Jon195

Recently I purchased a hpi trophy 3.5. I had a few problems actually getting the car to idle for 15 seconds without the wheels spinning when off the ground. I kind of looked past that put the car on the ground set the idle so the car wasn't edging forward and managed to get the car to idle for 15+ seconds. But when I do lift it off the ground the front wheels tend to rotate slightly.

I'm currently on the 4th tank of the break in procedure and noticed that when I come off roughly half throttle the car will quit?

I have not touched any needles yet as I believe I have not finished my break in procedure. Car sounds abit boggy so I think I may need to tweak the lsn but I'm not sure any ideas?

Thanks
Jon

Apco1

iTrader: (2)

I wouldn't worry about that right now. Too early in the break in process to work about the low speed needle and the idle, those two go hand in hand.

Continue with the rest of the break in, once that is completed set the idle gap to about .5-.7 mm. Do this with the carb restrictor out, if the engine has one. At that point you will need to lean the low speed needle to get the engine to idle consistently. The idle stop screw is really only for fine tuning the idle speed, the majority of the idle speed will be controlled by the low speed needle, leaner for faster idle, richer for slower idle. Always keeping the idle gap in the .5-.7mm range. Once it begins to idle well you can start to tune the high speed needle for top speed. You will likely have to very slightly richen the low speed needle as you being to lean the high speed. Nothing more than a hour or two max I would think. The high speed controls overall fuel delivery.

hope this helps, I just went through this myself and this process worked best for me. If i'm wrong about any of this someone feel free to chime in.

Jon195

Not sure I have a carb restricter.

Today, I let the wheels spin slightly off the ground I put it on the floor and the car would edge forward slightly. I was then able to full throttle (3seconds) then release and the car would not cut out it would idle for 8-12 seconds.

When I completely stop the wheels from spinning off ground - I put it back on the ground hit over full throttle release and then the car quits immediately. Should I carry on the break in procedure and let the wheels spin slightly for the idle? I'm just unsure as this may cause damage.

I'm struggling to get the car to idle without I'd sounding boggish/gurgling before quiting. But when I higher the throttle trim the wheels will spin quite fast. Finding it hard to find a good idling point

jhold87

iTrader: (26)

Good rule of thumb for setting the idle gap is use the end of of a standard paper clip. Once you set it leave it until engine is broken in. Also lean your lsn 1/8 of a turn at a time until it will stay running. Most of the time the factory settings are way to rich even for break in as long as you have a trail of smoke and not overheating your good.