What modifications are required to put a OS .40 4-stroke in a Mad Force.

Does it already have a 21 in it? Yes? you will need a collet for the FS.40 (8mm shaft) or Kyosho makes a 2 shoe keyed flywheel for the .40 and an exhaust system. You will need the biggest clutchbell and the smallest spur gears available. The .40 tops out at 21,000 rpm's and doesn't like to be run without a heavy load or you will float the valves. Other than that, Have fun and good luck.

Would you please explain "float thie valves" please?


I dont know how the R/C 4 stroker works.. does it have a camshaft and the usual spring loaded valves?

Whats the difference between the real deal and R/C 4 strokers?

Thanks man!
ram

Float the valves is when you have more rpm's than the valve springs can respond to, so the valves will float instead of closing all the way. This can lead to broken valves, pushrods or rockers. This mostly happens when you do not have enough load on the engine and it is allowed to over-rev.
Yes. (click the pics for more info)


Not much, but they are more like a diesel engine than a gas engine. (the glowplug thing)

Thank you for your amazingly detailed response

Thatt engine sure is a beauty!!
Floaty valves.. exactly what the word floaty means lol

I see what you mean now!

Thanks!!
ram

Thanks

I thought valve float was when the lifter leaves the cam shaft then smashes back into the cam at the bottom?

When you float a valve, the valve doesn't close because the valve spring can't react fast enough. Since the valve is still open when the lobe has rotated to a point where the valve should be closed, there is play between the push-rod, rocker arm, and the lobe. You can't have one without the other.

Ok i see. A gokart racer told me i could float the valves on an engine i was building unless i got good springs to hold the lifters down. I guess thats what he meant.