Top End Teardown - CRF300L Big Bore

[@121omfg]

I haven't seen your channel pushed in YEARS it's great to see you so active still!

[@EnzoGiovino]

I thought the same... came up in suggestions 🎉

[@schrodingersmechanic7622]

It's really cool seeing such in depth teardowns. I've been a car guy my whole life, recently got into bikes and it messes with my head thinking how hard these little engines work and how long they last. I'm just humming along 4-5-6k rpm cruising through town when it would sound like all hell is breaking loose if I did that in my vette. Loving the vids, don't have the gumption to tear into mine like that. Looking forward to seeing this come together.

[@TheGardenSnake]

It is pretty wild how these smaller engines just handle that so easy. And if you go smaller it gets crazier. Like when I was into nitro rc and the engines ideal around 6k and can rev to 50k. 🤯

[@yammienoob]

Make thing bigger, go boom better. Easy

[@Michael_Shay]

I rebuilt a CRF250L engine with my Uncle late last year, and it was in pieces when we started so we had to start from zero. It's all together now and running just fine but it would've been nice to see videos like this. Although I wasn't doing a big bore, it's nice to see videos that are well filmed and do a good job of explaining. A lot of this information applies to a top end rebuild. Thanks for putting this kinda stuff out there Jake, been watching you since middle school.

[@M.C.A.T.]

Brilliant. Thanks! There's a top end in my future and this is a great resource.

[@TheGardenSnake]

Glad it was helpful!

[@remid161]

I've been following your channel for a long time and have never ever said that any one of your videos were "boring", but if I was going to, wellll.... this might be the one :P

[@mikeskidmore6754]

Exhaust Polished .. Intake a little rough for vaporizing ..

[@marcochavanne]

Looking forward to hitting Barnwell Mountain and seeing how my bike with the cams, velocity stack, and tune compares to yours with the built head and big bore.

[@TheGardenSnake]

Yeah I need to get out there. I should take the crf in adventure spec when it’s done. Ride out and camp. I think you’ll like it with those mods. Made mine a lot more fun off road.

[@leadsled8961]

If you use riffler files you can see what needs to straightened and slow enough not to make a mistake. No die grinder can do what Tool and Die tools can do.

[@aaronbehindbars]

I love that you inset a clip from @IchibanMoto and it reminds me how much I miss seeing new content from him.

[@TheGardenSnake]

Best videos ever

[@OnThrottle]

Can’t wait to see how this all turns out. Amazing that you manage to work on it with a small human jibber jabbering in the background too!

[@Tx7sleepyjoe]

The shhh when using a impact on head bolts lol.. if you know you know.

[@hayukeen1127]

The ending made me smile :)

[@hydroboy35th]

Thanks for putting this out there! ✊🏻

[@DashRendar308]

I think the steel sleeves are more durable, when it comes to dirty, old and cheap oil and long standing periods, becaues I read somewhere that the sulfur in old oil will react with the coating on the aluminum cylinders and it will then wear of unevenly and could even destroy the engine way before its time.

[@TheGardenSnake]

That definitely can be true

[@greenmoto]

Another great video. Love the little frame that was sneaked in. Definitely something Tyler Durden would do. 😄🤘

[@marcelpursche5339]

If your are interested you could trace the profile of the cams yourself with a dial gauge and a "crank degree wheel" (you can build one yourself by printing one out and putting it on a piece of cardboard and ). You put the dial gauge on the top of the valve to measure the current lift (0 position is when it is fully closed) and slowly rotate over the engine. You then just write down the valve lift at a certain crank degree(e.g. one measurement every degree or every 5 degree depending on how exact you want to be). You can put the measurements in Excel and create a nice line diagram from the cam profile. That way you can get the open duration of the intake and exhaust cam as well as the overlap of intake and exhaust.

[@Pinetreemoto]

I swear Jake I could watch you rebuild a washing machine and still be entertained 😂 keep those caveman eyes sharp

[@TheGardenSnake]

Will do

[@-RyN-23]

The 300 head is strengthened if you look on the left side between the humps the studs would be going threw. There is extra webbing

[@TheGardenSnake]

On the outside?

[@ianm432]

It was so annoying to get it paused to read that. I had to set playback speed to x .25 lol but on the bright side it sounds like you're super drunk with the speed that slow so that was hilarious

[@garrettsharp89]

I couldn’t even pause it at .25, I had to screen record then do a frame by frame. 😂

[@M.C.A.T.]

You can use the comma and the period on your keyboard to advance or reverse one frame at a time.

[@TheGardenSnake]

Shhh 😂

[@doobielawson702]

​@M.C.A.T. ok Techboy, what about those of us who watch on a tablet 🤔 😀

[@westtexasrollin6559]

​@@doobielawson702or phone. Even worse, I usually watch on a TV. I haven't even been able to figure out how to change the playback speed on tv

[@dyi01]

You should get in contact with Black Widow Dyno in San Antonio to tune your bike after it's been assembled.

[@TEEDUBS]

I need to get me some of that consistent Jake feel MMMMMHHHMMMM

[@hickokaviation2249]

Awesome videos!

[@westtexasrollin6559]

If you're going to drive a long way to get coated, take it to Dan. He has this strange new purple color, and that gigantic oven. And he can make you a kewl new license plate ring for it

[@dyvrs3rips305]

Did you upgrade the water pump for the big bore ?

[@TheGardenSnake]

I would if they made one. Hopefully the cooling system it has will be enough. I’ve been keeping a look out for an oversized radiator. Once someone makes one I’ll get it.

[@2WheelPursuit]

Could you in theory do the exact same big bore with a CRF250L? Not that I plan on doing it, but I'm just curious if that bike basically has the same sleeve and same big bore capability.

[@TheGardenSnake]

Yes sir. The top end it the same as a crf250l. You would end up at 263cc.

[@2011cardinal]

BIG BORE!

[@spikejnz]

Ah yes, the good old German torque specs. Gutentight.

[@Fee.1]

What do you guesstimate your power numbers to be after all of this

[@ajseusa1488]

The longest lasting aluminum cylinders have a chrome steel sleeve, any of the coatings types applied directly on the aluminum cylinder never last anywhere near as long. Jake what have you been smoking?

[@TheGardenSnake]

🤷‍♂️

[@agileep]

Ok so the crf300l has a Cbr motor. So why couldn’t we just drop a Cbr 600 into a African body to get the street bike maintenance cycle? I only said African because it’s a bigger bike so maybe a bigger engine bay? I was just wondering what problems you might run into? Wire harness compatible maybe? But couldn’t you just splice everything? Sort of a Frankenstein build but make it look legit? Don’t know bikes but know engines. In theory it would work but fit and finish idk didn’t measure anything.

[@ConfusedRaccoon]

How easy/hard is a headgasket change on a 125 sm? 2 hour job or just give it to the mechanic for the week and overpay?

[@TheGardenSnake]

Two stroke? That’s like a 30 minute job.

[@ConfusedRaccoon]

@@TheGardenSnake 4 stroke, just one of those little 125cc yamaha engions. Its carbureted too. I'#m assuming I'll need to drain the coolent and oil and then do something about there being fuel in the oil.

[@moparman44069]

What are you getting it bored out too and where did you get the piston at because I have a CBR 300 and there not much aftermarket support

[@kennetknudsen7042]

Jake got Mercedes tools there

[@TheGardenSnake]

😦 wut

[@kennetknudsen7042]

@@TheGardenSnake 1:40 looks liek a merc logo on the ratchet

[@Fee.1]

Ari ported your head? Why is he being brought up? Just confused

[@willfest]

Can you show us dyno results after this? I am thinking pretty nice gains... not sure how long those nubs will last though.. curious how much valve clearance you will have between the valves and the piston or does the new piston account for that? Very interesting.. will you need to remap the ecu after this?

[@TheGardenSnake]

I will dyno tune it when it’s done.

[@willfest]

@@TheGardenSnake I have been very curious about this bike and have been mulling over first the 250L (until this came out) vs 650L vs drz400 but each one has something I dont like. 650 has small tank and poor fuel economy, drz has tall 1st gear, crf has squishy suspension. If they could just make a legit 400cc that has a short 1st gear, a 2nd gear that makes sense, and kind of a regular 3rd & 4th, 5th and a tall 6th so 65mph was low rpm and you could go up hills at 65 mph in top gear.. but you could wind it up if you wanted. Dont really care about top speed but ability to do lane changes anywhere would be nice. I dont think hi speed braking on a bike this tall and light on asphalt is all that safe which is probably why dual sports dont tend to go all that fast by design. I think they would really have something a lot of riders would want if they did this, and they may not move on?? I know theyd have to charge like 2k more to do that and have a decent adjustible suspension, nice big fuel tank and similar oil change and valve intervals. Would be well worth it. I dont want a ktm myself. Or a tenere 700 etc. I feel like if the crf isnt enough then the answer is the cbr. I enjoy watching your shows

[@TheCrutiaolaggo]

My card keeps declining on patreon so I'm gonna have to get a credit card. Still waiting for Yamaha to release their 250 replacement, maybe even Suzuki will do something in the sub-750 area and get something cool out there. Oh well I'll just get a DRZ and put a lectron on there someday

[@stuntsalami]

Heyy man, you can tell us how much miles are on this engine? So we have a point to know how reliable this is🤷🏼‍♂️ now you say yeaaah this engine is like new, but maybe it has only 500 miles on it so its not mind blowing😂😂😂

[@TheGardenSnake]

It’s got around 3k miles

[@JohnnyBoy919]

I don't get why honda couldn't just make it 300cc instead of 286. I would bet that they will when emissions get tighter.

[@TheGardenSnake]

So the older version was a 250 right. They took that and changed just a few small things to make it a “300”. The piston and cylinder are the exact same. So basically keep the R&D down as much as possible. This is a budget bike after all.

[@JohnnyBoy919]

@@TheGardenSnake It's not really a 300 though, it's 286. With you doing the big bore, will that make it true 300?

[@j.r.arnolli9734]

@@JohnnyBoy919 / 301cc 😎

[@9milsOn2wheels]

Don't stick your fingers in there, hay early heads up, will be up your way in September, will likely drag my bike with me.

[@ericunderwing]

PLEASE DYNO !!!!!!

[@TheGardenSnake]

Well yeah I’ll have to for tuning

[@ericunderwing]

@@TheGardenSnake will be interested video I did all this work to a drz 400 so it was a 462 and it kept blowing head gaskets. Hopefully you don't find the limit

[@galmi]

one company in Thailand can do 38 hp from same big bore upgrade. Let's see what will be here.

[@Jj12915]

Did you supply the machine shop with the piston you are going to be using so they can size the bore perfectly? Maybe you said that and I missed it.

[@Jj12915]

Yup you said it, three seconds after I posted this comment lol.

[@westtexasrollin6559]

Even gonna get them to Gap the rings. Lol

[@Fee.1]

That doesn’t look like a professional honing video

[@petertaylor2148]

That's not a big bore... My 357 cc is a Big Bore ... 😂😂😂😂

[@TheGardenSnake]

Did you see the first video on this? I talked about larger big bores and piston slap with these engines. 😬

[@Jeredsmith]

A lot of cave man work going on 👉👌🤏 yep feels smoother and bigger.