Engine Rebuild

[crazymadbastard]

Originally Posted by n4mwd

If the carbon is thick, the best way to get it off is with rubber gloves and easy off oven cleaner. Spray, wait 30 minutes, wash off with water, repeat until its clean. If its not too bad, you can also use cleaners like purple, etc. Just don't forget the rubber gloves. It can take months for the skin to grow back.

And goggles!

[FvnnyL3tt3r1ng]

It's coming along! Had to extract 3 bolts tonight and they all went pretty smoothly; no broken drill bits.

I found out what the plastic piece I was questioning was for. It goes on the shift shaft as a spacer.

I just sheared off the bolt that holds the chain tensioner lever in place on the metal spacer. Can anyone explain to me why a bolt will continue to torque until it snaps when you have the proper torque set? Is it just worn?

Luckily I got it out and I'll just head to the hardware store tomorrow to get a replacement. Glad my threads weren't damaged because that's the whole reason I'm in this predicament in the first place!

Does anyone know what kind of metal I need when buying the replacements? I need bolts for the head that hold the top bearings of the camshafts on and the silver bolt I just sheared which held the tensioner lever in place.

Still curious why the engine was overheating in the first place as all the passages have been fine... Perhaps it was the oil itself? I do drive the bike very hard so who knows.... I'll be sure to order a new thermo switch this time as that is suspect in my eyes.

[FvnnyL3tt3r1ng]

Also, how do I re-torque that bolt that is on the alternator side of the crankshaft? The one you use to turn the engine over manually....??

[n4mwd]

I'm not sure why you are breaking off bolts. The bolts they use are special in that they break before damaging threads. So whatever bolt you replace it with needs to be soft steel. Don't use a hardened bolt.

Sometimes the bolts are damaged by overtorquing but don't break until later. It could also be that you are using the wrong scale on the torque wrench (ft-lbs instead of in-lbs, etc.). Or you are using the wrong torque value. Or the wrench isn't accurate.

The alternator bolt is only 50 ft-lbs and is pretty easy to torque. Just make sure the key is in place and all the starter gear stuff is there too.

[The_big_dill]

Originally Posted by FvnnyL3tt3r1ng

It's coming along! Had to extract 3 bolts tonight and they all went pretty smoothly; no broken drill bits.

I found out what the plastic piece I was questioning was for. It goes on the shift shaft as a spacer.

I just sheared off the bolt that holds the chain tensioner lever in place on the metal spacer. Can anyone explain to me why a bolt will continue to torque until it snaps when you have the proper torque set? Is it just worn?

Luckily I got it out and I'll just head to the hardware store tomorrow to get a replacement. Glad my threads weren't damaged because that's the whole reason I'm in this predicament in the first place!

Does anyone know what kind of metal I need when buying the replacements? I need bolts for the head that hold the top bearings of the camshafts on and the silver bolt I just sheared which held the tensioner lever in place.

Still curious why the engine was overheating in the first place as all the passages have been fine... Perhaps it was the oil itself? I do drive the bike very hard so who knows.... I'll be sure to order a new thermo switch this time as that is suspect in my eyes.

My cam cap bolts snapped twice, when i was tightening them, they didn't seem to get tighter, so i kept spinning, then POP, and half the bolt is stuck.

I believe this is due to "necking" of the bolt, where the threaded area literally stretches and arches.

Furthermore, i wouldn't buy anything from the hardware store to replace internal engine bolts. I got all my bolts from the dealer, yes it was a wait, but i can trust that when i put it back together, it was to manufacturer spec.

[FvnnyL3tt3r1ng]

I know to keep spare bolts on hand from now on at least. It's coming along quite well I'm currently just extracting ANOTHER screw. This time it is out of the water pipe where it attaches to the impeller housing. Got the head all together for the most part with valve clearances done. So much easier when the engine is in your bedroom instead of out on the street might I add. I just need to throw the shift shaft in and connect it to the gear drum and re assemble the clutch.

[FvnnyL3tt3r1ng]

http://www.motosport.com/motorcycle/..._-EX250/CLUTCH

Just wanna verify the thrust spacer part no. 92026 is facing the right direction. It's larger side is supposed to face outboard correct? Almost like if it was an arrow it would be pointing inwards towards the bike?

I don't have enough room to thread this nut on all the way onto the hub.... Not sure if that's just how it is..

2013-10-05 15.51.39.jpg

Edit: Nevermind the nut the oil pump gears weren't meshing. I still need confirmation on the thrust spacer sticking out all weird though.

[FvnnyL3tt3r1ng]

Just broke the clutch hub trying to torque the nut on. Anyone got a spare for sale?

part no. 13087

Does this piece spin freely in gear or does it lock? Is it safe to torque it with the bike in gear?

[n4mwd]

Your picture doesn't look right. Starting with nothing but the engine, you want to install...

1. Beveled washer with small end pointing into engine.
2. Cylinder shaped bushing with a snap ring.
3. roller bearings over that.
4. Clutch basket over that.
5. Rear clutch hub.
6. Washer
7. big nut.

The big nut is supposed to be replaced every time you remove it. Make sure the cylinder bushing thing with the snap ring is pointed the right way.

[n4mwd]

Originally Posted by FvnnyL3tt3r1ng

Just broke the clutch hub trying to torque the nut on. Anyone got a spare for sale?

part no. 13087

Does this piece spin freely in gear or does it lock? Is it safe to torque it with the bike in gear?

Oops. Did you break on of the tangs off? The nut gets 100# of torque so its kindof hard to overtorque that one.

The internal hub goes to the transmission and the outer clutch basket goes to the crankshaft. Also be careful not to misalign the clutch basket gear with the oil pump gear or else you'll bend the oil pump shaft and need a new one of those too.

[alex.s]

http://www.cyclegear.com/CycleGear/A.../p/36506_00000

[alex.s]

if it doesn't go down all the way the washer behind the hub is backwards or the oil pump isn't lined up

[FvnnyL3tt3r1ng]

Originally Posted by alex.s

oil pump isn't lined up

^^This

I didn't know about that clutch tool I'll have to pick one up!

[FvnnyL3tt3r1ng]

Originally Posted by n4mwd

Oops. Did you break on of the tangs off? The nut gets 100# of torque so its kindof hard to overtorque that one.

I had a hammer wedged in between the hub (where one of the 4 threads sticks out) and the block. This was too much torque for said hub (again where the 4 bolts thread into).

I could probably jb weld it back because it looks real weak in the first place...But I'll probably spend the $20 on an ebay one....

[FvnnyL3tt3r1ng]

Originally Posted by n4mwd

The internal hub goes to the transmission and the outer clutch basket goes to the crankshaft.

Is it safe to torque with the bike in gear or should I just buy the tool?

[alex.s]

100# is more than enough to move the engine (trust me i know this from trying it)

get the clutch hub vice ($10) and get an impact wrench ($25)

[n4mwd]

Actually, an impact wrench is good for removing it, but not putting it back. You need a torque wrench for that.

If you had it on the bike and had some way to put the brakes on, you could use the transmission to hold it. When I do it, I use my tool I made and then use a flat screwdriver wedged in between the crank and clutch basket gears to keep it from moving.

The main thing is that you need something to keep the engine stable.

If you are not in a hurry, I could come over some time with my tool. OR you could just buy one.

Clutch Tool

[cuong-nutz]

Use the clutch hub tool to hold your stator/flywheel/magnet thing. Expand the tool and have the tool hold it against the projections on the outside of that thing.

[FvnnyL3tt3r1ng]

Originally Posted by cuong-nutz

Use the clutch hub tool to hold your stator. Expand the tool and have the tool hold it against the projections on tye outside of the stator.

I think I understand what you mean but I'll have to look at my bike to see...

Are you saying to open the tool, place the lips of it on the outside of the flywheel, and then clamp down on/next to the projections?

[cuong-nutz]

Originally Posted by FvnnyL3tt3r1ng

I think I understand what you mean but I'll have to look at my bike to see...

Are you saying to open the tool, place the lips of it on the outside of the flywheel, and then clamp down on/next to the projections?

yessir.

[FvnnyL3tt3r1ng]

Ok I have no idea how to use that clutch holder tool. I'm researching it online right now. Not very intuitive.

I didn't get your idea either @cuong-nutz

[cuong-nutz]

They're like giant vice grips. If you don't know how to use vice grips, Lord have mercy.

Just for you Justin

Link to original page on YouTube.

[n4mwd]

Justin, I'm pretty sure that tool goes on the clutch hub side and not the stator. Holding the stator would not accomplish anything. It holds just the inner teeth and not the outer if I am not mistaken.

I plan to be near your neighborhood on Monday afternoon-evening. I can bring mine if you don't have it by then. Mine is different. Its the same one we used to get it off.

[cuong-nutz]

Originally Posted by n4mwd

Justin, I'm pretty sure that tool goes on the clutch hub side and not the stator. Holding the stator would not accomplish anything. It holds just the inner teeth and not the outer if I am not mistaken.

the tool clamps down on the teeth of the clutch hub to hold to still so you can tighten/loosen the nut. The same process can be used for tightening and loosening the flywheel too.

cheater way, but you have to be really careful or else you may break stuff.
http://youtu.be/pbvefUAupok?t=2m6s

http://www.youtube.com/playlist?list=PL00FC53212B9D0765

[FvnnyL3tt3r1ng]

Originally Posted by cuong-nutz

the tool clamps down on the teeth of the clutch hub to hold to still so you can tighten/loosen the nut. The same process can be used for tightening and loosening the flywheel too.

cheater way, but you have to be really careful or else you may break stuff.
http://youtu.be/pbvefUAupok?t=2m6s

http://www.youtube.com/playlist?list=PL00FC53212B9D0765

Sorry but I really need a picture lol.

I've already used an impact wrench on it but I'd still like to know what torque I'm at.

[FvnnyL3tt3r1ng]

Originally Posted by n4mwd

Justin, I'm pretty sure that tool goes on the clutch hub side and not the stator. Holding the stator would not accomplish anything. It holds just the inner teeth and not the outer if I am not mistaken.

I plan to be near your neighborhood on Monday afternoon-evening. I can bring mine if you don't have it by then. Mine is different. Its the same one we used to get it off.

I like yours a lot better it's a lot safer for that babybutt-soft metal kawasaki used for the clutch hub. I think I'll buy one for future use....

[cuong-nutz]

Originally Posted by FvnnyL3tt3r1ng

I like yours a lot better it's a lot safer for that babybutt-soft metal kawasaki used for the clutch hub. I think I'll buy one for future use....

You could just make your own with an old clutch steel plate and weld a handle to it or do what this guy did:

http://forums.ninja250.org/viewtopic.php?t=83912

Best picture I can find without me having to draw up my own!

[FvnnyL3tt3r1ng]

Originally Posted by cuong-nutz

You could just make your own with an old clutch steel plate.

This is true, but I don't have any welding skills or resources and I don't have any metal plates I have to give up.

[FvnnyL3tt3r1ng]

I started this thread on July 4th and it's now Oct 10th. Way to finish in a timely manner. D'oh

[cuong-nutz]

ninja edit!

[FvnnyL3tt3r1ng]

Originally Posted by cuong-nutz

ninja edit!

Pic is too small haha.

Is one lip on the outer basket and one lip on the actualy hub? If so I probably would have taken a while to figure that out....

[cuong-nutz]

Originally Posted by FvnnyL3tt3r1ng

Pic is too small haha.

Is one lip on the outer basket and one lip on the actualy hub? If so I probably would have taken a while to figure that out....

The tangs of the tool go on the hub itself. It does not brace against the clutch housing/basket.

Once you clamp it down on the hub, you hold the clutch tool or brace it against something to hold it still while you torque the nut down.



if that doesn't help I don't know what else will. lol

[n4mwd]

I thought I posted this before, but it must have been in another thread.
This is the one I made which closely mimics the EBC one.
It was made from a spare steel plate and the extra parts are
attached with aircraft rivets not welds.
Its perfectly acceptable to use little nuts and bolts too.



Its function is to lock the inner and out clutch hubs. Then all you have to do is lock the crank with a screwdriver and torque away.

Justin, did you already buy the cycle gear one?

[ninja250r81]

From reading this thread and others. Should have purchased a rebuilt exchange motor.

When people say that the motor has overheated and only replacing one or two parts in the first few posts.

You quickly realise not going to end well.

Guess not everyone has the skill and a family of engineers and an engine builder.

[cuong-nutz]

Originally Posted by ninja250r81

From reading this thread and others. Should have purchased a rebuilt exchange motor.

When people say that the motor has overheated and only replacing one or two parts in the first few posts.

You quickly realise not going to end well.

Guess not everyone has the skill and a family of engineers and an engine builder.

If you're on Ninjette.org you have all that and more!

Experience gained is priceless.

[n4mwd]

Originally Posted by ninja250r81

From reading this thread and others. Should have purchased a rebuilt exchange motor.

He did buy a replacement engine. He's just rebuilding the original engine for the experience.

[FvnnyL3tt3r1ng]

Originally Posted by n4mwd

Justin, did you already buy the cycle gear one?

Yeah I already bought it.

For some reason I thought yours was welded together. I don't have a spare metal plate anyhow.

[FvnnyL3tt3r1ng]

Originally Posted by cuong-nutz

The tangs of the tool go on the hub itself. It does not brace against the clutch housing/basket.

Once you clamp it down on the hub, you hold the clutch tool or brace it against something to hold it still while you torque the nut down.



if that doesn't help I don't know what else will. lol

Ok, I thought that's how you used it at first but in actual practice it doesn't seem the tool is big enough. Am I wrong on that? I think that tool was actually a bad recommendation I just don't think the metal is strong enough to be clamped down by anything. I broke the last one wedging something in between the grooves....

[FvnnyL3tt3r1ng]

Originally Posted by ninja250r81

Guess not everyone has the skill and a family of engineers and an engine builder.

Yeah, not everyone can be as superb as yourself. Don't pull anything patting yourself on the back too hard.

[cuong-nutz]

That tool I have is plenty strong and big enough. Unless you're clamping down very tight or have to cocked at an angle, I can't see how you would break anything.

How is the tool not big enough? Can you elaborate?