I have a knock that I hear in my engine in idle in nuetral, I also hear it in Idle at lights. but this is at a point where the bike idles so low it is about to stall. maybe it is pre-detonation, a bad spark or I don't know.

It seems to be coming from the crank area on the left side or the middle.
at anything above 1500-1750 RPM it isn't there, nor do I hear anything under load. I know what a knocking rod sounds like in a car but that is constant throught the RPM range. this is only at low low RPMs it isn't very pronounced either kind of a knock here and there.

the bike has a APE manual chain tensioner and I am going to try to adjust that tomorrow. I don't want to spend alot of money to have a dealer work on it as the bike was only 800 bucks. I have seen used engines for 399 on Craigslist and Ebay, maybe it is nothing I don't know.

Any help would be greatly appeciated.
Thanks
Patrick



UPDATE
Went out in the boiling 101F sun today to try to figure out the issue.
Upon much closer inspection it does NOT seem to be the crank or the rods.
this noise happens when the thing is in nuetral without the the clutch engaged.

Engage the clutch a viola the noise is gone.
So I am thinking there maybe something loose in the clutch area.
problem is I cant have my head next to the motor while engaging the clutch.
Will have my wife hold it when it cols down and I have a bit of shade.

This noise is kind of like you hear the motor rotating and oxcasionally a couple of light knocks like you would rap on the engine case with a rachet,. there is no specific timing of the knock just run run run knock run run run run run run run knock and so on. I did adjust the Manual CCT and that isn't the issue the knocks seem to come from the lower end of the engine. and only when clutch is disengaged. I am hoping this is standard engine noise but I don't know better.

 

I had the same problem with my first engine. It had a carb problem though and one cylinder wasnt firing. It was basically dragging piston #1 and making that same type of sound. Check your header temps and see if they are all the same. If not you could have a similar problem. If they are ok, back to the drawing board. I ended up swapping out my engine for one off of Ebay, and realized I was having the same problem as before. had to figure out my carb problem before proceeding. At least you can find some decent engine replacements out there at reasonable prices, if it comes to that.

 

these bikes have noisy clutches. it is completely normal. most f2 owners will attest that their clutch makes noise. i wouldnt be very concerned about it unless it sounds like its going to cause the cover to implode

 

Well I took the clutch apart.I also found the gas tank had none or junk for buhings so replaced. the clutch plates, all looked good re tightend it and adjusted the CCT and A LOT of noise went away and was riding smooth.
SAD news!!!!!!!!! hours after the work the bike was STOLEN!
I recovered it not far from my apt parked. guess the guy hurt himself dropping it and bailed. but screwed my ignition all up and really scrached the stator cover but no cracks. I got a new coke machine ignition and alarm system ordered to alleviate the freaking screwdriver through the keyhole issue and spent 100 bucks on locks and chains. So now to get this bike you have 5 locks, chains and cables to go through bought 4 different kinds to make sure one toolkit won't do the job.
Now the idle and throttle seem to stick for a while then loosen up and throttle down. my guess is pinched throttle cable.

and the somewhat came back
vibration sometimes is there sometimes is not.
not nearly as bad as it was before, even after the theft.

Bought some oil for cables and linkages if that doesn't fix it going to break down and take it to the shop.

I have !@##@$$# for luck.