Winner Of The Race Engine Challenge

General engine tech -- Drag Racing to Circle Track

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MadBill
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Re: Winner Of The Race Engine Challenge

Post by MadBill » Wed Nov 07, 2018 2:47 pm

nitro2 wrote:
Wed Nov 07, 2018 11:14 am
...Also in some other types of racing, such as 2 stroke marine racing, there can be weird on/off throttle scenarios that cause engine failure in a race, but there is seemingly no way to duplicate it on the dyno (the engine on/off throttle scenario can be duplicated, but not the failure).
One could see how this might happen with pre-mix: closed throttle = no air = no fuel = no lube... :-k Not with oil injection of course.
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Re: Winner Of The Race Engine Challenge

Post by nitro2 » Wed Nov 07, 2018 11:34 pm

MadBill wrote:
Wed Nov 07, 2018 2:47 pm
nitro2 wrote:
Wed Nov 07, 2018 11:14 am
...Also in some other types of racing, such as 2 stroke marine racing, there can be weird on/off throttle scenarios that cause engine failure in a race, but there is seemingly no way to duplicate it on the dyno (the engine on/off throttle scenario can be duplicated, but not the failure).
One could see how this might happen with pre-mix: closed throttle = no air = no fuel = no lube... :-k Not with oil injection of course.
Not that kind of failure.

Detonation failure. Closing/closed throttle 2 stroke detonation. This type of detonation is common, even on mundane stuff, but on higher powered applications is more intense. "Detonation" is a bit generic, can be HCCI. Generally very brief, but it doesn't take much to cause damage on a 2 stroke. Opening the throttle at just the wrong time after closing it can be worse yet.
TFX Engine Technology Inc.
High Speed Combustion/Intake/Exhaust Pressure Tuning Equipment
www.tfxengine.com
1-800-479-5571

cjperformance
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Re: Winner Of The Race Engine Challenge

Post by cjperformance » Thu Nov 08, 2018 5:22 am

nitro2 wrote:
Wed Nov 07, 2018 11:34 pm
MadBill wrote:
Wed Nov 07, 2018 2:47 pm
nitro2 wrote:
Wed Nov 07, 2018 11:14 am
...Also in some other types of racing, such as 2 stroke marine racing, there can be weird on/off throttle scenarios that cause engine failure in a race, but there is seemingly no way to duplicate it on the dyno (the engine on/off throttle scenario can be duplicated, but not the failure).
One could see how this might happen with pre-mix: closed throttle = no air = no fuel = no lube... :-k Not with oil injection of course.
Not that kind of failure.

Detonation failure. Closing/closed throttle 2 stroke detonation. This type of detonation is common, even on mundane stuff, but on higher powered applications is more intense. "Detonation" is a bit generic, can be HCCI. Generally very brief, but it doesn't take much to cause damage on a 2 stroke. Opening the throttle at just the wrong time after closing it can be worse yet.
I have had quite a few 2 stroke bikes but am not a 2 stroke tuning specialist. I'd like to hear some more explanation/thoughts on this as I have experienced some odd 2 stroke tune/plug issues particularly with an ex race Yamaha RZ500 V4 2 stroke that i had bought years back and never thought about since till i just read this.
Craig.

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Re: Winner Of The Race Engine Challenge

Post by nitro2 » Sat Nov 10, 2018 1:23 pm

Well it's interesting to discuss, but getting pretty far off topic here, so probably something best left for another day, another thread, unless REC starts running 2 strokes #-o
TFX Engine Technology Inc.
High Speed Combustion/Intake/Exhaust Pressure Tuning Equipment
www.tfxengine.com
1-800-479-5571

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