Bullet Proof Bottom End?

[slob]

Check this out, this motor was running but was making a noise like big end bearing, louder at higher revs.

[slob]

looks fine eh? how about this shot......yep busted the crank.. this is an 1100g motor that was recently rebuilt (not by me) and was running in an outfit. I had just crossed Australia and was heading home (10,000km in 10 days) but after only 6000kms it started making noise.

[Steve]

Yep, still "bullet-proof". \\/


Hey, some bullets are bigger than others. 8-[


.

[drhach]

I had Harley do somehting similar. One of the rods broke in half. It broke right below the wrist pin though, so when the cylinder fired, the piston skirt would cover the broken end and not allow it to go through the cylinder. It broke at about two in the morning on a lonely highway and it was LOUD. I'd passed a cop a while back and he heard it go. I shut it off. The damned thing fired right up when I kicked it over though, it still ran. Obviously I couldn't ride it home, but I wsa damned impressed. I guess it all depends on where the failure occurs.

[Billyboy]

Unreal! That was running?

[49er]

looks fine eh? how about this shot......yep busted the crank.. this is an 1100g motor that was recently rebuilt (not by me) and was running in an outfit. I had just crossed Australia and was heading home (10,000km in 10 days) but after only 6000kms it started making noise.

Nasty stuff. That pin has two old cracks, one at 12 o'clock the other at 6 o'clock. The one at the bottom has been there for a long time before she broke. There was only 40% of metal holding it together before it let go.
I guess that it would have been hammered at high rpm's continuously when fitted to the outfit. Had it been drastically over bored?

[slob]

I guess that it would have been hammered at high rpm's continuously when fitted to the outfit. Had it been drastically over bored?

I was running it at about 6500 rpm continuously for 2 hours, four times a day for about 6 days before she let go. The cylinders were standard size. The rest of the motor is fine.

QUESTION:

Should I replace the crank with the one from a worn out motor, or re use the top end on another motor?

[49er]

I was running it at about 6500 rpm continuously for 2 hours, four times a day for about 6 days before she let go. The cylinders were standard size. The rest of the motor is fine.

QUESTION:

Should I replace the crank with the one from a worn out motor, or re use the top end on another motor?

I'm obviously confusing outfits. I thought you were referring to a speedway outfit (sidecar) running at high rpms each race. I'm not sure what outfit you were referring to.
You should try and source a low to moderate kms replacement motor. A worn out motor is likely to have worn out/almost worn out crank and bearings.

[slob]

It's a sidecar outfit I use on long trips here's a pic in central Australia. I have a tired old motor in the outfit at present I'll take the crank out of that and put it in the other motor then.

[49er]

It's a sidecar outfit I use on long trips here's a pic in central Australia. I have a tired old motor in the outfit at present I'll take the crank out of that and put it in the other motor then.

That outfits been around alright. You weren't racing the Ghan when that crank let go, where you?
My wife just quipped, "that sidecar's fitted with a solar panel".
Good luck with the rebuild.

[slob]

Racing the Gahn, funny you should mention that. I ran it up the Oodnadatta track at Christmas along the old ghan site, after I changed motors from the Gascoyne junction trip. Now that was a rough trip one day I had 9 punctures. Yes the solar panel was supposed to run a fridge but my understanding of solar was limited and I didn't have enough amps. It did charge the mobile phone though, it's gone now.

[Killer2600]

It is bullet proof, it'll stop a bullet won't it :-D

[49er]

Geez, 9 punctures in one day!! Would make ya wanna stop off at the Birdsville Races for a week.
Do you carry spare tyres in the outfit? I guess the puncture repairs are done in record time these days!
How big is the oil cooler? Its had to tell from the pics. You need plenty of capacity for that heat.
Your sidecar probably needs to be fully covered in solar panels to power the beer frige!!

[slob]

yeah thinking of a bigger oil cooler and maybe a reservoir somewhere as well. I have a rubber mallet and tyre levers in the sidecar and do my punctures the old fashion way with a patch on tubes. Have a small compressor now too after busting the foot pump. It seems the Chinese dont make pumps very well.

[49er]

yeah thinking of a bigger oil cooler and maybe a reservoir somewhere as well. I have a rubber mallet and tyre levers in the sidecar and do my punctures the old fashion way with a patch on tubes. Have a small compressor now too after busting the foot pump. It seems the Chinese dont make pumps very well.

Have you ever tried fitting one of those spark plug adaptors to inflate your tyres with the engine running?