[92xjunker]

Those are crush washers. Oil, brake lines or cylinder head.... my guess cylinder head. Under every stud nut is a crush washer.

[Ding dong]

You know where my rectifier is on my 99?

[92xjunker]

In the alternator.

[Gabriel Dark]

My engine is like a kinder surprise.
This fell out when I opened starter clutch cover. As you can probably guess, I will now ask can anyone identify this piece? I estimate that it is part of something that is about 7 cm in diameter.

[Gabriel Dark]

If I am right its a bottom of the cylinder sleeve.

[92xjunker]

I don't think so. That would be in the oil pan. There is only three part in the starter area. Starter, intermediate gear and the starter clutch/gear. I'd pull the clutch gear and inspect it. Backfire or any reason the engine would be forced backward could break that clutch, although that's what it's there to prevent.

[Gabriel Dark]

I honestly hope you are right. After looking at some pictures of cylinders, I am 90% sure its piece of cylinder but I will listen to your advice and check that clutch first.

[Gabriel Dark]

Broken cylinder. Already taken care of.


I have another problem...
when I was putting back engine sprocket I removed rear wheel so I could put a chain arround engine shaft. When I mounted rear wheel back I set up chain slack but I have noticed that slack is changing as I am spinning wheel. The wheel itself is spinning like it should half of revolution and other half is spinning significatly harder. When I measured position of rear sprocket compared to rear fork, it really is moving 3 milimeters forward and backward.


I am sure I have returned everything like it was and I did everything by the book... Supported wheel and all that. Also I tightened it to 80Nm because when i tried 100 like it is stated in manual, wheel was barely spinning.


Any ideas?

[Gabriel Dark]

Ok, I solved problem refering to hard spinning. Wheel was overtightened. I torqued it to 60Nm and it is alright now.


the problem with sprocket moving forward/backward still remains. I will measure it because I think its manufactured like that. I cant think of anything else.

[92xjunker]

That would be a bearing or spacer issue. You need to figure that out or risk alignment and chain issues that won't be pretty.

[Gabriel Dark]

And finally, last problem has appeared. I cant start the bike. 😊


Fuel valve is ok
Carburatores should be fine (cleaned 3 months ago)
Spark plugs get wet from fuel
Spark plugs throw sparks
Compression is ok
Engine timing is correct


Last time when tried to start the bike i reved it (with a starter motor) for like 20 seconds and it produced a loud bang from exhaust. Really loud. Ocasionally it starts for a second but that is rare, and one time it even reved to 3000 rpm and just died.


Is it possible that sparks get thrown at wrong time. I had almost identical symptoms on M5 few years ago and it was malfunctioned cam position sensor. I dont know is something similar possible on Katana.

[92xjunker]

Backfire or afterfire.....if the coil input power were on the wrong coil it could backfire ( threw the carbs). Plug wire location could also cause it. After fire would be a lean carb issue, loading the exhaust with fuel vapor then igniting.

[Gabriel Dark]

I am quite sure that coils are connected like they should be. I didnt remove them from harness and left coil goes on first and fourth cylinder and right coil powers second and third cylinder.

I am not 100% sure but I think it was afterfire on the exhaust.

I can clean carbs again but if that dont help I am completely out of ideas.

[shpielers]

Are you getting 11v to the coils when the starter is turning over? Cause less can give a spark, but not strong enough to turn the engine/ignite.

[Gabriel Dark]

Is it normal for spark plug cables to have arround 5 kiloohm resistance?
That is actually resistance of spark plug connector itself. Anyway, is that normal resistance?


I am also measuring over 20 megaohm (probably infinite) resistance on one of the ignition coils (spark plug side). Is it even possible to throw a spark with such a resistance (because I have spark)?

The primary side of both ignitio coils is 2.8 ohms and signal generator is 165 ohms so that should be ok.