Front wheel valve stem cap hitting fork - Page 2

simpkinsona · #11 09-16-2015, 04:42 PM

Use a plastic cap from your car or bicycle.

TimO · #12 09-16-2015, 10:07 PM

I flipped my axle around on the tire tonight and didn't find I gained quite enough clearance for the yellow cap yet, so I guess it's on to an alternative cap for me.

TimO · #13 09-18-2015, 08:59 AM

Ok, so in 10 years I've forgotten so much about building my RV-10 that I'm overlooking some critical information...

This whole valve stem issue is CAUSED by Van's not sending us the proper wheel for our application.

The wheel we get (for the RV-14A model) is the Matco NW501.25. That is the wrong wheel for use with the tube that is common that we get.

Desser did start making a tube with a short stem that we can use as an alternative, but, if you need one in the field (I have needed a tube in the field before, a year ago), you will be unable to find the proper tube locally. So that is one potential fix.

The better fix is to do this: DO NOT ORDER THE NOSEWEEL WITH YOUR KIT.
Instead, order the wheel direct from Matco and order the wheel number NW511.25, which has the cutout for the stem on the other half. The standard tube will then be useable with the wheel and you should not have valve stem clearance issues.

So I was burned by this twice, and I'm upset with my ignorance in not catching the issue before I mounted the tire. Once you mount it, you're stuck because your wheel is no longer new. If you have your finishing kit, stop now, and do a wheel exchange with Matco so you get the right one.

If you, like me, made this mistake, Matco will be able to help you out. Right now I'm in process of RMA'ing my wheel to them, where they will sell me a new 1/2 of a wheel, and machine my wheel with the cutout in the right area so our stem clears. This will be between $65 and $100 with shipping to get corrected, but you will be happier with it long term.

I'll write again once the wheel is back, and include a pic with the clearance if I can remember.

Tom Martin · #14 09-18-2015, 09:31 AM

Tim
Great information, thank you for sharing. This is not your fault; this is an issue that Van's should look after for it's customers, free of charge. I would not accept this type of error from any other supplier. Using a non standard tube is not the correct solution if a proper wheel is available.
The finish kit is very expensive and for that we should expect the correct parts.

vanduyn · #15 09-18-2015, 02:06 PM

I found a old metal valve stem cap with the extension on it to extract valve stems. Cut off the extended end and wound up with 1/8 inch clearance. I think that should work. What do you think?

Aussieflyer · #16 09-19-2015, 03:27 PM

Thank you everyone for your advice. I tried turning the wheel around for some extra clearance - no luck it still hits. I have used an automotive plastic valve cap and it spins freely now. However my local aircraft engineer pointed out that automotive caps do not comply with airworthiness standards as they could be blown off with pressure. The yellow metal valve cap is a mechanical seal and will stop air escaping. Still not totally happy, for such a beautiful design and build seems a shame to be let down by such a tiny issue.

TimO · #17 09-19-2015, 06:40 PM

I did take my Matco axle off today, drill the anti-rotation bolt hole on the other side, and mount my old Matco NW501.25 (the wrong one) wheel from my RV-10 that I still had around, with my 10 year old RV-10 tube and tire. That one always had a tiny bit better clearance (I think the tube stem was a very little bit shorter) than what the tubes do now. That one does have maybe just under 1/8" clearance when mounted now, if I mount the tire with the stem on the side with slightly more clearance.
I wouldn't call this the total solution, because the reason I mounted my old tire is because I have to ship my new one to Matco for them to sell me a new 1/2 wheel assembly and machine mine so in the end I have the proper NW511.25. But it is nice to see it fit with the yellow cap installed.

I also noticed already, even after just having it mounted for a few days, that the stem had been rubbing on the rim hole just a bit. That tube is really meant to have the stem further back (i.e. penetrate on the OTHER half of the wheel and still come out the same side), and having it mounted on the rim we got you could tell the metal stem wanted not to be in that location. So I will be very happy to have the proper wheel back once they finish.

Anyway, for any builders out there, I'd suggest not buying the wheel or axle with your finishing kit. Just get the axle and wheel from Matco together at the same time, when you order your finishing kit.
The parts you will cancel off your order are the wheel (you can still get the tire and tube from Van's), and also cancel the 2 U-1023, and 1 U-1009 part off your order. Mine are still unused, and I'll be sending it back to them. Heck, I still have mine from the RV-10 after giving up on that assembly there.

On a positive note, I fit my rear window yesterday, and I must say, whoever is producing the plexi for Van's did an excellent job...along with Van's and their sizing of the window. It takes a minute to read through and understand the process you're going to do, but the actual fit and finish of the window is excellent, and fitting it really would take almost no time at all if you know what the goal is. So where some parts like the wheel are frustrations, there are some periods of brilliance, too.

sblack · #18 09-19-2015, 10:01 PM

The solution is obvious: put the 3rd wheel at the back, where it's supposed to be!

TimO · #19 09-30-2015, 05:43 PM

I got my wheel back from Matco today and mounted the tire on it. I haven't put it on the plane yet, but here are some preliminary pics and a report on the valve cap clearance.

As you can see from the first 2 photos, the hole is in the other half of the wheel, which is the way it should be for our installation. Matco sold me a new 1/2 wheel and machined my other 1/2 with the hole, then pulled my bearing races out of the old wheel I sent them and put them in my new wheel half.

In the 2nd 2 photos, you can see a big difference in cap clearance will be the end result. When viewed from the forward side of the tire, you cannot see the yellow valve cap. I had to turn my viewing angle to the side of the tire to even see the cap sticking up. Then I laid a 2x4 on top of the tire, above the stem. The stem still has about 1/8" clearance from the board that is set at the width of the tire sidewalls. Now when you see your tire mounted on the forks, clearly the tire itself has plenty of room so it doesn't hit the fork. So the yellow cap will now be about 1/8" further away from the fork side than the existing sidewall of the tire is.
Much better, and now you can keep your metal hex cap installed.
Hopefully you all can learn from my mistake and save the added money I spent by allowing myself to be sold the wrong wheel in the first place.

Ron B. · #20 10-01-2015, 05:33 PM

Tim , I drilled my wheel hub as I explained to you and enlarged the mouse hole as per Matco for the washer and nut supplied with the tube. Van's tells you remove the nut and washer but they also state if there is a difference in instructions to follow the manufacturers instructions so I wanted to install the tube with the nut and washer. I took most of the evening to get the nut seated properly on the mouse hole. I'm wandering if this was because I modified my wheel or if you had the same problem when you mounted your tire?
Thanks Ron