Hello Louie!
On 19 May 97, Louie Gonsalves wrote to All:
 LG> Problem is, it won't idle worth a spit.  It's got the original OS 4BK
 LG> carb, ya know, the big-bore carb like the more modern SF and FX series.
The big bore kit definitely isn't helping.  I have an ASP.61 with a similar 
problem.  It's a tradeoff... a big bore will allow very high RPM, but kills 
the bottom end, same as with automobiles or bikes.
 LG> I've tried setting the low-speed needle, but still won't really idle as
 LG> reliably as I need it to be...
I'd replace the entire needle assembly (if you can find it).
 LG> but it won't idle!  I've been told ringed engines don't make compression
 LG> till they're running -- sounds fishy, I used to have a Honda 80cc four
 LG> stroker dirtbike, and it had PLENTY compression =-)
I agree... my OS 1.08 and YS.61 have a LOT of compression.  If you have ring 
or sleeve wear, it will kill compression at idle while allowing the engine to 
really open up at the top end due to the reduced friction.
 LG> SO...  what can I do?  Try 15% nitro?  I usually run 5%.
Definitely.  Even on good engines, I never had good luck with 5% and 10% 
fuels. Expect some drop in top end RPM though, as the 15% will cause the 
engine to run hotter, causing it to expand more and run a bit tighter.
 LG> New carb?  I
 LG> can't find it listed.  The SF uses a 4D, I wonder if it'll fit.
You should be able to use any carb with the same base diameter and mounting 
method.  Pull the old one off and take it with you to check.
C-ya! Rich
--- GoldED 2.40
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