Originally Posted by
infernotb
Just my 2 cents on this and i may be way off the mark but i tried tuning to this method and it just did not work. Trying to get it to shut off at the 7 sec mark made it way to rich on the bottom end, it would not idle properly and i gave up and went back to the old method of tuning the low to give good takeoff and performance then fine tune the top end as per Grizzs advice. The HSN doesnt need much tweaking from flush.
I dont know who else has tried this 7/8 sec magic number tune method and would be keen to hear who has, like i say i may be missing something but that was my experience.....
Hmm - it's hard to argue with Massive's wisdom. He is the GO Guru !!
I must confess I have always used the 4 - 5 sec pinch rule for the LSN. Pinch off the line and the motor should rev up only slightly (indicating a correct idle gap), then should die between 4 and 5 seconds. This has worked in the past on the Gen 5 motors I have run, but it may be a little different with the new GX and MG carbs with the new HSN needle etc.
Be aware that a rich bottom end will also give a high rev when you pinch the fuel line off, as you are leaning a motor that is too rich, so it will speed up before it dies. Conversely if your bottom end is too lean the motor will simply stop fairly quickly with no rise in revs at all.
Hi Jeff - My old Gen 4 was a bit like that. The needle settings were way different to the Gen 5 and younger motors.
As long as it's haulin butt and you have smoke right through the rev range it must be good.