popping I hear and feel when I first leave the stop sign?

I was thinking something in my VFR gearbox was loose or broken. However it shifts like a dream and I only get the clunking after I've been stopped. Then I thought it was a swingarm bearing problem but again, no obvious banging around when rolling.

Do I just disconnect that switch on the clutch as a way of determining if this is the source of my mystery pop?