Hi guys, I'm new here. this looks like a great forum.
I am building a Murphy Rebel and decided to get some Goodyear 8.50x6 tires for it so I can join y'all in the backcountry. That has created a bit of a problem. The wheels that came with the kit are made by Murphy and are 3 piece with 6 bolts, and are pretty nice looking. Here's the problem: they are designed for a 90* valve stem. It seems that Murphy wanted to supply cheap lawnmower tires and tubes with their kits, and so designed the wheels for those. I stupidly didn't realize when I ordered my aircraft tubes that they have straight valve stems and won't work. I have searched exhaustively and from what I can tell there is not a real aircraft tube made in this size that will fit my wheels. I would still like to use the Goodyear tires, so I have 3 options as I see it. 1-use cheapo 8.00 lawnmower tubes and hope they don't blow. 2-buy new wheels and try to make them fit my axles already built into the gear. 3-try to run the Goodyears tubeless. Right now I like option 3. I am pretty sure I can make the wheels airtight by using a rubber rim-strip, and 90* valve cores are easy to find. The tires aren't specifically designed for tubeless, but they sure look tough enough for it, and this is experimental remember. I have been running my mountain bike tubeless with non tubeless tires and Stans No-Tubes for a couple years and I really pound it off road. No puncture or pinch flats, and you can run really low pressure. This is not a mountain bike but...
Any advice appreciated. Thanks
Jesse

Jesse,

Congratulations on a BIG project! The Rebel looks like it would be a fun airplane. I've flown one Super Rebel a bit, and I liked it.

As to the wheel question: I would not try to run an aircraft tube type tire as tubeless, frankly. You are into serious test pilot mode there, and consider what the consequences are if it fails at an inopportune time. These tires just werent' designed to be operated as tubeless tires.

Considering the amount of time, energy and money you have in the plane, I'd strongly suggest buying a set of Cleveland wheels or similar certificated wheels, and install them. If the Murphy axles are anywhere near standard (1 1/4 inch or 1 1/2 inch) this should be easy, except maybe on the pocket book.

MTV

Jesse,


Give Desser Tire a call at 1-800-247-8473 they use to be able to supply non-std tubes with a 90 degree bend.

Rebelbuilder,
Do you subscribe to the rebel builders list? There was a recent discusion on the same quesion you have asked. I believe someone said that Murphy has changed the design in their wheels because of this problem. There was also a response on where to get tubes.

Keith

Thanks Guys,
Yes it is a big project. I've been building for almost 4 years and probably have one more to go. I will keep looking at some new wheels. I have 1 1/4" axles. I think the problem will be with the torque plate/caliper/axle interface. I will probably have to make custom torque plates because it seems there is no standard bolt pattern among manufacturers. I am looking at Grove wheels right now, but I will check out the others as well.
I got my tires and tubes from Desser, and have talked to them several times since, while trying to figure this mess out. They do have an "experimental" 8.00x6 tube with a 90* stem, but from what I can tell that is the same lawn mower tube available all over the web for about $20. I have some on order from Wicks already just to see what they are like. I talked to a CH801 guy who went through the same problem, and used the cheapo tubes. He had 4 blowouts in 6 months and the last one sucked him into the water while landing on a gravel bar. After that he modified his Matco wheels to take real tubes. BTW Murphy offered to sell me the equivalent cheapo tubes for $90. each. There's factory support for you! Funny thing is they say the wheels are approved for 8.50 tires.
Yes I am on the Rebel builders list. That was me asking the question on there. A few guys told me to go ahead and use the cheapo tubes, but I don't think anyone on there has actually done the same tire/tube combo I have. After talking to the CH801 guy I am very skeptical.
It seems like I can't get there from here if you know what I mean. Unless I pay for the bridge to be built.
Thanks again. If you have any more ideas please keep them coming.
Jesse

Go with the Clevelands, and look at 8.00's, not much smaller really, but much lighter, or AK bushwheels has an experimental wheel and tire I think, but I don't know it's weight limit. Give em a call, can't hurt and I think they may be tire / wheel experts.

Not sure you want to spend the greenbacks on bigger tires but a64pilots suggestion of AkBushwheels is a good option. I recently purchased a set of the AkBushwheel 26 inch Airstreaks and put them on my Champ. They will be going on my Rebel....whenever I finish it. They are 19-20 lbs each so they don't weigh anymore than the 8.50's.
Another benefit of these tires is there is no tube to have to worry about like with the 8.50's. I ran 8.50's on the Champ but had a paint mark on the wheel and tire to check to see if the tire was spinning on the wheel. For such light planes the airpressure has to be run fairly low to get much benefit out of these tires. I had also tried the 26 inch Goodyear "Blimp" tires but the sidewalls were very stiff for use on the Champ. I think I could have gotten by without even putting air in them!
Good Luck!
Keith

Hi Keith,
Which wheels are you planning to use with the Bushwheels on your Rebel?

I was hoping to use the wheels that came with the kit. But I'm a long way til I have to make a decision so that may change. They should work though since they are a 6 inch wheel.
Keith

I took A64pilot's advice and called AKbushwheel. I wish I had done that a week ago. Can I tell you guys how nice it is to talk to someone who is knowledgable and willing to hand out free advice. Definitely not what you get when you call a big store. Anyway, they told me I can cut off the straight valve stem on my tubes and glue on a 90* one. Problem solved. Except now I wish I would have waited for the A.B. 8.50s to come out.
Keith, they also told me the Bushwheels should work fine on the Murphy wheels. I didn't realize that the valve stem comes out the sidewall of the tire, so you avoid any of the issues I am dealing with.

So pop for the 26" ABW airstreaks. Only $2K. 1700# gross weight limit though.

Rebelbuilder,
Dumb me...I guess I should have explained about the valve stem. Something I thought was commom knowledge, wasn't. This was one of the reasons I was trying to explain why I had bought their tires...no valve stem shearing problem and no tube to worry about.
Keith

I'm sure it's common knowledge to all you guys but I'm just learning.
Zero.one.victor, I was seriously thinking about the 26s, but I have my 850s in hand so I will start with those. BTW, I'm from Port Townsend too! Give me a PM, maybe we know eachother. It's a small town.
Jesse