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B needles VS stock needles and some questions~


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ZeroKenshin
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B needles VS stock needles and some questions~

Fri Nov 06, 2009 4:35 pm » Post: #1 » Download Post

Im sure there's a topic over this before but i would really like to know more about it...

As B needles are adjustable.. they are more easily tuned than Stock needles.. but whats the difference between them as they are extremely equivalent? regardless the adjustment that is, is it possible to tune the Carbs to kick as much power as nearly to the B needles? if so what are the things i can do? so far what ive came to know about is to modify the airbox lid , changing jets and slight adjustment of the air screws...

oh yea and im caught up with a problem... wonder if anyones' ever encountered with similar problem of mine..

My engine vibrates slightly harder when it reaches between 7k rpm to 9k rpm..
and my speedo on my pgm4 will go crazy.. e.g: random speeds keeps changing... 156, 180, 133, basically jumping around.. but its working fine during revs before 7k and after 9k...

activities before this occurred ,,
had changed plugs.. NGK 9" plugs
changed my MJs to 150..
to what im expecting .. it might be my ignition cables..

thanks for reading up guys~ and really appreciate your feed backs and answers =) Cool
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fontyyy

 
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Re: B needles VS stock needles and some questions~

Fri Nov 06, 2009 11:22 pm » Post: #2 » Download Post

ZeroKenshin wrote:
and my speedo on my pgm4 will go crazy.. e.g: random speeds keeps changing... 156, 180, 133, basically jumping around..


I've seen that, no idea what it was but the PGM packed up about half an hour later Shocked

Sorry I can't help more.
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ZeroKenshin
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Sat Nov 07, 2009 2:06 am » Post: #3 » Download Post

thanks for the reply fontyyy~ but what do you mean by packed up about half an hour later?
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StephenRC45
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Sat Nov 07, 2009 10:46 am » Post: #4 » Download Post

He means the PGM failed shortly after.
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Andy
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Sat Nov 07, 2009 2:50 pm » Post: #5 » Download Post

You've got two questions here really:

1. Carb tuning with HRC "b" needles (which is why I've moved the topic).
2. Poor running that's not necessarily associated with the needles.

To answer question one, HRC needles won't give you more power over stock needles. What they will do is allow you to fine tune the fuelling at part throttle and as you wind the throttle on. You can (usually) make the engine run smother with adjustable needles... but only if other modifications have been made.


As B needles are adjustable.. they are more easily tuned than Stock needles.. but whats the difference between them as they are extremely equivalent?

This is why we generally tend to use "b" needles. Honda, unsurprisingly, got it very right with the OEM needle profile, and it works in virtually every climate. Yes it will be a little too rich in certain climates, but it will never be too lean, and the profile "just works" on a standard bike!

When you start to change things and develop though, you generally find the fuelling can go lean or rich at a certain throttle opening. The HRC "b" needle still usually tends to be the best needle because as I say, the OEM needle is good in all conditions, but being able to raise or lower it simply means you can adjust out the particular trouble spot on the throttle.


My engine vibrates slightly harder when it reaches between 7k rpm to 9k rpm..
and my speedo on my pgm4 will go crazy.. e.g: random speeds keeps changing... 156, 180, 133, basically jumping around.. but its working fine during revs before 7k and after 9k...

This needs to be asked again in the public forum. Make mention of the adjustable needle change too, but please keep any HRC-specific questions to this area.
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ZeroKenshin
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Sat Nov 07, 2009 6:58 pm » Post: #6 » Download Post

Thanks alot Andy, thats certainly some useful information! oh yeah , ive rectified the problem.. found out that i have a faulty pulse generator, had it changed and a-okay~ problem done!, ive done modifications to my air box lid and upped my MJs to 160 and 158 , AJ to 40, and it runs like a healthy horse!
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