Tuning problem

[alien13]

Got my new carb in today. I'm pretty close to having a good tune, but I can't get a low idle. Not only that, but when the tires stop, it shuts down.

This is on a Losi 3.4 in a Speed NT. I had to lean it out almost a full turn to get the temps up, but then they started to spike at 230+. Turned it back down, still have a little bit of adjusting to do on the high side.

In the first picture is the low speed needle

Second picture shows the high speed needle (top) and the Idle Stop Screw (tucked down inside to the left of the high speed needle).

Where do I go from here?

Also, using a laser temp gun, what is the best place to get an accurate reading?

 

[Metalhead Matt]

Sounds like a broken clutch spring.

 

[alien13]

Sounds like a broken clutch spring.

Clutch works fine, when it idles low. The problem, is that the idle is too high.

 

[hamz9561]

The place that I've seen being checked the most is on the area right around the Glow plug. 230* is not too bad a temp for most nitro engines.

The idle adjust screw needs to be adjusted so that there is a gap of about 1/2 to 1mm of gap in the carb at idle.

 

[alien13]

The place that I've seen being checked the most is on the area right around the Glow plug. 230* is not too bad a temp for most nitro engines.

The idle adjust screw needs to be adjusted so that there is a gap of about 1/2 to 1mm of gap in the carb at idle.

Good, that's where I'm getting my temps. I have the idle adjust screw all the way in, tight! And that's about 1mm.

I think I have everything set right now, was just out there buzzing around a few minutes ago. Now I need to tune the suspension and add weight to the nose. Seems after tuning the motor, there's a ton more power than there was at the stock tune! I can barely keep the wheels on the ground.

 

[alien13]

 

[Scrogg]

If you had to turn the idle screw in until it was tight, you went way too far. Properly set, the idle gap is barely visible.

 

[Mickstix]

Looks good on the video! If ya dont already, you should buy or make a wheely bar for it.. Keep it from flippin over so easily..

 

[alien13]

Looks good on the video! If ya dont already, you should buy or make a wheely bar for it.. Keep it from flippin over so easily..

Lol, it already has a wheelie bar. I'd rather put more weight down on the front.

 

[Scrogg]

Runs strong no doubt! Pretty damn fast! I could not watch the vid earlier, I was at work. They block youtube...

 

[alien13]

Runs strong no doubt! Pretty damn fast! I could not watch the vid earlier, I was at work. They block youtube...

Still need to lean it out a little bit on the low end, but otherwise it feels good. Now I need to work on weight transfer. I want the front end to stay on the ground. I'm thinking maybe a set of rear tires for an 1/8 scale might do the trick.

 

[Scrogg]

I was thinking it was a tad rich on bottom too, but it does not seem to mind. Stick on lead weights, stop by a auto service station and see if they will give you a few. !/8th scale tires will change the gearing, so you will need to compensate maybe. They could cause a bog off the line from the extra weight and rolling diameter.

 

[alien13]

I was thinking it was a tad rich on bottom too, but it does not seem to mind. Stick on lead weights, stop by a auto service station and see if they will give you a few. !/8th scale tires will change the gearing, so you will need to compensate maybe. They could cause a bog off the line from the extra weight and rolling diameter.

I'll look into the stick-on lead. I looked at some 1/8 tires, and they are bigger than I thought.