Nope, not all threads are created equal. I suspect an O2 sensor would have pipe threads, if so, a pipe coupling can be had for a dollar & a 4"nipple for not much,, heck, if you know the guy at the store & he doesnt mind, you could possibly return the nipple if you dont have a need to keep it,. Every welder I know has a cut off saw,, cutting the coupling down would take all of a minute,,

weracerc wrote on 04/11/12 at 07:16:10:


Nope, this is the kind of stuff I want to hear. cheaper is always better and free is best!

Concerns with this method: how far up does the probe have to go? would a reasonable shop charge me for this? This would only be able to test the bike at a stand-still, but I could probably check all the fuel circuits (idle to WOT) reasonably well. You'd imagine a shop might do this for free, but they do charge for emissions inspection here (PA) so who knows.

I'd be curious to see what requirements the probe has to be accurate (how far up the tail pipe, how long it has to be there, is heat an issue, etc.).

Bought the cheap-o O2 sensor off amazon for $15 (http://www.amazon.com/Bosch-12014-Oxygen-Sensor-Fitment/dp/B0009IK7YC). Hopefully it doesn't take too long to get here.

It looks like it only has a single wire out, which means that that wire is the positive lead and the negative/ground lead is the exhaust pipe/engine/frame.

My plan is to toy around with the sensor before doing anything irreversible to my header to see if I can get any sort of voltage out of the thing, maybe stick it up the tail pipe and see if that changes anything. Then I'll take it to Lowe's and hunt down a cheap fitting for it, because on second thought, $11 for a glorified nut just seems wrong. I'll bother some buddies of mine with welding skills if I can coerce them into doing me a favor and if not, to a pro welder I go.

here's hoping everything turns out decently over the next week.

Got some advice from a buddy at work that did this for his Nova. There is a lot more theory here than I was anticipating, a lot of which I can't use. Supposedly there is a "sweet spot" for O2 sensors, typically in a short pipe right after the collector for all the headers. We've only got one header, so that makes things simple, but we've also only got maybe a foot of viable length on the header to weld anything in.

I was also told a high-end multimeter should have capabilities to record a graph of voltage output from the O2 sensor. Don't expect me to go drop $400 on one though, perhaps there is one at work I can borrow for an evening....

He talked me into trying to do this myself, rather than take it to a welder. Picked up a 115v MIG welder (flux core only) that I'll try to experiment with. Good thing is that if I royally screw anything up, he should be able to repair just about anything for the cost of a bottle of American Honey whiskey (which, by the way, is mighty tasty on its own or in a glass of iced tea   ).

To sum up: the idea is sound and feasible, though it can get complicated if you want to do it "right" and I'm going to try and fumble my way through welding this thing in myself in the hopes that I don't muck it up too bad  

Hello. My next mod plan is to integrate this meter into the headlight. I will mount the sensor right before the silencer.

K&N sells a complete kit for this, and O'reillys' has a couple of different gauges that don't come with O2 sensors.

For the 'nut', just go to a salvage yard & find a section of pipe after the cat. that you can cut out & get it from. You may even get lucky & find a piece of pipe you can use between the head pipe & muffler.

I don't know if your idea of cheap is $50 or $250, but you could put together something for under $100 using salvaged parts.

RidgeRunner13 wrote on 04/16/12 at 06:42:39:


Yeah, my idea of cheap is <$25, ha ha. the salvage yard is a good idea, I hadn't thought of that one...

Find bolts & lay thread into thread, or, grab a tool, they make a diameter/pitch tool. Not uncommon to see them hanging in the nut /bolt department.

Your SURE it aint a pipe thread? Reeaaalllyyy??