I have a strange problem that I’m unable to resolve and I’m open to any sensible suggestions from those in the know who think they may know what’s causing my problem.
My engine: a 2004 Softail TC88B modified to a 103 ci, with head work and gear driven cams, and using ThunderMax Autotune. Up until a couple of weeks ago everything was working excellent, perfect idle, a smooth running engine and with plenty of power...and it still is except for the following.
My problem: If I’m to rev the engine out fast and hard, i.e. 75% - 100% throttle to high RPM (above 4,000) it seems like an electrical fault is activated. Though the engine will continue to run nicely if the RPM is kept above 2,000, but the decell feels dead, it's as if there’s no spark or no fuel on decell, it feels as if a kill switch has been activated. However, if the RPM is kept up above 2,000 everything still works fine, just the decal feeling dead and if I allow the RPM to drop below 2,000, slow down, i.e. to stop at traffic lights the engine dies, it stops dead, no sound, no complaints, no miss firing, no popping or back firing...it just dies in the (EDIT) , dead as a door nail as if a kill switch has been activated....although all of my electrics still work fine, lights, dash, etc, everything is working normal, just there's no spark or fuel to fire the engine or to keep the engine running if below 2,000 RPM.
The engine will not start again unless I switch the ignition off and back on again...then all is as normal and engine runs perfect again as though nothing ever happened. No fault codes, nothing at all, just the announce of having to stop, switch off and on and restart.
However: If I ride the bike smoothly, i.e. slow easy throttling it’ll rev out to red-line without an issue what so ever, it'll run all day without a problem at all, with plenty of power and everything smooth as silk....Twist the throttle hard and fast at anytime and the fault is activated again, requiring me to stop and switch the ignition off and back on again.
My thoughts:
ThunderMax? How and why everything is working fine, it’s only if I rev hard & fast.
Fuel pump? The fault would be happening all the time.
Fuel Filter? Same as above
Vapour lock? It would be happening if rev’d fast or slow
Plugs? They’re excellent, new 2 months ago and inspection looks normal
Poor fuel? I’ve been through 3 tanks from 3 different suppliers and it’s still happening
Coil? If it fails at hard full throttle it would also fail if rev’d out slow and easy
TSM-TSS (accelerometer)? Could it be failing when under fast acceleration?
Water in Electrics? maybe the TSM acceleromter is triping the kill switch, but why does it still run if rev’s are kept up, the kill switch kills the engine, no power at all, it wouldn't continue to run if revs are kept up?
A lose wire somewhere? why only under hard fast throttling, it would also be happening if on a bumpy road, but it deosn't.
Please read this...
My engine: a 2004 Softail TC88B modified to a 103 ci, with head work and gear driven cams, and using ThunderMax Autotune. Up until a couple of weeks ago everything was working excellent, perfect idle, a smooth running engine and with plenty of power...and it still is except for the following.
My problem: If I’m to rev the engine out fast and hard, i.e. 75% - 100% throttle to high RPM (above 4,000) it seems like an electrical fault is activated. Though the engine will continue to run nicely if the RPM is kept above 2,000, but the decell feels dead, it's as if there’s no spark or no fuel on decell, it feels as if a kill switch has been activated. However, if the RPM is kept up above 2,000 everything still works fine, just the decal feeling dead and if I allow the RPM to drop below 2,000, slow down, i.e. to stop at traffic lights the engine dies, it stops dead, no sound, no complaints, no miss firing, no popping or back firing...it just dies in the (EDIT) , dead as a door nail as if a kill switch has been activated....although all of my electrics still work fine, lights, dash, etc, everything is working normal, just there's no spark or fuel to fire the engine or to keep the engine running if below 2,000 RPM.
The engine will not start again unless I switch the ignition off and back on again...then all is as normal and engine runs perfect again as though nothing ever happened. No fault codes, nothing at all, just the announce of having to stop, switch off and on and restart.
However: If I ride the bike smoothly, i.e. slow easy throttling it’ll rev out to red-line without an issue what so ever, it'll run all day without a problem at all, with plenty of power and everything smooth as silk....Twist the throttle hard and fast at anytime and the fault is activated again, requiring me to stop and switch the ignition off and back on again.
My thoughts:
ThunderMax? How and why everything is working fine, it’s only if I rev hard & fast.
Fuel pump? The fault would be happening all the time.
Fuel Filter? Same as above
Vapour lock? It would be happening if rev’d fast or slow
Plugs? They’re excellent, new 2 months ago and inspection looks normal
Poor fuel? I’ve been through 3 tanks from 3 different suppliers and it’s still happening
Coil? If it fails at hard full throttle it would also fail if rev’d out slow and easy
TSM-TSS (accelerometer)? Could it be failing when under fast acceleration?
Water in Electrics? maybe the TSM acceleromter is triping the kill switch, but why does it still run if rev’s are kept up, the kill switch kills the engine, no power at all, it wouldn't continue to run if revs are kept up?
A lose wire somewhere? why only under hard fast throttling, it would also be happening if on a bumpy road, but it deosn't.
Please read this...
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