RunRyder RC
WATCH
 1 page 886 views POST REPLY
HomeRC & Power✈️Aircraft🚁HelicopterEngines Plugs Mufflers Fuel › YS91ST Needle Settings?
01-27-2007 08:55 PM  12 years ago
Topic Vote0Post 1
Dr.Don

rrVeteran

Cedar Park, TX -- USA

MyPosts All Forum Topic
YS91ST Needle Settings?
YS91ST with about 2 gallons through it before I got it. Running MPII, 8.27 gears. Having some issues getting the needles set for a good transition from idle through the mid-range. Give me some idea where you guys' needles are. I am in the range in the manual, but not sure which way to go to smooth it out.

Thanks
Dr.Don
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
01-28-2007 01:37 AM  12 years ago
ErichF (RIP)

rrElite Veteran

Sutton, NH

MyPosts All Forum Topic
Lose the Muscle Pipe, it's inherently unstable with that muffler, for some reason. Get a Hatori or equivalent clone. I got the Century Quiet Tune 90 muffler (made by Hatori), and it's just great. Not as quiet as say a Hatori SB 17 or so, but runs very nice.

I'm on the lean side of the idle needle range, and the rich side of the hover needle, and 3/4 on the high needle.

That's with OS #8, and Cool Power Performance heli 20%, 7.92 ratio, 1900 and 1500 rpm.

Erich
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
01-28-2007 04:34 PM  12 years ago
Dr.Ben

rrMaster

Richmond, VA, USA

MyPosts All Forum Topic
Poor transition can often be caused by either too rich an idle or hover mixture OR a combo of both. If the engine doesn't repond to gently leaning of these mixtures, try another muffler. If the problem persists, replace the carb's barrel. Yes, the barrel. You'll sometimes see one mismachined.

RE the hover needle setting, keep leaning it in until the engine cackles, then richen it back up 4-6 clicks. You must have the midrange tuned correctly or the engine simply won't run worth a darn. Erich is right about the idle mixture. Keep it as lean as reasonable without having the engine hang on the pipe in an auto or other chatter/cackle at idle.

Ben Minor
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
01-28-2007 05:18 PM  12 years ago
jsenicka

rrProfessor

Eagle River, WI

MyPosts All Forum Topic
I am at about 1.25 + a click on hover, and between 5/8 and 3/4 on high speed. Idle is about 1/4 turn in from flush with the housing. Still a bit rich. Agree on needing to get the midrange right!Jim Senicka
Team Manager, GrandRC Flight Team
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
01-30-2007 05:27 PM  12 years ago
Dr.Don

rrVeteran

Cedar Park, TX -- USA

MyPosts All Forum Topic
Thanks for the help guys. I am going to invest some more time fiddling before I give up on the MPII. Will concentrate on getting the hover needle right, then move back and tweak the idle needle. No time to get on it until the weekend...too dark when I get home now.Dr.Don
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
02-03-2007 01:57 PM  12 years ago
jsenicka

rrProfessor

Eagle River, WI

MyPosts All Forum Topic
I would look at an MP5 if you want to stay with the MP.
YS on a Hatori is a thing of beauty. YS on an MP2 will always be tweaky
Jim Senicka
Team Manager, GrandRC Flight Team
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 1 page 886 views POST REPLY
HomeRC & Power✈️Aircraft🚁HelicopterEngines Plugs Mufflers Fuel › YS91ST Needle Settings?
 Print TOPIC  Make Suggestion 

 1  Topic Subscribe

Monday, November 18 - 1:04 am - Copyright © 2000-2019 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online