Needle help?

[norwegian]

The best yamaha mechanic in my county and the yamaha book do not agree which way you count the grooves on the needles. He states that from this pic which is attached that 2,5 by the pic is actually 3,5. One other thing is that he says that the nearer the "fat end" of the needle, the richer?
But surely a yamaha update book can't be wrong?
Who's right?

 

[TJ500]

the diagram you show and any that we've ever looked at in any Yamaha manuals, are the same....

also

when you move closer to the fat end of the needle with the clip (strictly clip position),,,, it is not richer... It is LEANER...

those kind of misunderstandings can be dangerous...

appears he is counting wrong.. BE CAREFUL


tj

 

[BigMac]

the diagram you show and any that we've ever looked at in any Yamaha manuals, are the same....

also

when you move closer to the fat end of the needle with the clip (strictly clip position),,,, it is not richer... It is LEANER...

those kind of misunderstandings can be dangerous...

appears he is counting wrong.. BE CAREFUL

Every carb with a needle I've ever used suggests that raising the needle (clips and shims moved down toward the pointy end) richens up the midrange.

That diagram has been in every Yamaha service manual I've ever seen for years in carbs that use Mikuni carbs. If it were wrong, surely someone would have mentioned it by now...

 

[vipertripplexxx]

Got news for ya

The best yamaha mechanic in my county

He's not the best mechanic in the county, unless your for zimbabwe!
Moving the clip tward the pointed end (down), will raise the needle higher, letting more fuel pass through the needle jet, with less throttle opening(richer)!
Wrong on both counts!

 

[woolyviper]

I agree - moving the clip and spacers closer to the tip pulls the tip out of the needle jet sooner creating a rich condition.

 

[norwegian]

Thanks for the replies guys now I know what to do with them..