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Author Topic: IMS tuning  (Read 506 times)

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Offline 550Resto

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IMS tuning
« on: August 06, 2016, 05:44:07 AM »
Hello all, I had a question regarding my 78 550 PDC carbs. I've seen talk of adjusting the IMS screws at idle to achieve the highest idle and was hoping someone could explain this procedure and why it's done if the stock setting is 1.5 turns out? TIA
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Offline FunJimmy

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Re: IMS tuning
« Reply #1 on: August 06, 2016, 07:16:51 AM »
While the manual may state that stock tuning is 1.5 turns out every bike is different. Especially a 35+ year old bike. Wear and tear, state of tune, condition of carbs all have an effect.
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Offline flybox1

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Re: IMS tuning
« Reply #2 on: August 06, 2016, 08:03:05 AM »
Adjust your IMS with the goal of acheiving correct plug color, not idle.
Everyones ears hears differently, and you cant 'hear' proper air/mixture.  Going by idle is inacurate.
do an idle plug chop with new plugs, and adjust each IMS as needed based on plug color.
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'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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