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ANYONE can do this by following instructions in manual. That's how amateur mechanics LEARN to become better amateur mechanics. If you never learn anything new, how will you get better? Manual is excellent and can guide brand-new mechanics who've never done any of this work.
Agreed.
A mechanic in a shop is doing the same exact thing their first time, too, by looking over a manual to see how it's properly done. It goes without saying that it's always better to learn on a cheap, already broken motorcycle than an expensive one.

I don't know how many times I've put off a repair thinking I would destroy it then understanding afterwards how easy it was to do. I have undoubtedly saved Tens of thousands of dollars by doing my own work. There are some jobs that will require special and prohibitively expensive tools to repair and those are the jobs I hand over to a certified mechanic.

Don't forget that these machines were engineered and built in a way that could be repaired by less-than-brilliant people... except maybe those that put their filters on backwards :whistle:
 

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The disassembly is easy
At CBR250R:
  • Is it easy to disassemble a valve cover with an engine inside the frame?
  • Is it easy to disassemble the engine from the frame?
So "easy" is a relative term. These two tasks are difficult for me.
 
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Don't forget that these machines were engineered and built in a way that could be repaired by less-than-brilliant people... except maybe those that put their filters on backwards :whistle:
:love::coffee::LOL:
 
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Discussion Starter · #25 ·
I would do a couple of things before junking it.

Pull the valve cover and take a look at the cam lobes for galling or heat discoloration.

Remove the oil and filter, and check the particle screen (not sure where that is, or how to get to it) for metal flakes. If you see bronze-colored flakes - it's toast.

Try to locate the area where the ticking sound is originating. Is it up high, or at the base of the engine?

An issue with the valve train will produce faster ticking up high, an issue with a rod bearing will be more of a slower knocking and come from the center of the engine. Rev the engine up and down to about 3000, and hold it around 2500 or so, when listening.

Chances are things are not good, but I'd check it out before making the call.
Hey bro thanks for your help, i drained the oil and checked the filter and there’s no particles.

Also the sound comes from the top of the engine.
It is definitely not the rod bearing.

im goiing to open the cover right now. Do you think replacing the camshaft will do it?
 

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i drained the oil and checked the filter and there’s no particles.
But the chips are in the strainer and not in the oil filter. Your stubbornness is important and useful, provided you invest it in the right direction. To get to the strainer you have to open the right engine cover, which is a job that requires not only patience, but also more skills.
I promise you that you will find there what you are looking for(metals chips). (LINK),
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According to the noise you describe, here:
and it sounds like a tick that gets louder and faster in higher rpms
I also assure you that the crankshaft bearings OR the connecting rod bearings, one of them must be destroyed.
Maybe both?
 
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P.S. Regarding the camshaft, this thread also ran here in the forum lately:
The camshaft does not have a separate bearing,
the entire mount is its bearing.

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Usually the top end is the first thing to cook. As stated, if that's scorched the machined surface on the head where the cams lie, it's time for a new engine. Indeed, as a cheap bike, it's relatively easy to work on and if you confirm it's torched, no better way and cheaper way to learn. These repairs can be done yourself if in relatively decent shape; the engine isn't that heavy.

Right now, there's a complete engine on fleabay for ~$400 plus shipping, and if the damage is mostly isolated to the head area, there's a cbr300r cylinder head on fleabay for $129.
 

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Hey bro thanks for your help, i drained the oil and checked the filter and there’s no particles.

Also the sound comes from the top of the engine.
It is definitely not the rod bearing.

im goiing to open the cover right now. Do you think replacing the camshaft will do it?
I would start with that. Post a photo of what you find.

It's unlikely that everything will be fine, but you need to know for sure.

As Tamir noted, the screen under the side cover may be holding the damaged bearing particles, so you do need to pull the cover to check (after draining the oil). It is the only way to know the extent of the damage to the bottom end bearings. Disassembly shouldn't be overly complicated, but you may need to reference a shop manual online if you have questions.
 

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As Tamir noted, the screen under the side cover may be holding the damaged bearing particles, so you do need to pull the cover to check (after draining the oil). It is the only way to know the extent of the damage to the bottom end bearings.
Only in this case, again, according to the noises that described, we are not in a situation of maybe,
for sure there are chips in the strainer, a lot of chips.:coffee:
To remove the right engine cover it is not enough to drain the oil, it is also necessary to drain the coolant, this is a job that requires a lot of knowledge and experience (relatively).
 
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Only in this case, again, according to the noises that described, we are not in a situation of maybe,
for sure there are chips in the strainer, a lot of chips.:coffee:
To remove the right engine cover it is not enough to drain the oil, it is also necessary to drain the coolant, this is a job that requires a lot of knowledge and experience (relatively).
Not much to lose for trying at this point then.

Draining the oil and coolant doesn't take an experienced technician, and neither does removing the cover.

We know, for sure, what we will find?
 

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Draining the oil and coolant doesn't take an experienced technician, and neither does removing the cover.
JVK It's nice that you are so optimistic, or maybe everything seems so easy for you, the job of removing the right engine cover on a CBR250R(2013) is relatively complicated:
  • You need to drain both: the oil, and the coolant.
  • There is an issue with the clutch mechanism, and the spring. You have to keep the spring from falling into the engine, and then there is a problem of putting it back in place.
  • In the assembly there is an issue with the axis angle of the water pump.
  • In addition to the paper gasket, you need to replace 3 more O-Rings in three different sizes:coffee::whistle:
  • Draining the coolant is easy, but you mustn't forget to bleed air bubbles when refilling.

But hey, do you remember? That cover, in that particular case, is not going to be assembly for some time, because the crankshaft bearings need to be replaced:whistle::coffee::coffee::coffee:
 
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JVK It's nice that you are so optimistic, or maybe everything seems so easy for you, the job of removing the right engine cover on a CBR250R(2013) is relatively complicated:
  • You need to drain both: the oil, and the coolant.
  • There is an issue with the clutch mechanism, and the spring. You have to keep the spring from falling into the engine, and then there is a problem of putting it back in place.
  • In the assembly there is an issue with the axis angle of the water pump.
  • In addition to the paper gasket, you need to replace 3 more O-Rings in three different sizes:coffee::whistle:
  • Draining the coolant is easy, but you mustn't forget to bleed air bubbles when refilling.

But hey, do you remember? That cover, in that particular case, is not going to be assembly for some time, because the crankshaft bearings need to be replaced:whistle::coffee::coffee::coffee:
As I said before - reassembly is the part that takes the skill.

It is very possible that reassembly won't be required after the inspection...
 

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Discussion Starter · #36 ·
Usually the top end is the first thing to cook. As stated, if that's scorched the machined surface on the head where the cams lie, it's time for a new engine. Indeed, as a cheap bike, it's relatively easy to work on and if you confirm it's torched, no better way and cheaper way to learn. These repairs can be done yourself if in relatively decent shape; the engine isn't that heavy.

Right now, there's a complete engine on fleabay for ~$400 plus shipping, and if the damage is mostly isolated to the head area, there's a cbr300r cylinder head on fleabay for $129.
I opened it bro and the intake cams shaft is scratched and also where I lay the intake camshaft is scratched badly as well. If I put a new intake camshaft it will just get scratched or what do you think?
 

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Discussion Starter · #37 ·
I would start with that. Post a photo of what you find.

It's unlikely that everything will be fine, but you need to know for sure.

As Tamir noted, the screen under the side cover may be holding the damaged bearing particles, so you do need to pull the cover to check (after draining the oil). It is the only way to know the extent of the damage to the bottom end bearings. Disassembly shouldn't be overly complicated, but you may need to reference a shop manual online if you have questions.
I would start with that. Post a photo of what you find.

It's unlikely that everything will be fine, but you need to know for sure.

As Tamir noted, the screen under the side cover may be holding the damaged bearing particles, so you do need to pull the cover to check (after draining the oil). It is the only way to know the extent of the damage to the bottom end bearings. Disassembly shouldn't be overly complicated, but you may need to reference a shop manual online if you have questions.
I would start with that. Post a photo of what you find.

It's unlikely that everything will be fine, but you need to know for sure.

As Tamir noted, the screen under the side cover may be holding the damaged bearing particles, so you do need to pull the cover to check (after draining the oil). It is the only way to know the extent of the damage to the bottom end bearings. Disassembly shouldn't be overly complicated, but you may need to reference a shop manual online if you have questions.
This is what I found bro the intake camshaft is really scratched and the surface where I lay the in cam is scratched badly too.


when I drained the oil the oil did not look burned and it did not have any particles, also the motorcycle was able to drive, if the crankshaft bearings would’ve been destroyed do you think the motorcycle would’ve been able to run?

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What about cleaning it up ? Like sanding out the scratches? What do you think about that
You can't safely take more metal away, it's a moving part with a precise fit. Even if milled smooth the cam will just scour and bang against the journals until it destroys itself. You might smooth and polish it but you'll probably not get more than 500 miles out of it. Bits of metal will continue to flake off and enter other parts of the engine. I'm pretty sure it's heated itself super hot and annealed itself as it cooled.

How does the piston and cylinder look? If it's smooth and moving freely, it's just the cylinder head. I looked on ebay and I don't see one available. I'm guessing one can be found at around $50 if you're patient enough to wait for one to pop up. If it's an emergency and money is no object you could just go with a whole used engine. Poke around in there a little more, maybe remove the cylinders and see if there is more damage before you begin buying parts. Usually you can get an engine rebuild kit with all the gaskets but I don't seem to see one. You might look into seeing if one is available.
 
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