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Discussion Starter · #1 ·
My BBK engine blew up.

Where is the best place to source a new engine?



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Yikes! Sorry to see that Pard. If you're looking for a brand spanking new OEM stock engine I would start with your local Honda dealer parts dept. Maybe check Babbitts or RevZilla too.
 

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What happened exactly, Pard? Do you have more photos? I’m having trouble determining what exactly I’m looking at from that photo. Man, sorry to hear that. Is it a total loss? I would price parts at Partzilla too. They have been pretty good to deal with for me.

Edit to add: I think I better see now, that is the underside of the engine? Wow!
 

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Discussion Starter · #5 ·
What happened exactly, Pard? Do you have more photos? I’m having trouble determining what exactly I’m looking at from that photo. Man, sorry to hear that. Is it a total loss? I would price parts at Partzilla too. They have been pretty good to deal with for me.
The picture is of the bottom of the engine. The case blew out.

I need to tear it down and see what was damaged. I am expecting it to be extensively damaged.

Here is video of the moment of failure. Sounds of metal crunching ...

 

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Ouch. What a buzzkill. That hole in the case is no joke. It’s big. I wonder if the connecting rod broke? I would like to think you could rebuild what you have.
 
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Looks like the piston rod broke.

Good thing you didn't wipe out with the oil slick it put down.

Had friend years ago with an S10 pickup truck, small block engine swap with nitrous kit. Broke a driveshaft during a street night at the drag strip. Sounded like the whole engine bottom blew apart. The force of the two foot section of shaft still in the transmission flying around broke the entire bell housing and it whacked some brake and fuel lines. Lucky it didn't pole vault with the other 2/3 section dragging forward.
 

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Yeah, keep us updated. I always appreciate your contributions to the forum.

If you plan to keep running a 186cc kit, it might be a good time to install the Kitaco forged rod and crankshaft. It looks like the rod broke to me.

The connecting rod and crankshaft are two of the weakest links on these engines.
 
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Crazy, and my worst fear...
 

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Sorry to hear about that, can you remind me on your particular combo and how many miles were on it?
 
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Discussion Starter · #12 ·
4K miles since BBK installed. Never ran it over 9500 RPM. 5K total on the bike since new. Original owner.

So far I think it may only need a new spark plug! 🤣🤣🤣🤣🤣

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Lol, I'd swap spark plug brands. That one doesn't look too good.
 
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Discussion Starter · #14 ·
Lol, I'd swap spark plug brands. That one doesn't look too good.

It should buff right out and be good as new! LOL!

DHM BBK, Oversized intake and head, etc. All the usual goodies we put on until it blows up.

I should have put on the forged piston rod. I have yet to confirm that is the source of failure, but so far seems likely.

I figured if I kept the RPM out of the red it should be OK, but the extra power demands a better rod.
 

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4K miles since BBK installed. Never ran it over 9500 RPM. 5K total on the bike since new. Original owner.

So far I think it may only need a new spark plug! 🤣🤣🤣🤣🤣

View attachment 89816

View attachment 89817
Shame. New Takegawa 181 hot rod with 5 speed is 4k ready to bolt up.

Then you'd need brake and suspension upgrades plus oil cooler, tuner.
 

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It should buff right out and be good as new! LOL!

DHM BBK, Oversized intake and head, etc. All the usual goodies we put on until it blows up.

I should have put on the forged piston rod. I have yet to confirm that is the source of failure, but so far seems likely.

I figured if I kept the RPM out of the red it should be OK, but the extra power demands a better rod.
That’s funny. I was literally about to post, “That’ll buff out”!

I wish Honda would just put a stronger rod and crank in these bikes to begin with. I would be willing to pay $150-200 more for that up front. They know good and well, a huge portion of us are going to modify these bikes. I understand that not everyone would be ok with the increased cost, so maybe they should offer a model called the “Grom Pro” that has that option.

I have a feeling it won’t be too many more years and we are all going to be forced onto electric bikes.
 
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Discussion Starter · #18 · (Edited)
Well, the piston rod has vanished, probably exited through the crankcase.

May need a new head, cylinder and piston. Will try and hammer it out first. :ROFLMAO:

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Good grief! Well, that case could probably be salvaged with some JB Weld...:LOL:
 
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