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Discussion Starter #1
I have an 05 Suzuki m50 fairly new bike 4500k miles I am having a issue at cold start it wont keep itself running I can feather it an keep it running but as soon as I let off the throttle it dies I tryed adjusting the idle speed knob but that only increased rpms while I ran the throttle to keep it running there is another smaller screw beside the idle adj kno that's moves slightly forward when I hold it up the bike stays running what is this screw an of I adjust it forward will it cause problems
 

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That would probably be either a mixture screw or, more likely, an air screw. You need to find out which it is as they will do opposite things.....an air screw turned in will make the fuel/air ratio richer. Conversly a mixture screw turned in will make the ratio leaner. If you turn it make sure you know which way you did and by how much.

With these settings I tend to turn them fully in untill slight resistance is felt counting how many turns that takes. This gives you the basic setting. Do not turn the screw in too hard or you may damage the needle tip and/or the jet it meters.

A small dab of paint or similar where the head slot is before turning it will help in returning it to its original setting.


I just reread your post and wonder if I am correct....you say this screw moves slightly when you hold it up....not too sure what you mean and any screw that moves is probably attached to some of the throttle linkage. A picture will help with any assistance given.

Good luck
 

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Discussion Starter #3
The screw itself isnt loose it's the mechanism its attached to moves forward slightly when its held inward the bike will stay running
39695
 

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Discussion Starter #5
It is apart of the throttle linkage just unsure of what it's for an if I adjust forward will it hurt anything like I say the bike runs on it's own when this screw linkage is moved forward pushing that lever so I'm wondering if I screw it in enough to push the lever up if that may be my problem
 

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That is very likely to be a fast idle screw and it only comes into play when the choke/enricher is activated. It is fine to adjust it so the cold start rpms are higher. It should drop back down to normal rpms once the choke/enricher lever is pushed closed.
 

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A throttle lock system wont fix the original problem though.
 

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If I remember correctly, this is a fuel injected bike, so I would check the fuel filter first if it has one. If thats not it, then check the fuel pump, as these two things are probably the most likely.
 

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If I remember correctly, this is a fuel injected bike, so I would check the fuel filter first if it has one. If thats not it, then check the fuel pump, as these two things are probably the most likely.
The discussion so far sounds like it has carbs.
If so, proper use of the CHOKE is very important.
 

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Suzuki changed from carbs to FI in 05 and the name was changed from the VZ800 Marauder to the M50.
 

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Suzuki changed from carbs to FI in 05 and the name was changed from the VZ800 Marauder to the M50.
Well then the first recommendation would be a healthy dose of injector cleaner......like B12 or Techron.
That is IF the intake and exhaust are still stock.

Then I would suspect that the coolant temp sensor is going bad and not reporting that the engine is COLD to enrich the mixture. That can happen if the coolant is way low too.
 
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