|No matter how bulletproof a drivetrain you build, no matter how tough you tires and wheels, the pesky valve stem remains as a significant weak point.|
|I tried the regular short stems, and the very short little metal ones you can get from race shops and the like.|
Neither worked well, and after breaking 2 valve stems in 3 trips, I decided something had to be done.
|One option is to buy the fancy flush-mount valves from MRT.(http://www.mrtrockcrawlers.com )|
They seem pretty tricky, and require
an extension be threaded on for airing up and down, and I'm not much of
a fan for more small loose parts rattling around.
But really, it's because they cost $5US each, and with shipping, taxes, exchange, and brokerage fees...I'd be looking at $45 Cdn for 4 valve stems!!
There had to be another way....and I was determined to figure out a cheap homebrew way to protect the valve stems.
Some racecar wheels mount the valve stems on the backside of the rim, behind the wheel centre, so they don't get knocked off in "wheel to wheel" racing. I liked the idea, but it would be a giant PITA to air up and down.
Here's what I came up with:
While browsing at one of my favourite places in all the world, the local 18-wheeler parts and service shop, Parts For Trucks (http://www.partsfortrucks.com ) I found some brass valve stems that ranged from about 1.5" to 5" long. I chose some about 3.25" long.
The simple plan was to bend them with my brakeline tube bender and mount them on the backside of the rim, behind the wheel centre, so that they would protrude through one of the "windows" in the rim centre just enough to make airing up and down easy, but recessed enough to be well protected.
The one on the bottom is how they came stock, for $1.36 Cdn each. I used the cheap tube bender pictured to bend them like the one shown.
|This is what it looks like mounted in the rim. I still have to weld up the original hole.|
|How it looks from the backside|
It is critical that you mount them so as to not contact the calliper, or anything else, as the wheel rotates. I calculated that on my Jeep, as long as they didn't sit further "inboard" than the wheel mounting surface, I would have the needed clearance. I checked with a square.
|This is an approximation of what they will look like on the vehicle. that one isn't mounted, just placed there, and you can still see the original valve stem. But the pic gives you a good comparison of original vs. the new "protected" style.|
|All in all, not bad for $5.44 total! Not perfect though - If a clump of dirt, stick, or other debris packs the backside of the wheel, it could clump and wedge between the calliper and the valve stem, damaging the valve stem. But I try to avoid the deep thick goo nowadays anyways. Time will tell how well they work.|
Get a GoStats hit counter