Clutch for c box

[rlmankins 1]

Anybody use a clutch for their c box. Was at airport, my buddies north wing weight shift has the clutch. Starts, idles, clutch engages smoothly. Seems pretty nice. Any reasons against using this?

[Av8r_Sed 82]

I'm using the RK400 clutch with my 582 and C gearbox. It has been flawless and has smoothed out startup and idle with my 2 blade IVO medium. It would be great with floats.

[rlmankins 1]

I'm using the RK400 clutch with my 582 and C gearbox. It has been flawless and has smoothed out startup and idle with my 2 blade IVO medium. It would be great with floats.

Thanks, one more item on the to do list.

[Guest]

Anybody use a clutch for their c box. Was at airport, my buddies north wing weight shift has the clutch. Starts, idles, clutch engages smoothly. Seems pretty nice. Any reasons against using this?

There is one good reason not to use a clutch. The spinning propeller acts like a giant brake so should the motor stop while flying, the plane will glide like a chrome plated manhole cover. So while a clutch has many benefits, the benefits have to be weighed against the drawback for your particular type of flying. This said, I have never flown behind a clutch so this comes second hand, but it does make a lot of sense that even a free spinning prop will be a huge brake compared to one that is not spinning.

Chris Bolkan

[Av8r_Sed 82]

Well, I haven't fallen out of the sky yet. I might not win a glide contest against a non clutched A/C, then again, I don't float much on landing. It's really not much of an issue.

[Guest]

Well, I haven't fallen out of the sky yet. I might not win a glide contest against a non clutched A/C, then again, I don't float much on landing. It's really not much of an issue.

Hi Paul,

My post was not intended to say a clutch is bad or that you or anyone else would fall out of the sky. Or to pipe in sounding like a know it all. I think clutches are very cool and almost got one myself once. I was just trying to answer his question regarding drawbacks and let him know there is a cost to installing a clutch, even though there are numerous benefits. Just want him to know there is no free lunch! I hope I did not offend you!

Chris

[Av8r_Sed 82]

No offense taken. The only other drawback is about a four pound weight gain on the nose. Avoid operating in the range of 2200 to 3000 RPM while on the ground so as not to wear on the clutch lining.

[herman pahls 9]

After 500 hours without a clutch I cannot imagine flying a 582 without one.

I do not miss the start up and shut down gear box rattle and prop shake or high idle speed.

They say a windmilling prop has more drag than a stationary prop if engine out.

I have not done any scientific tests to compare but the windmilling prop does not seem to reduce the engine out glide on my Model 1 Kitfox.

Herman

[SuberAvid 617]

I'm surprised Leni hasn't replied on this one. He has a clutch on his and it is pretty nice when we are preheating and starting our planes at below 0 temps; once he gets his started it just idles and warms up with no spining prop. Leni is out walking around his plane checking things and loading gear while I am having to sit in the plane while mine is running to keep from getting frostbit with the blast or worse. I can see where it would be even more of an advantage on floats.

[rlmankins 1]

So I was speaking to my engine rebuilder and he was not that big a fan of clutches. I was not sure exactly why. Some of his comments. No vibration dampening because no rubber torsion ring, prop strike will cause crank problems, wear issues in clutch engagement parts, and I guess this goes along with that, having to rebuild clutch frequently. Also said novice installer might have difficulty installing.

Any comments?