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CBR300R Engine Swap

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I'm planning on swapping in a CBR300r engine. I found various scattered bits of info here on the forums and figured this might be a good place to consolidate info and ask questions of those who have done this.

@Cuttlefish Would love to hear your thoughts now that you've had your 300r engine in for a while.

Cuttle has a thread about his swap @ Advrider found here

My preliminary questions are:

  • To start with if I understand things correctly the 300r engine is a direct bolt on swap, do I have that right? Other than getting the engine I would need to source the throttle body and ECU for the 300r? Anything else or is that all I need to source?
  • I have an FMF header and pipe as well as an EJK, I think the header and pipe will be fine (let me know if not) but will I need to buy a new Dobeck EJK for the 300r or will my existing one for the L port across?

 

 

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  engine goes straight in  ecu throttle body  ditto 

...check if the crank recall has been done if you can  

you will need to extend  most of the wiring  ..easy enough   to do   

the  300 engine rides nice     ..i wouldnt bother with a feul controler  they   have little effect if any and    cause exceess feul  milage    ...drill and tap the head to put the 02 sensor back in  ..

the 300r gearbox is  actually pretty good    its shorter  gears low down are  closer together   and that  allows you to gear up     so that top gear  although  shorter than the 250s    is very usable and closer to fifth ..im able to use a final gearing of   15/39      which is  a big leap from the 14/43     on the 250...7 cogs in effect     so its a much less revvy affair    all round    ..its still more than usable off road     for sure   

the engine is way stronger lower down   loads more tourque   and   a sensible  practical cruising speed in the low 70s    .....  

http://32830846271_e47167bbe6_h.jpgDSC_0208 by minkyhead56, on Flickr

http://32524489865_03db2398eb_h.jpgDSC_0200 by minkyhead56, on Flickr

 

http://32371871322_2f82621c67_h.jpgDSC_0196 by minkyhead56, on Flickr

Edited by milkyhead
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Minky did his swap himself. Good job.

As a guy with limited mechanical aptitude and with no info on it being done, I left it in the hands of a mechanic.

He loved how simple it was. He needed to change the plug end on the wires from the stator.

CBR 300 throttle body and ecu used.

Nothing else changed. Used my FMF header and Q4 pipe. I don't have an ejk and don't feel like it needs it.

I'd install the engine and see how you like it. You could then either sell the ejk or contact ejk about whether they could reprogram yours. I recall that people using 250 controllers on their big bores, let's just say, ran into problems because of it, from memory.

I run 14/40 sprockets. 14/38 it revs less at 100 kph but softened the power delivery in the lower gears and I have now changed it back to ride with friends on enduro bikes.

As Minky said, loads more torque. 

What trips me out is my CBR 300 engine, ecu and throttle body cost $850 AUD.

That's cheaper than just a ejk and a FMF full system.

And I still have my 250l engine, ecu and throttle body to either sell or use as parts.

Also the 300 doesn't have the judder spring in the clutch or the big gap inbetween first and second like the 250.

 

 

Edited by Cuttlefish
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7 hours ago, milkyhead said:

...check if the crank recall has been done if you can 

Thanks for all the info milky. I read about that this morning. That got me a little nervous about snagging an engine off ebay.

2 hours ago, Cuttlefish said:

As a guy with limited mechanical aptitude and with no info on it being done, I left it in the hands of a mechanic.

loads more torque.

Also the 300 doesn't have...the big gap inbetween first and second like the 250.

 

 

I'm with you, I'll have a mechanic do it.

Torque is exactly what I'm looking for. Glad to hear that

I run 14/50 and rarely use 1st gear, that gearing makes 2nd good for just about everything at lower speeds (unless your in the tight slow stuff). You went with 14/40? What type of offroad riding do you do?

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Ride ADV stuff eg blacktop to gravel roads with 4 WD tracks when with guys on 600-1200cc bikes. Ride trail bike areas (enduro stuff) when with mates on Beta xtrainers and Husky 450s. 

Moderate stuff.

This video has a lot of local terrain like we ride but without the steep, super rutted hills with rock shelfs they are riding in the middle of the vid.

 

Use the existing loom for the swap. It couldn't get any simpler according to my mechanic.

Edited by Cuttlefish
Added video
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Just picked this up off Ebay, 2015, only 1350 miles.

s-l1600.thumb.jpg.8c77c1fba3f16753ebbd60dea3729f7a.jpg

 

 

Now I have to source the throttle body and ecu.

Edited by Kompact
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The same seller also had the throttle body and ecu from the same bike, snagged them as well.

595a838c6d400__12.JPG.8f2951cf2df855988f9c14725eaecc5b.JPGpp.JPG.b7faff62790ea6288fd927633b7a93a2.JPG

Edited by Kompact

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7 hours ago, Garth Knight said:

Nice, if you don't mind me asking what did you pay?

They were listed in USD and I'm in Canada, so about $5829945 CAD.

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That's awesome Kompact, good luck with the swap.

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A cooler showed up in the mail today! This engine is brand spankin new, 1350 miles on it and not a scratch. Looks like it just came of the production line.

20170719_173253.jpg.adf94fe58b4413f62b0f4633af1db95e.jpg

Let's get these drywall screws out of the lid and see what's inside. I feel like I'm 8 and it's Christmas morning.

20170719_173358.jpg.886b07cec89f477477e5fdfe44c2f45f.jpg

20170719_173704.jpg.346f714da0ae05b6c0e9e53697d9492c.jpg

 

The throttle body and ECU from the same bike

20170719_175643.jpg.418893ced65a6d6c564ce33a2b1a46fa.jpg

 

 

 

And the good stuff

20170719_174535.thumb.jpg.cf0b5c00d7f182641a6f23da2b9cb02b.jpg

20170719_174552.thumb.jpg.e4597950aa8db6402020ff5bc472db6e.jpg

Oh boy, oh boy, oh boy. I am soooo tempted to bring it over to the mechanics tonight but I have a big ride planned for Saturday and if something doesn't go right with the install I won't get to ride this weekend. I'll bring it to the mechanic on Monday, or maybe tonight, no I should wait till Monday.

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I am excited for you man, can't wait to ride it when you come over.... if you'll let me

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Whoever shipped it did a First Class job. Let us know how you like it when it is done.

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A friend and I did the swap on my bike ourselves in less than 10 hours. It ought to be quick and simple for a mechanic who actually knows what he's doing.

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Nice mott555, you're braver than I am. For you and Cuttle, what did you guys do with the O2 sensor and pair valve? I was reading mixed things on some forums for the CBR300R about those two. Some people were saying it ran too rich with the O2 sensor so took it out and others said the opposite.

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My mechanic is modifying the exhaust header for the O2 sensor for me while putting new tires on. It seemed to run fine without it but I occasionally got check engine lights. The PAIR valve didn't need anything special, it hooked up fine. My evap canister is not entirely hooked up because the CBR300R engine did not have the vacuum port for it.

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