[Tamir]

Did you physically see the break

It's less a matter of seeing, it's more a matter of what kind of experiment he conducted to reach his dramatic conclusion. After all, it is impossible for a stupid fall to damage the crankshaft, it is impossible. And we saw the video...I don't believe the diagnosis that a general overhaul is needed because...
Sorry, I don't believe it.

Maybe this is fate's way of telling you it's time to upgrade!

Cahuna, why to upgrade? The good guy just now bought his motorcycle.

Hi new here with a 2013 bike I just bought.

 

[Bonificus]

Sorry to hear that.

Did you physically see the break or did a mechanic tell you the news? Looks like an engine shipped is about $1,200. Not sure what a broken cbr250r in your neighborhood is worth, but maybe you can get $1000 or so for what you have. Maybe this is fate's way of telling you it's time to upgrade!

A mechanic told me the news, I will take it apart when I replace it to verify the prognosis but my only option is to replace it myself. Despite questions that may still remain, I am in need of the answer to this: how difficult is it to replace the engine with a 500R of the same year?

 

[Big Cahuna]

A mechanic told me the news, I will take it apart when I replace it to verify the prognosis but my only option is to replace it myself. Despite questions that may still remain, I am in need of the answer to this: how difficult is it to replace the engine with a 500R of the same year?

Replacing a 250cc engine is much easier than cracking open an engine and repairing it. A few water hoses, cables, sensors, and mounting bolts should do it. This is a small engine, you should be able to do the job by yourself. I wouldn't mess with the 500cc engine. Even if it were possible the frame wasn't engineered for double the power.

It's winter, you should be able to find a 600cc bike for little money.

 

[Tamir]

Even if it were possible the frame wasn't engineered for double the power.

"Even if"??? With a disk and an arc welder it is possible.
Customization is an art where many things become possible there.

Is there any point in this, replacing a 250 engine with a 500 engine????
Only our friend can determine, this is his project.
If he says yes, we would appreciate if he remembered to share with us pictures of the finished product.

The guy is asking if the frame suitable for 500 cc, so:

• it doesn't fit in strength (Requires reinforcements),
• it doesn't fit in terms of the docking points (Required customization)
• and the head of the 500 cc engine, which includes two pistons in parallel, in my opinion is too wide and will not fit into the space in the frame of the 250 (But, and again, that not something that disc and welding arc can't be solve).

 

[Big Cahuna]

"Even if"??? With a disk and an arc welder it is possible.
Customization is an art where many things become possible there.

Is there any point in this, replacing a 250 engine with a 500 engine????
Only our friend can determine, this is his project.
If he says yes, we would appreciate if he remembered to share with us pictures of the finished product.

The guy is asking if the frame suitable for 500 cc, so:

• it doesn't fit in strength (Requires reinforcements),
• it doesn't fit in terms of the docking points (Required customization)
• and the head of the 500 cc engine, which includes two pistons in parallel, in my opinion is too wide and will not fit into the space in the frame of the 250 (But, and again, that not something that disc and welding arc can't be solve).

I'm pretty confident he is no engineer. I wouldn't encourage him to kill himself.

 

[Bonificus]

I'm pretty confident he is no engineer. I wouldn't encourage him to kill himself.

I may not be but my roommate is.

 

[Big Cahuna]

I may not be but my roommate is.

Be safe! Custom motorcycles are difficult to build well.
I too would like to see if a 500cc will work in a 250cc frame. I'm predicting that 2nd cylinder isn't going to fit.

 

[Tamir]

I may not be but my roommate is.

You'll forgive me for being a snooze, you still haven't convinced me that your 250 cc engine has exposed to significant destruction event. In my opinion, you have a good engine, and your problem is of the type:
No charging, and it has already destroyed one of your batteries.

Besides, it doesn't require special engineering design, and may fit the frame, it's the CBR300R engine. If this seems an interesting direction to you, there is a lot of information on this in the forum, use the forum's search engine, look for information there, here is an example of such a thread:

From 250 to 300 swap

I got a good deal on a 2013 cbr 250 with a blown motor. I happened to have a 2015 300r motor. I put the motor in the bike and runs and drives, but I read that it wouldn’t be right without the 300 ecu, so I bought the ecu from a 300 off eBay, I got it today, plugged it in and it fires right up...

www.cbr250.net