Gen 2 engine not running/ 2nd post for help diagnosing issues

[Ravenna]

Ok this is my second attempt at rotating the internals as a whole. I have taken the inspection cover off and rotated the shaft a full 370 degrees and then it stops like its binding internally. I also dropped it into 5th gear and tried rotating the rear wheel at that point and I can't get past it. At the same time while it was in 5th I rotated the cam counter-clockwise and it turned the wheel back and forth. The engine is not hydro locked, nor does it have any visible damage or cracked block! Fresh oil was put in 5 months ago but, it hasn't ran in two years and has been kept nicely. I also removed fuel tank and checked the spark plugs but have not yet checked the injectors... Does anyone with engine experience have any ideas? The only thing I can possibly think of is a valve not seating properly and out of timing not letting it rotate properly? Idk I dont really want to remove the head much less the engine but, I at a loss other than sticking a scope down into it.

[jwcfbd]

Ok this is my second attempt at rotating the internals as a whole. I have taken the inspection cover off and rotated the shaft a full 370 degrees and then it stops like its binding internally. I also dropped it into 5th gear and tried rotating the rear wheel at that point and I can't get past it. At the same time while it was in 5th I rotated the cam counter-clockwise and it turned the wheel back and forth. The engine is not hydro locked, nor does it have any visible damage or cracked block! Fresh oil was put in 5 months ago but, it hasn't ran in two years and has been kept nicely. I also removed fuel tank and checked the spark plugs but have not yet checked the injectors... Does anyone with engine experience have any ideas? The only thing I can possibly think of is a valve not seating properly and out of timing not letting it rotate properly? Idk I dont really want to remove the head much less the engine but, I at a loss other than sticking a scope down into it.

The first thing I would look at is the valves and timing. Make sure your pistons are not hitting the valves. There are plenty of cheap scopes that'll let you see in the cylinder. Do you have all spark plugs removed? If someone put the wrong ones in maybe they could be hitting as well. Have you seen it run or did you just buy it this way?

[Ravenna]

The first thing I would look at is the valves and timing. Make sure your pistons are not hitting the valves. There are plenty of cheap scopes that'll let you see in the cylinder. Do you have all spark plugs removed? If someone put the wrong ones in maybe they could be hitting as well. Have you seen it run or did you just buy it this way?

Long story but, I bought it new several years ago and droppped a lot of $$$ into it! No actual engine work done to it... Ran purrfekt until someone hit me one night out of nowhere and woke up in the hospital! Now I'm trying to replace everything that was damaged but engine will not rotate consistantly and is bogging the starter when presssed, which is good. I am the only person to ever touch the bike mechanicaly! Had new oil,new plugs, and everything was top tier before going down! I have absolutey no recall of what hit me or how! Minor cover damage on starter and clutch but I have replaced those. Absolutely no signs of anything else going on otherwise! I can't for the life of me figure out why this is going on...I could see if the block was broken or cracked but it's not' But yes, I removed the tank completely and the plugs. I've got a friend with a scope so, I'm giong to borrow it and take a look when I get a chance but wanted to make sure I wasn't possibly missing something else?

[Bumblebee]

Long story but, I bought it new several years ago and droppped a lot of $$$ into it! No actual engine work done to it... Ran purrfekt until someone hit me one night out of nowhere and woke up in the hospital! Now I'm trying to replace everything that was damaged but engine will not rotate consistantly and is bogging the starter when presssed, which is good. I am the only person to ever touch the bike mechanicaly! Had new oil,new plugs, and everything was top tier before going down! I have absolutey no recall of what hit me or how! Minor cover damage on starter and clutch but I have replaced those. Absolutely no signs of anything else going on otherwise! I can't for the life of me figure out why this is going on...I could see if the block was broken or cracked but it's not' But yes, I removed the tank completely and the plugs. I've got a friend with a scope so, I'm giong to borrow it and take a look when I get a chance but wanted to make sure I wasn't possibly missing something else?

I wonder if it revved out while laying on it's side and starved the bearings for oil partially seizing them? I know the tip over sensor is supposed to prevent this, but weirder things have happened before.....

You very well could have lower end damage from this.....

[jwcfbd]

I wonder if it revved out while laying on it's side and starved the bearings for oil partially seizing them? I know the tip over sensor is supposed to prevent this, but weirder things have happened before.....

You very well could have lower end damage from this.....

Yeah anything is possible. Depending on how hard of a hit maybe there is unseen internal damage. Maybe a broken bearing or gear. Start with checking the timing marks to make sure your timing chain didn't jump a tooth of two. If that lines up then look at things like the front sprocket to see if the shaft looks bent at all. Does it spin freely when it's in neutral? If all external things look good then it sounds like it time to pull the engine and split the case.

[Bumblebee]

Yeah anything is possible. Depending on how hard of a hit maybe there is unseen internal damage. Maybe a broken bearing or gear. Start with checking the timing marks to make sure your timing chain didn't jump a tooth of two. If that lines up then look at things like the front sprocket to see if the shaft looks bent at all. Does it spin freely when it's in neutral? If all external things look good then it sounds like it time to pull the engine and split the case.

I remember way back in the day when there were RZ cup races.....we were watching when a bike came off the track flipped a few times and the throttle stuck open, it screamed for a bit and then "pop" it was gone......

Saw this happen to a snowmobile too.....a '67 16 horse Olympic that took off across the yard at full throttle into a bunch of saplings...by the time my brother got over to it, "pop." When he started it in the morning he had the habit of holding the throttle wide open while giving it choke......this one morning it didn't go so well.....

[Oz22]

Sometimes it pays to just drop a new motor in and save all the drama. personally I'd sell the bike, or scrap it. I wouldn't be refurbishing it after an accident like that. It's not like they are expensive now.

[Bede1026]

Maybe you should boar scope each cylinder see if it dropped a valve.

[michael parris heuberger]

Maybe you should boar scope each cylinder see if it dropped a valve.

Hi. Make sure all the pistons are moving too. Ad a long time back a friend said her car lost some power. I pulled the head 4 cylinder car and 3 pistons were at TDC and 1 was at BDC. Check every thing.

[Kiwi Rider]

Remove the valve cover….

Set the crank at TDC compression stroke…

Check for correct cam timing at the cam sprockets…

If timing is correct, check for bent valve/valves by looking for excessive clearance between cam lobe and bucket… if a valve is bent and off it’s seat, it will not be flush and in-line with all other valves.
If you remove the cam journals and the cams, you’ll see which valve buckets are sitting lower indicating bent valves
You could also do a leakdown test on every cylinder at TDC compression stroke.
Any bent valves in any cylinder will be identified As leaking compression immediately.
Identifying bent valves is pretty easy, and this may very well be the cause of the full rotation of the crankshaft being prevented.
A valve may have broken and dropped into the top of the piston too.
You just have to inspect it thoroughly.

[Kiwi Rider]

Hi. Make sure all the pistons are moving too. Ad a long time back a friend said her car lost some power. I pulled the head 4 cylinder car and 3 pistons were at TDC and 1 was at BDC. Check every thing.

Sounds like one of the pistons at TDC had disconnected itself from the crankshaft and or con rod lol!
I’ve seen this happen too, funny to look at lmao!

[Kiwi Rider]

I have taken the inspection cover off and rotated the shaft a full 370 degrees and then it stops like its binding internally. I also dropped it into 5th gear and tried rotating the rear wheel at that point and I can't get past it. At the same time while it was in 5th I rotated the cam counter-clockwise and it turned the wheel back and forth. The engine is not hydro locked, nor does it have any visible damage or cracked block!

whenever you turn over the engine with a socket on the flywheel bolt, (left side of the engine) ALWAYS turn crankshaft anticlockwise in the normal rotation of the engine.
If you attempt to turn it against the normal rotation, in a clockwise direction, you will lock up the starter clutch and in turn rotate the starter motor which causes a huge amount of drag and resistance on the crankshaft.
Just sayin…

[Kiwi Rider]

I have taken the inspection cover off and rotated the shaft a full 370 degrees and then it stops like its binding internally. I also dropped it into 5th gear and tried rotating the rear wheel at that point and I can't get past it. At the same time while it was in 5th I rotated the cam counter-clockwise and it turned the wheel back and forth. The engine is not hydro locked, nor does it have any visible damage or cracked block!

whenever you turn over the engine with a socket on the flywheel bolt, (left side of the engine) ALWAYS turn crankshaft anticlockwise in the normal rotation of the engine.
If you attempt to turn it against the normal rotation, in a clockwise direction, you will lock up the starter clutch and in turn rotate the starter motor which causes a huge amount of drag and resistance on the crankshaft.
Just sayin

[LC4CARL]

I remember way back in the day when there were RZ cup races.....we were watching when a bike came off the track flipped a few times and the throttle stuck open, it screamed for a bit and then "pop" it was gone......

Saw this happen to a snowmobile too.....a '67 16 horse Olympic that took off across the yard at full throttle into a bunch of saplings...by the time my brother got over to it, "pop." When he started it in the morning he had the habit of holding the throttle wide open while giving it choke......this one morning it didn't go so well.....

Years ago, my brother lent me his MX175 dirt bike for a long weekend with my buddies. In preparation I drilled many holes in the air box to "give it more power."

"Was that detonation I heard..?"

By the hole I put in the piston on day two, I would say "yes..."

Rejet the carburetor? Never heard of it...

[Bumblebee]

Years ago, my brother lent me his MX175 dirt bike for a long weekend with my buddies. In preparation I drilled many holes in the air box to "give it more power."

"Was that detonation I heard..?"

By the hole I put in the piston on day two, I would say "yes..."

Rejet the carburetor? Never heard of it...

A common occurrence in those days

My Kawasaki 250 triple burned a hole in its centre cylinders piston one time. Apparently my dad changed the spark plugs while I was off working the fields and mistakenly put a really hot plug in the middle hole, the other plugs were good

We had it torn down and a new piston in it the next day

That thing was so simple to fix