T-Fitting for Oil Sender

[OldGold]

Can anyone tell me the correct pipe size for the oil sender unit on an 80 CBX and where might I find some sort of adapter to install a manual oil pressure gauge along with the sending unit?

Thanks for your help,
Howard

[EMS]

George:

There are sending units out there that provide input for an analog gauge and at the same time for a light. You may want ot explore this.

[bikeymikey748]

Howard, hold that thought. I just saw your post, and am in the midst of the exact same mod. It might be a few more weeks, parts are inbound, but I'll share what I discover if it works out.
For now, the stock pressure switch is a 1/8" NPT male to female thread. There's all sorts of adapters, hoses and such readily available.
I was looking at other options,but plumbing into this area now seems the most workable route.
Stay tuned.

[Kool_Biker]

... just saw your post, and am in the midst of the exact same mod. It might be a few more weeks, parts are inbound, but I'll share what I discover if it works out ...

What I like best about our club!

Aris

[daves79x]

The thread size came up some years ago. If I remember it's NOT 1/8 NPT, but everyone uses 1/8 fittings as it's a close fit and seems to work. I think it's really a metric pipe thread.

Dave

[bikeymikey748]

If I remember it's NOT 1/8 NPT, but everyone uses 1/8 fittings as it's a close fit and seems to work. I think it's really a metric pipe thread.

Dave

Metric thread seems more likely, but as you mentioned, the NPT works very well. Nothing has to be forced into place. Sometimes, depending on diameter and pitch, the difference between metric and standard fasteners is negligible.

[EMS]

Sometimes, depending on diameter and pitch, the difference between metric and standard fasteners is negligible.

That's one bold statement, Mike!

[bikeymikey748]

That's one bold statement, Mike!

Mike, I laugh at bold

I kinda cringed when I typed that, first, comment, but being an honest sort ( mostly) I just had to say it.I would be curious to know what the metric equivalent is though. I'll whip out the micrometer and pitch guages when I get back to Casa Common this evening. It just might be something to ponder over a single malt !
Then again, I assumed that tapered pipe fitttings were standardised for both metric & standard. I have been shown the error of my ways.

[EMS]

Then again, I assumed that tapered pipe fitttings were standardised for both metric & standard. I have been shown the error of my ways.

I think you are right about that. I do not recall a specific "metric" pipe thread from my 36 years of living in Europe. I thought you referred to regular thread sizes.

[daves79x]

All I remember that the kits the original TIMS sold for the sending unit were NPT and upon very close inspection, did NOT match the Honda threads.

Dave

[bikeymikey748]

... did NOT match the Honda threads.

The mystery continues. In my case, the original owner had installed oil pressure and temp gauges in the stock upper fairing. The pressure gauge, mechanical, got its feed from an arrangement at the stock pressure switch passage. He had plumbed into it with, what I took to be, a 1/8" NPT adaptor. This was then threaded into a 'T' fitting that the original pressure switch was attached to, and a thin translucent (Teflon ? ) hose ,with bodged ferrule fittings carried the pressurized oil to the gauge. There were no leaks, other than some 'sweating' from the ferruled fittings. But it looked like a dog's breakfast in that area. The gauge wasn't reused when I built the bike back up, and as the stock pressure switch threaded back into place with no problems, I didn't give it too much thought. 5,000+ kms later, it was nice and dry. It removed easily during the course of this, current, mod. Though, I don't rely on Teflon tape when assembling NPT items, preferring to use Loctite blue on dry bits.
I'm considering braided hoses mounted with 1/8" NPT male to -4 AN male fittings. I've fabbed a bracket and have relocated the 'T' fitting to the LH (rear) coil mount. The plan is for one line to exit the case from the stock switch passage, & plumb into the 'T' fitting. The pressure switch is located there, and a second braided hose leaves from there to a new, smaller liquid-filled gauge. I don't see that the fittings I plan to use should give me any problems ( nice stainless kit at that ) . But....I value what Mike and Dave are recommending. In the end, what are the proper fittings/thread specs, if the NPT items are not ideal?

[daves79x]

The kicker is we used the kit TIMS supplied those many years ago and it worked fine - we were just surprised that the threads didn't exactly match. And to boot, I couldn't tell you what thread it may actually be. Or maybe 1/8 NPT is universal, but due to the nature of pipe thread, there are slight variances in threads from place-to-place. If the fittings seem to seal fine, then I'd proceed. I didn't mean to throw a wrench into the process, just was relaying my experience.

Dave

[EMS]

Maybe the TIM's kit was made in China. These guys don't take accuracy too serious.

[daves79x]

Could be. Let me be clear again - this was the old, original TIMS in New England - not the TIMS we know now. Not making any comment whatsoever on any offerings the current TIMS has.

Dave

[bikeymikey748]

I didn't mean to throw a wrench into the process

Don't know about other folks, but I bet they feel similarly, I never took your input in that way, Dave. Just seemed to me you were offering your, very knowledgeable, insights. That's what the forum is for,no?