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Discussion Starter #1
I've got a question after chatting with Mike briefly after my dyno run. He said that I can get rid of my flat spot by going 2 clips up on the mains. He said it's a fairly straight forward cure for the power dip symptoms that my bike has.

I don't know much about carburation tuning so in my quest for knowledge: Does anybody know what this means? What will it do for my fuel delivery?

Also, what does pinging sound like on a bike? I hear this "zing" sound when I hit 7-8k rpm concidentally where my power dips. It sounds like a really high pitched rattling or drilling. I'm hoping that my bike doesn't ping on 92 octane gas...
 
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2 clips up means. the clip on your needles should be moved 2 slots up.are your needles stock or aftermarket.is it a rattle like something slapping against the inside of the engine.does it happen just at that rpm. how's your cam chain tensioner?
 
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if it is your main jets then 2 sizes up on your main jets carbs are a tricky subject.
 

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Discussion Starter #4
I've got the full Muzzy with a factory jet kit. The sound only happens for a thousand rpms. It's hard to describe other than a dentist drill touching a tooth for a second then it's gone. No slapping sounds here.

And I'm not sure how to diagnose my camchain tensioner. BK opened it up a month ago and I'm assuming that they screwed everything back togther all tight.
 
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cam chain tensioners when loose making a very distinctive metallic"clicking" sound at certain rpm's ....usually around 5-6k...doesnt sound like your problem
 

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Yeah, I've ridden Sewman's bike...and from the way that you guys are describing it, I don't think it's the cam chain tensionor. It almost sounds like a whining, whizzing sound...like the dentist's drill. Sewman, take it back to BK next week. I'm heading down there to pick up my bike on Wednesday (hopefully!) just meet me down there. We'll go for a ride afterwards if it's nice!
 
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ride it over 8grand AT ALL TIME and your problem is solved!:evilgrin

tc
ps and it's free too...
 

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clip's and main's are two totally diffrent things?

to raise your needles(mid range power) you take the needle out and move the needle clip up on the needle enabling the needle to drop a fraction to reduce the flow of gas.

to go up two sizes on the main's is to take out the main jet you have in there right now,and replace it with a jet 2 sizes bigger, to allow for more gas delivery?

you seem to be asking for more of less here?
 

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Lugan said:
Sewman, nice numbers! If you have time, check the following link for some general info on carbs, and needle adjustment; it's mainly focused on the vmax, but the general idea carries over. http://www.geocities.com/MotorCity/Speedway/2476/basics.htm
If you're heading to RMS (i think) for another dyno pull next w/e, let me know.
Hey thanks for that link, cleared up needles a bit for me. I kinda knew how carbs worked in general but didn't understand the needle/jet mechanism.. just that the jets were there.

So non constant velocity carbs would probably be the ones w/o needles right? Since the air flow itself could regulate the fuel flow?

I'll finish reading that article later :)
 
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