20 replies to this topic

[cal844]

I'd love to see one being modified as I think I need to make a custom needle :)

[KernowCooper]

I did one for mine with a CO meter onboard and tweaked mine over a week, well worth spending the time to get it right

[__Alex__]

AC,

 

Could you help me understand why I would need a custom needle? There are hundreds of stage 1 HS4 998cc running either AAU or AAA, what's so special about my engine? Wear? 

[ACDodd]

95% of 'those' engines don't run right either, its just there owners don't realise it. AAA engines run bore washingly rich and the aau engine run flat spot lean. There are of course exceptions, but most I see fall into the above!

AC

Edited by ACDodd, 07 August 2015 - 04:50 PM.

[carbon]

Alex, to see the difference between AAU and AAA needles use this link : http://www.mintylamb.co.uk/suneedle/

 

Would recommend you getting a new red spring for the dashpot. I've had similar issues with weak spot on twin HS2s and keeping the same needle but going from blue to red springs sorted this. In your case yellow spring would be way too heavy, that's why I would suggest a new red spring - the one I got about year back from Mnispares was usefully stronger and managed to cure a flat spot on my 998.

 

And if you really want to try a different needle then the ADL may richen up the mid-range very slightly compared to AAU

[__Alex__]

All right, thanks for all your answers, I'll look into it.