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Discussion Starter #1
My con rod let go today on the way to the gas station, died as soon as I hit the parking lot. Fired it back up and heard a low-toned knock and instantly suspected the crank. A truck ride home and an hour later, I found glitter oil, slight scarring on cylinder and piston, worn oil pump, a bad con-rod bearing and guessing from the bluing on the rod, the crank is bad too. No big pieces in oil strainer or spinner, everything else looks good.

Being I'm an experienced mechanic, I know better than to think I know it all, especially these little honda engines. Hopefully someone can help prevent a mistake or oversight.

My bike is a 2014 with a stock cylinder bored to 170 and a wiseco piston, approximately 60.4mmx61mm, pc5 and at, straight pipes and k&n filter.

I've got these in mind to fix it.

Koso 186cc bbk -$260
OEM oil pump -$17
OEM crank, con rod & bearing -$120
OEM crank bearing -$18

So, $415 to get her running again, already have oil and gaskets, anything else?
I plan on upgrading to 5spd, kitaco cover, kitaco pump, and forged crank/rod so the previously stated list is only to get her temporarily moving again.

Any ideas? Alternatives? Thanks in advance!!!!!
I can post pics of engine parts tomorrow if needed, anything to get a little help.

I already miss her.....馃槶馃槶馃槶
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Big bore but no oil cooler?

If you are going for more power with the big bore you have more heat and less metal to deal with it plus more internal crankcase pressure.

For a big bore you should add:
heavy duty oil pump
oil cooler
crankshaft support bearing
heavy duty cam chain tensioner and button
a little stronger clutch springs
correct temperature range sparkplug
appropriate tuning to stay cool

If you plan to do all of the higher performance parts later and just want to get it running, I'd do the parts that keep you from having to split the case later(upgraded transmission and crankshaft).

Put the rest stock for the time being to keep it cheap.
 

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Discussion Starter #3
Agreed,I was shopping for those too and came to the conclusion that I already have the required materials to make one considering the koso aluminum cylinder runs cooler and already has oil in/out. It had 90mi when it had the conversation, the guy I got it from says the build was pretty extensive, it never had an easy day in its life, and killed at 6k. If I can get another 6k for $500 with an oil cooler, I'm good until I get all the dreamy stuff, or a swap, or whatever. The bike's fate still isn't fully decided and I definitely don't want it to go slower in the meantime.

I will get the support bearing for sure, that would be the next purchase and it may already have valve train upgrades, I'll have to have a closer look.

Good stuff, thanks!
 

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Running a generic hydraulic slave with that Brembo clone master? Got pics of that?
 
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Discussion Starter #5
Hell yeah I do, and I love them. I got it for Christmas, was a little sketched out but after disassembling, inspecting, and reassembling, I decided to give them a shot and man, am I glad I did. In my opinion, it completely transformed my experience of the bike. I could go on and on, but yea, I freaking love them. The slave cylinder took a little fiddling with to get right but it works effortlessly now. We'll see how it holds up, my expectations are low tbh.
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Discussion Starter #6
So, you think"Ultra Copper" would be an acceptable substitute for the honda recommend crankcase sealant?
 

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Discussion Starter #8
No reason, just curious as I already have some, fresh tube. I'll order the honda stuff now.
 

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Discussion Starter #11
Oh, yea, I ordered all the parts yesterday, managed to get the crank support bearing too along with any specialty tools like spinner nut wrench, flywheel puller, bla bla bla.
 

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Discussion Starter #13
Yep, exhaust and high heat situations. I work on a lot of different types of engines so I usually keep the stuff all the time.
 

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Discussion Starter #14
Got my new crank in yesterday and am going to press the bearing into the case today. Got all the parts for my oil cooler and the crank support bearing and big bore kit show up tomorrow.

I purchased some Motul 4t 10w40 and it got me thinking, how does that oil compare to the v300 10w40 in terms of groms. Like, if you had to pick between the two, what would you suggest?
 

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Discussion Starter #16
Correct, and that is exactly why I picked it. This bike never has easy days, every day on the road is like a race day. I'm not going to lie to you guys, I'm really effing hard on it so I was guessing that maybe the racing oil would be better off. I am okay with changing it often, I just want to know if I will actually benefit from what this oil has to offer considering how hard I am on the bike.

I'll probably should have mentioned that in the beginning, LOL
 

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Discussion Starter #20
Considering I'm using the koso high flow oil pump, 40% more volume, do I need to enlarge the hole for this oil jet? The service manual says it's a 1 mm oil jet and I have precision drill bits, I'm wondering if I should open this up to 1.5 or 2 mm hopefully not at all, or should I start a new post?
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