.21 Engine Question
 

I have two .21 engines (Ninja and Go) and Im tuning them properly but the problem is when Im HOLDING a low- constant rev, even half throttle for a few seconds, and then go full throttle, it loads up rich and then revs out. Ive tried leaning both the top and bottom needles and it still does it.

I can let the engine sit for roughly 15 seconds or more at idle and then go full throttle and it will rev out instantly.

The way I have to drive it to prevent the engine from getting this rich fuel from somewhere is to constantly blip the throttle on and off in corners rather than hold the revs in one spot.

So what can I do to fix this or is this how all engines are?

Your problem seems to be two in reality. First I presume your needles are way off if you could leave the engine sit in idle for 15 seconds and then open the throttle and rev-up without needing to clear your problem is that low-end is too way lean and the LSN is too rich, open your low-end needle and close your high speed needle to correct this.

This could end too in temperature problems just because the low-end needle is very restrictive and doesn't leave fuel just to cool the engine

Second seems to be a driving technique problem and this is really difficult to solve, but is caused by your incorrect needle adjustment. Change your needles adjustment and see if it helps.

Corse-R sounds right, it sounds to me also that the HSN is too rich and the LSN is too lean. Before you start adjusting the engines make sure that you set your idle gap properly. Then tune the HSN (which effects about half throttle up) for performance. Then richen your LSN until it will load up and die after 10-15 seconds of idling (without readjusting your idle yet) At this point drive your car up the street and clear all the fuel out then bring it into your feet count to 6 slowly and then grab the throttle again. Start leaning the LSN until it takes off with only a slight bog and then you can adjust your idle and hit the track.

I dont know because the top end is fine. If I go any leaner on the HSN it will be too lean right at the top end. Right at top end runs fine.

Off the idle its fine. If I leave it for any more than 10-15 seconds it will start to bog when I take off so I know its on the richer side rather than lean on the LSN. But even when I open the throttle very little and creep forward at a slow pace for a few seconds then nail it it bogs down and puffs out a decent cloud of smoke before clearing out.

So the very top is fine and off the idle is fine. If I change any needle settings its going to stuff these areas up. Its the parts inbetween when holding the revs in one spot for a few seconds.

Have you tried to change to a hotter glowplug?

Good luck!

Yes i use a OS P3 which is the hottest in the range I think.

Dont get me wrong the engine runs really good overall, its just when holding a rev for a while then accelerating more it comes out rich and bogs. If I dont keep the engine on the same rev for too long its an absolute rocket.

Which engine is giving you the problem or both. The engine should not be able to sit and idle for 15 seconds and then just be able to take off.

change the balance of the needles toward the top a little to better suit your "electric" trigger finger bro . richen up the top end needle about 3 hours to start ,then lean the bottom a little (would be more specific but all carbs that aren't novarossi are different) keep the idle as low as possible and listen for no more than 2-3 seconds of runout (idle up) when coming off throttle :nod:
pm me if you need more help ,
MONTY