Bungee vs Grove

[LSaupe]

Could use some feedback on the Grove gear (vice the original Bungee gear) on a Model III/IV.

Looks like most have converted to the Grove. Is the Grove that good, or... is the Bungee that bad (or somewhere in the middle).

I will be building a III very soon and could use any feedback people might have who have used both. Obvisouly the Grove conversion is not a trivial expense.

I have flown two Kitfox's (Both IV's) and both had Grove gear, so I dont have much reference for the bungee (other than a Cub, which I know is totally different).

Big question... anyone prefer the OEM bungee to the Grove?

Larry S.

[SkySteve]

Bruce,
Yes to both your questions. The Grove is SO much better it is now the factory standard.

[Av8r3400]

...and no bungees to replace.

[HighWing]

I flew probably the first hundred hours on the bungee gear. Lots of talk back in the day - this was in the late 90s. Some had handling issues with the bungee gear as they routinely came from the factory seriously toed in. There was an article in the "Kitfox Times" that gave a procedure for checking alignment and correcting if necessary. I checked and corrected. Then a couple of guys had bungee failures with the limit cables taking out the Bungee bulkhead. Yes, those little cables could bend the bulkhead.

The bulkhead issue prompted me to go to the aluminum spring gear - not Grove, but Hammerhead. At that time, I had no controllability issues, but greasing the airplane in was not a personal strength.

The difference. The grove will be nearly 20 lbs. heavier. The Grove is an inch or two shorter so angle of attack in three point will be less. Some guys like the increased angle of attack per their short field takeoff routine. The Grove has a wider stance.

Like everything else in life, it boils down to a personal preference. I would guess that at this point in time, given the 40 to 60 kits delivered a month in the early years the majority of Kitfoxes out there are still flying with the bungee gear.

[DesertFox4]

Bungee type gear are not inherently bad. We've been using that design for decades and with proper upkeep they still serve many designs well.

The problem with the early Kitfox bungee gear was in the geometry of the finished product. Most came from the factory with a toe in and camber out condition. This makes it difficult to control anytime the weight would shift during take offs and landings. My model 3 used to dart left or right even in a no wind condition. Add a cross wind and all bets were off as to which set of runway marker lights were in immediate peril.

Granted I was flying off mostly blacktop strips and grass/dirt would be more forgiving of the screwy geometry.

After 300 hours and landings and take offs numbering 1000 plus, I switched to the Grove aluminum style gear and never looked back.
The weight penalty was well worth the piece of mind that you were going to make it back to the hangar with most of the important parts still attached to the aircraft.

[Av8r3400]

Mine was a 12# penalty when all said and done. If I wanted, I could skip a couple cheese burgers and get that back.




(But I probably won't…)

[HighWing]

Mine was a 12# penalty when all said and done. If I wanted, I could skip a couple cheese burgers and get that back.




(But I probably won't…)


Not to Quibble or argue - but....

I have a pair of bungee gear in my hangar with fairings - Fabric with wood trailing edge. Without axles or brakes - just weighed them - they weigh 9.125 lbs. or 9 lbs. 2 oz. Grove currently lists their gear for Model IV as 24.3 lbs. I called them some time ago and asked what they weighed including mounting brackets and hardware. I was put on hold for several minutes and when the nice lady came back I was told 32 lbs. Apparently the weight they post on their site is gear legs only, not including the billet machined mounting brackets or hardware. To be strictly apples to apples, I weighed the four bolts nuts and washers for the bungee gear and they weigh 2.9 oz. so rounding up, the bungee gear weighs total 9 lbs. 5 oz.

Based on the numbers Grove gave me and the numbers from weighing what I have, my estimate on my previous post was a tad generous. It looks now more like a 20.7 lbs. difference.

[tommg13780]

I did a bathroom scales comparison and came up with 19# penalty for the grove. I shall therefore confirm Lowell's more scientific value as correct.

[LSaupe]

Not to muddy the waters, but how about the bush gear Kitfox offers (I assume this is Grove as well)? Weight and performance on par (or better) than the aluminum spring gear?

[Av8r3400]

The "Bush" gear is fabricated 4130 tube, made by Kitfox.

Nothing in common with the Grove gear other than it fits on a Kitfox… :p


Kitfox "Bush" gear

http://www.kitfoxaircraft.com/images/Web%20Pics/radial-web.gif

[LSaupe]

Roger that. Guess I got confused with this post. Does the II shown here have a Kitfox bush gear in actuality?

http://www.teamkitfox.com/Forums/showthread.php?t=5619

[Av8r3400]

That does appear to be the Kitfox "Bush" gear.

There are a couple of others making similar gear using the steel die springs. They are all slightly different from one another.

[Paul Z]

I don't believe Grove makes a Bush Gear, Kitfox makes the Bush Gear. I really like the looks of the Bush Gear!

[kitfox5v]

HighWing LLC makes a bush gear as well. Looks good to me I'm considering.;)