Author Topic: shut down with PG  (Read 4398 times)

Offline noslin

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shut down with PG
« on: June 04, 2017, 08:08:46 PM »
ive only raced manual trans, first time with automatic.

so, if you want to get plug reading and kill the motor as you go through the traps.  what do you do with the trans. just leave in drive or do you put in neutral or ? 

ty
dean

Offline bikeguy307

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Re: shut down with PG
« Reply #1 on: June 05, 2017, 05:42:14 AM »
Common practice it to put it in neutral at the finish line. This gives a clean release of the high cluch. Killing the motor in gear leaves you with a release caused by the pressure loss as the engine shuts down, this causes a drag on release. Not sure hoe many times this would have to be done to cause clutch damage, but better safe than sorry, put it in neutral first.

dreracecar

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Re: shut down with PG
« Reply #2 on: June 05, 2017, 08:13:57 AM »
If you are running Alc, you are not going to get much of a reading as you do gas. Any reading I do(shut-off does not matter) is by counting the number of discolored threads on the NGK plug
2-3 threads and you are safe with 3 being the best
4 threads and you are pretty close to the limit before you hurt somthing

Offline PSweeney

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Re: shut down with PG
« Reply #3 on: June 06, 2017, 04:52:01 AM »
If the motors not running, you have no trans pump pressure.  Even if you shift into neutral, you still have components driven by the output shaft rotating at speed with no pressurised lubrication.  It might not kill it, but it won't be good for it.

Offline bikeguy307

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Re: shut down with PG
« Reply #4 on: June 06, 2017, 05:27:04 AM »
Agreed, spinning parts and no pump pressure is never good. How ever for a plug check it's a trade off that needs done. Definitely not something that sould be done often.

Offline dusterdave173

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Re: shut down with PG
« Reply #5 on: June 06, 2017, 06:26:09 AM »
with alky there is almost nothing you can tell from plugs except what has already been mentioned on thread reading--I like to see where the line is on the ground strap which helps with timing--I always get best performance when that line is in the bend of the ground strap--checking an alky plug for mixture is just not going to work for average guy--
Threads are best indication IMO    also check inside header pipe--sticky is good
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