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Williep13
Posted on Sunday, October 03, 2010 - 09:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I have heard this a few times recently what exactly is Limp Mode and what does it do?
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Froggy
Posted on Monday, October 04, 2010 - 01:59 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

You mean skip spark? On fuel injected Buells, if the motor starts to overheat it will intentionally miss-fire the rear cylinder to cool off the motor. The check engine light will flash while this is happening.


I am unaware if the carbureted bikes have this feature or not.
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Natexlh1000
Posted on Monday, October 04, 2010 - 07:27 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I don't think the carbed bikes are "aware" of their own temperature.

I think the only sensor that relates to the ignition is the VOES.
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Xl1200r
Posted on Monday, October 04, 2010 - 02:31 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"limp mode" and "skip spark" aren't necesarily the same thing. Skip spark was explained, but limp mode is essentially what the engine is running in nearly any time the CEL is on. Basically, if the CEL is on, the engine knows that there's either a mechanical problem that evidenced by an out of spec reding from a sensor, or there's a sensor issue giving unexpted values. In either case, the ECM reverts to a "safe mode" where the sensors are not used but it uses paramters that will not harm the engine. Generally results in poor gas mileage and poor performance.
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Williep13
Posted on Monday, October 04, 2010 - 02:54 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Would the bike running fine and not allowing it to go over 3500 RPM's be a symptom? It would show up on ECM Spy wouldn't it?
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Hootowl
Posted on Monday, October 04, 2010 - 04:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If you are indeed in limp mode, you should see a sensor error code.
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Terrycoxusa
Posted on Monday, October 04, 2010 - 08:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If the 'limp home' mode fails, the rider defaults to the 'walk home' mode.
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Hootowl
Posted on Tuesday, October 05, 2010 - 12:12 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Or the "push bike home" mode.
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