Knocking On Heavens Door?

[Guest corpsy]

hey all

my 86 750 with 88000k had developed quite a loud tick/knock sound

to me it sounds like its coming from the left side of the rear bank about in the middle

it is silent when it is cold but after a ride its always there and seems to be getting alittle louder

performance seems ok.no difference when clutch is pulled and not really as noticeable at higher rpm

loudest at idle

to me it doesn't really sound like a loose valve but ive never herd one on a viffer

any ideas or could this be the end of the line?

[Guest]

Go down to your local auto parts store and get a stethoscope. I cut my teeth on V4's and it's an invaluable tool owing in no small part to the fact that with an inline four or CBX it's hard NOT to tell where a dink is located, as opposed to the V4's where sounds travel along strange routes. You'll hear things from within the crankcase that nature never intended. LOL.

My guess is rod knock but it all depends on the variably mettalic nature of the sound itself---valves are...higher pitched is the best way to describe it, rods/crankpins are more of a clunk. Chewed up cams; now there's an unearthly, and very cool, sound but of course it's the death knell...

Frequency of sound is important as well because you don't have a 180 degree crank. Tic--tic-tic says one thing, tic-tic-tic says another.

If you've got a friend with a *good* V4 to compare, all the better but no worry. As you move the probe around you'll find the sounding points and become better able to differentiate between valve, wristpin, crank, chain/sprocket, clutch, tranny etc.

Bottom line though: Knock=bad.

ON the other hand I've got a 100K VF1000 ('84) that makes a gawdawful racket. Seriously, wife says the dog starts wagging his tail when I'm a mile away, but it runs like a top.

Best of luck!

OSC

http://www.oldschoolcarbs.com

[Switchblade]

+1 Bad cam lobes She's done ......