Cause of losing #3 rod bearing.

[SLEEPERBUSA]

1441cc, stock crank, lightend, balanced. Wossner rods, high pressure valve and gear. No other oiling mods, Mobile 1 oil. I don't remember clearence specs, but can assure that it was within factory specs at the time of build.
I ate #3 rod bearing.
I'm curious as to your opinions as to why the bearing may have gone south.
Thanks in advance!

[sportbikeryder]

What were you doing with it when it went?

[SLEEPERBUSA]

I think it started when I was in S.Florida. Tuning on some 9/10ths passes. On the motor.
No spray, but the guts were hung out quite a few times in a row. 

My last pass was several MPH off.


http://www.youtube.com/watch?v=ku2yKOdhbsU

[STREETDRAG]

DETONATION IS A BIG KILLER,LIMITER RIDING.....WHERE INJECTORS CLEANED AND SPEC'D WHEN BUILT?

[SLEEPERBUSA]

I can buy detonation because I had my head up my ass and had the wrong fuel in it..........I think??
I was at about 13:1 and had MR12 in it.

No, injectors were not cleaned or spec'd.

[SLEEPERBUSA]

I guess I'm trying to rule out an oiling problem. When we have oiling issues on GENII Busas, is there any one bearing that usually gets targeted first?

[gixxre750]

#1 is the most common. Furthest away and last to get oil

[sportbikeryder]

None of them are necessarily more prone to failure in my experience. I had an oil pickup that was sucking air earlier this year and went through 3 motors. I am not sure I ever had an issues with #4 and I have seen quite a few holes in #3 from others.

How much time was on the engine?

[Competition CNC]

Can you post what all your main and rod bearing clearances were for us?
What weight oil was it running?
Did you have an oil cooler on it?
Can you post high resolution and clear closeup pictures of the other 3 rod bearings?

I'll try and see what caused it.

[RansomT]

I can buy detonation because I had my head up my ass and had the wrong fuel in it..........I think??
I was at about 13:1 and had MR12 in it.

No, injectors were not cleaned or spec'd.

Don't think MR12 would cause detonation with a decent tune at that CR.  MR12 has a pump equivalent of 93 octane.   However, sometimes damage to rod bearings show up at a later date.  How long before this were you spraying nitrous?

[SLEEPERBUSA]

Can you post what all your main and rod bearing clearances were for us?
What weight oil was it running?
Did you have an oil cooler on it?
Can you post high resolution and clear closeup pictures of the other 3 rod bearings?

I'll try and see what caused it.

Well, unfortunately, The documentation got discarded, so I don't know the spec, but you know who built it...........He was so thorough and triple checked EVERYTHING, so while I don't know the exact numbers, I am 100% confident that it was within factory spec.....if that helps any??? 
I can check the remaining specs as I take it apart if that helps?


10W-30 Mobil 1.
Yes, full stock cooling setup, water and oil.
I'm not completely torn apart and am working so much that I won't be able to get pictures until this weekend, but I WILL get them and post them. Thanks...

[SLEEPERBUSA]

None of them are necessarily more prone to failure in my experience. I had an oil pickup that was sucking air earlier this year and went through 3 motors. I am not sure I ever had an issues with #4 and I have seen quite a few holes in #3 from others.

How much time was on the engine?

I only had a few months run time. Probably less than 500 miles.
3 heat cycles, dyno time, some drag strip time and 17 9/10th runs. 

[SLEEPERBUSA]

I can buy detonation because I had my head up my ass and had the wrong fuel in it..........I think??
I was at about 13:1 and had MR12 in it.

No, injectors were not cleaned or spec'd.

Don't think MR12 would cause detonation with a decent tune at that CR.  MR12 has a pump equivalent of 93 octane.   However, sometimes damage to rod bearings show up at a later date.  How long before this were you spraying nitrous?

Their rating has it at 87 octane, so that's what I was going by???
This engine never saw nitrous. It was always all motor.
It produced very good 1/8th and 1/4 mile MPH for me, so I want to get it back just like it was. 

[sportbikeryder]

None of them are necessarily more prone to failure in my experience. I had an oil pickup that was sucking air earlier this year and went through 3 motors. I am not sure I ever had an issues with #4 and I have seen quite a few holes in #3 from others.

How much time was on the engine?

I only had a few months run time. Probably less than 500 miles.
3 heat cycles, dyno time, some drag strip time and 17 9/10th runs. 

Wow...I guess definitions of how much run time are relative.

17  mile LSR runs, drag strip, dyno, and ~500miles street time. I am pretty sure it wasn't a build error

[SLEEPERBUSA]

I'm confident that it wasn't build error.  That is just my opinion tho. I'm just hoping to find an issue so I don't repeat it.
The 500 miles was probably combined miles. The 17 runs were in one day also........
I'm 260 pounds suited and the bike carried me 127mph in the 1/8th, and 157mph in the 1/4 at stock weight, gearing and clutch, at only 64", so I'm wanting to put it back together just like it was.

[RansomT]

I can buy detonation because I had my head up my ass and had the wrong fuel in it..........I think??
I was at about 13:1 and had MR12 in it.

No, injectors were not cleaned or spec'd.

Don't think MR12 would cause detonation with a decent tune at that CR.  MR12 has a pump equivalent of 93 octane.   However, sometimes damage to rod bearings show up at a later date.  How long before this were you spraying nitrous?

Their rating has it at 87 octane, so that's what I was going by???
This engine never saw nitrous. It was always all motor.
It produced very good 1/8th and 1/4 mile MPH for me, so I want to get it back just like it was. 

87 Motor Octane.   AKI (what USA pump standard uses) is 93.

[SLEEPERBUSA]

Got ya. Thanks
 

[canadian john]

How are the rest of the bearings?

[SLEEPERBUSA]

Don't know yet. I'll split the cases this weekend and get a better look. #3 is obvious tho.
There's daylight.
 

[canadian john]

Well get on it eh.............

[sportbikeryder]

Check the oil pump pickup when you have it apart.

[SLEEPERBUSA]

It was secure, but full of brass shit.

[SLEEPERBUSA]

[SLEEPERBUSA]

[Johnnnycheese]

. What am I looking at