R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro Off-Road

Thread Tools Search this Thread
Old 03-22-2009, 08:09 AM   #1
Tech Initiate
Join Date: Jan 2009
Posts: 47
Default 4 Cycling-2 Stroke

When 4 cycling occurs in a 2-stroke nitro engine, how should you systematically determine what is causing the problem?

I had this happen yesterday, and we eventually corrected the problem, but several of us had trouble determining what to adjust.

It would occur when we came off of full throttle. I thought it was the low speed needle, the others thought that it was the high speed setting.

Any help would be appreciated.
tk1931 is offline   Reply With Quote
Old 03-22-2009, 08:32 AM   #2
Tech Champion
Davidka's Avatar
Join Date: Oct 2004
Posts: 9,995
Trader Rating: 77 (100%+)

4-stroking is caused by a too-rich setting dumping more fuel into the engine than it can burn so it sputters. Try leaning the main (high speed) needle.
Davidka is offline   Reply With Quote
Old 03-22-2009, 04:04 PM   #3
Tech Addict
Join Date: Mar 2009
Posts: 725
Trader Rating: 12 (100%+)

+1, adjust the main needle first, then you may also need to make a small adjustment to the low speed needle next then the idle position last.
HB D8T with BCE Chassis, ACE Shock towers and motor mounts, M2C Rear Suspension system, KH front steering plate and chassis braces, Lunsford Ti-turnbuckles & hinge pins, OS Speed motor, Hitec 5995TG steering, Futaba 9351 throttle/brake, OS 2060 pipe, and J concepts Punisher Body.
HB D8: CEO Mods Novarossi P5K with JP4 tuned pipe, JR 9000T steering, JR 8800T throttle.
gotspeed_2000 is offline   Reply With Quote
Old 03-23-2009, 08:14 PM   #4
Tech Initiate
Join Date: Jan 2009
Posts: 47

Thanks for the info.
tk1931 is offline   Reply With Quote

Similar Threads
Thread Thread Starter Forum Replies Last Post
OS FS26S-C 4-stroke development mxwrench Offroad Nitro Engine Forum 1763 12-30-2017 03:56 PM
Cyrul's Break in Procedures revzalot Onroad Nitro Engine Zone 156 03-21-2012 03:47 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off

All times are GMT -7. It is currently 02:44 PM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net