A few small issues

[CieL]

Hi guys, I'm a bit of a beginner when it comes to engines, I just thought I'd let you know.

A few weeks ago I started feeling/hearing something vibrating in the engine while moving, in gear, starting at about 3000rpm and getting louder and vibrating faster if I accelerate further. For example if I'm in 3rd at 7000rpm it sounds and vibrates as if something is about to break in the engine. I had some free time today so I took the tank off in the hope that a nut would be loose, but no such luck, everything seemed in order. Could a shim vibrate that way if the valve clearance is too big?

I did notice though, while checking my air filter, that a few drops of oil went into the airbox. Is that something to worry about?



Also, do these sparks look alright to you? I have no starting issues, but I understand that you can tell a lot about how the engine is running from looking at the sparks.



And finally, I changed my oil two weeks ago and while unsuccessfully trying to remove the crankshaft nut (to change the gasket on the generator cover) I turned the crankshaft backwards for a bit. Soon after, while riding my bike, I started noticing that sometimes when I accelerate, even when in neutral, the rev needle bounces around a little bit. It didn't do that before I changed the oil and messed up with the crankshaft so my question is, what did I mess up in there? Compression issue?

Thanks.

[crackin]

When was the last time you synced the carbs? The vibration could be caused by out of sync carbs.
The oil on the filter has come out of the head breather line. Perhaps the filter in the top of the head is missing?
The plugs dont look too bad to me.

[CieL]

I haven't synced the carbs before, I'll probably do it after I get my hands on a manometer. Now that you mentioned it, the sound seems to be coming from the carburetor.

I actually snapped a couple pics of the breather, is the oil supposed to splatter like that on the cover?

 

[crackin]

It's fairly easy to build your own manometer.
I think the oil splatter is fine. At the end of the day this engine may be quite tired and in need of some love. Maybe the counter balance shaft bearings are toasted. It's hard to say with out riding the bike.

[Joolstacho]

Crackin, I reckon the occurrence of balance-shaft bearing wear causing noise would be SO rare. IMHO there are dozens of other things I'd want to look at before I looked at balance shaft probs.
OPs problems could be something as simple as chain wear, we don't have enough info.
Just a tip Ciel: If possible, change/do just ONE thing at a time, then, if you have problems afterwards you know where to pin it down.
If you change 3 things and something is wrong, well then you have to trawl though many more potential problems to track it down.
Eg, if you adjust your chain, then ride it and find there's an unusual/new noise, well, you'll know it's something in the driveline-chain and sprockets, -it won't be your valve clearances for example 'cos you haven't changed anything there. Some things can be inter-related, but the idea is to keep it simple as poss to help diagnosis.
Not meaning to 'talk down to you' mate, just passing on a good tip from old pros!
BTW Valve clearance issues will not be your problem, a rattling noise around the top end will tell you if this is happening, -I've never heard of valve clearances causing vibration.
Plugs look a bit sooty to me, but plug colour isn't much of an indication unless a proper plug chop is done.

[CieL]

Thanks for the pointers guys, when I get some free time I'm gonna start troubleshooting again.