Badgasser bends a crank!!

[Gaba]

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Yep . Whiplash gasser made so much insane power on the tunes pipe! My crank went out of round!!!!!! Can you believe that?

Took this engine out as e clutch was dragging all of a sudden and the engine started making noises.. No problem in the piston or head as I can tell!! But man!!!

The bird had more power than I could use! I wish someone would have taken a video. The engine sounded amazing and wow with 2250 headspeed and tons of torque, I was just so happy... Until I got into tuning it a bit and it was a cold day. My spark plug was still wet with fuel and oil.. So that means rich. I went 1/16th turn in , and engine was perfect chocolate brown spark plug.. Just at the edge of dry not yet... Just yummy. Lol ... But yeah the crank couldn't hold all that power !!!

[danhampson]

That's insane Gaba. So what's next, is there a crank upgrade? ☺

[KevG]

Wow that's just nuts, Gaba the ever impressive,

[Gaba]

It is awesome to think about .. But .. No crank upgrade. Because this engine is ported and balanced by a modifier.. Crank was modified and weighed statically and dynamically to match the exact weight needed so there is no vibration. Also the motor was stroked by 1mm to increase displacement from 26cc to 27.5cc .. Obviously I didn't do all that. It was TRM power . That also means crank or anything in the motor is not a drop fix . It will involve me sending the motor to the modifier. He will tear into it. Assess the real damage , and then build the crank for me , or build a new motor ... And that just sounds like $€£¥$ flying away... lol

So ... We will see I have contacted the modifier and waiting to hear back

[Graham Lawrie]

Gaba, not sure if that amount would cause any problem as the shaft is tapered? I take it is going on to a woodruff key? For me you would need to take a measurement at the largest section of shaft nearest the bearing as well to see what the deflection on the DTI guage would be over the distance of the shaft from bearing end to thread end.

If there is no vibration i dont see it being an issue? How is the other end? the female section it fits in to? You would need to see if there is wear on it. My money would be on there being more wear on it rather than the shaft?

[murankar]

More power Scotti. I'm given 'er all she's got capt'n.

DAAAAAAAAAAAAAAAAMN, you got knocked the freak out!!!!!!

[Gaba]

Gaba, not sure if that amount would cause any problem as the shaft is tapered? I take it is going on to a woodruff key? For me you would need to take a measurement at the largest section of shaft nearest the bearing as well to see what the deflection on the DTI guage would be over the distance of the shaft from bearing end to thread end.

If there is no vibration i dont see it being an issue? How is the other end? the female section it fits in to? You would need to see if there is wear on it. My money would be on there being more wear on it rather than the shaft?

Well here was the issue. The magneto disc was rubbing up on the pick up now. Wasn't before. The starter shaft was rubbing up on he one way bearing , that made the clutch grab at the high point.

And when rotating the engine in the frame, the bell was moving side to side . All that made for a clunky noise and vibration in the air. Hence it was put on a test bench. No hard landing no crashes. Just pure pipe power!!!


The acceptable tolerance there is .005-.01" . The issue continued through the whole crankshaft top to bottom. I wish it didn't. But I am going to call AL from TRM power today. He has agreed already to get into the engine to fix it. But I will now see what cost and more techinal details

[Gaba]

http://www.youtube.com/watch?v=phulD6neFRc

Enjoy

Slow motion cause my hand kept moving around. Look between the crank and the brads collet/ bearing

[Gaba]

Ok update to this .

Metal epoxy used to shape ports came off and caused havoc inside the engine. Beatings were shot and crank was twisted . It must have locked up the motor for a split second , and the momentum pulled the motor out of it killing it while doing it

[murankar]

Replacement?

[Gaba]

Replacement?

Yeah TRM Power Al , opened the engine completely and saw the havoc. and reported back. He wasnt the one who modified it to start with, it was someone offbrand. He didnt prep the cylinder walls so the high stress environment, the epoxy let go

short answer.. YES! lol almost a complete replacement. I am buying his TRMpower VX300TT now!! its the biggest highest power helicopter gas engine in the market 29.5cc of displacement, and just GOBS of power. My old one was close to TRM's 275 .

All I gotta say is OUCH!! offbrand crap bites me in the butt yet again! lol

[Graham Lawrie]

Is it me or is the seal moving? It looks distorted at the start?

[murankar]

At least its not a grassy field, lol.