TeamOSG

iTrader: (25)

I am breaking in a new motor and thought it was getting dialed in. Noticed that on the last tank when I was hit the breaks, the motor cut out. But starts right back up after a quick bump and idles fine.

Reedy VR 21 with RT4 plug and 30%. Running it rich for the break in with 7 tanks through it.

Any thoughts?

kingcoltzan1

Throttle linkage problem?

Leave the car off, turn on the electrics, take off the airfilter. Peep down the hole at neutral, should be about 0.5mm gap, now apply full brakes. Is that gap getting smaller? If so then thats your problem.

305M3

iTrader: (43)

+1. That would be my guess and something I've dealt with on too many occasions. I can't count how many times "incorrect" throttle/brake linkage setups have caused me headaches...

sickpuppy1

iTrader: (32)

Or a clutch shoe hanging up....in a bind or needs a washer under the shoe. washer between the clutchnut and the bearing...causes the shoe to hang against the bell. they can hang for a second and let go either way. Just another scenario to think about....

GizmoJunkie

iTrader: (5)

Throttle linkage and your idle (air gap) screw is usually the most common culprit. If you havent adjusted your idle screw to keep the carb open, it will simply shut off all air to the engine, causing it to stall. Take note of your air gap when you hit the brakes, what does it do? notice how the throttle link works, and has that spring on it. The idle screw stops the carb from closing.

Also already noted, you could have a clutch or even a flywheel nut problem. I had one time where i didn't tighten the flywheel/clutch nut enough and it would spin on the crankshaft. Since the clutch springs are captured by the groove in the nut (in that particular stock/kit clutch setup) it wore out the ends of the springs. In the end the springs held absolutely no tension on the shoes and the clutch would engage even on the starter box. As soon as i hit the brakes it would stall the engine.

Just something to think about and look into

TeamOSG

iTrader: (25)

Thanks all for the insight.

merdith6

iTrader: (3)

That is the most clearly worded answer to that problem. Nice Job.

jmackani

iTrader: (14)

Or your settings are too rich. A lot guys make the mistake of opening the idle more when the engine is actually too rich on the bottom.

Losimoe

iTrader: (18)

most of the time the throttle linkage wont always shut back to the same idle gap. even with the linkage set correctly. always use a rubber band or a throttle return spring to consistently help close idle gap opening. rubber bands are so cheap, you can replace it every race.