What kind and size of thread?

I am looking to put a oil pressure gage on my 1978 KZ1000. On the right hand side of the motor there is a plug above the points cover. This is the place where most of the oil pressure gages go. Anyone have an idea of the thread side so I can order a chrome adapter?

This has been discussed before. I had thought this thread was NPT (national pipe thread) but someone mentioned it was metric. I do know that most autoparts stores that sell oil pressure gauges also sell "adapter kits" which contain a variety of adapter sleeves to adapt NPT to metric, etc. I have used oil pressure gauges on most of the bikes I have owned in the past but don't really feel it is a great idea on a KZ since the 903/1015cc KZ engine is low pressure. The gauge should read no more than 15 PSI else its scale will be meaningless... such as a 60 PSI Harley gauge. Since you will be under 5 PSI most of the time, it would hardly show on a Harley gauge. I used a 100 PSI gauge on the last Vulcan I owned as they are high pressure oilers. I think an oil temp gauge would be more useful on a KZ. If you do a search, you could probably find the old thread where the thread pitch is discussed.

Post edited by: wiredgeorge, at: 2007/02/14 08:24

wiredgeorge wrote:

This has been discussed before. I had thought this thread was NPT (national pipe thread) but someone mentioned it was metric. I do know that most autoparts stores that sell oil pressure gauges also sell "adapter kits" which contain a variety of adapter sleeves to adapt NPT to metric, etc. I have used oil pressure gauges on most of the bikes I have owned in the past but don't really feel it is a great idea on a KZ since the 903/1015cc KZ engine is low pressure. The gauge should read no more than 15 PSI else its scale will be meaningless... such as a 60 PSI Harley gauge. Since you will be under 5 PSI most of the time, it would hardly show on a Harley gauge. I used a 100 PSI gauge on the last Vulcan I owned as they are high pressure oilers. I think an oil temp gauge would be more useful on a KZ. If you do a search, you could probably find the old thread where the thread pitch is discussed.<br><br>Post edited by: wiredgeorge, at: 2007/02/14 08:24

I have a question on this same subject. My bike a KZ1000 when I got it had a gauge already installed there. The plug was drilled and tapped for what looks like a 1/8"NPT. My problem is when I took the engine out of the frame I broke the gauge off at the plug and it also broke the flats on the plug off. Now I have a hole where the gauge and plug used to be. Other than grind the broken parts off and intall a 1/8"NPT plug in the hole can I buy a replacement OEM plug?

Check a catalog such as McMaster-Carr or Grainger... They have all sorts of plumbing fixtures, plugs, nipples. Something they have should fit your need.

Thanks Grantl, I was interested in finding the flange type plug that was originaly in the block. My last resort would be to just plug it with a standard pipe plug.

In San Antonio, there is a store that sells hydraulic hoses and fittings and they carry just about every type of fitting you can think of. I can't recall their name but suspect that most large towns have these places. In addition, any autoparts store that sells the adapter kits should have a fitting in the kit that will work and the kits are not expensive. If memory serves most of the adapter fittings are brass.

Thanks Wiredgeorge. By the way I will be dealing with you in the near future with a set of carbs to be gone over.

Chris78LTD wrote:

.... Anyone have an idea of the thread side so I can order a chrome adapter?

Hi Chris and welcome to KZR.
The fix for anything broken is tough without seeing it. That said, when you do get things cleaned up and are to the point where you need plugs or gauges, you can buy or borrow a thread pitch gauge which will fit into a hole for inside threads, and will of course measure outside threads as well.

Post edited by: JimatMilkyWay, at: 2007/02/15 10:54

Hello all,

VDO Electric Oil Temperature sender; 0-300 Degrees; VW Bug drain plug; M14X1.5; screws right into the oil galley like it was made for it. The inside end of the sender does not block the internal passage.

I bought mine on Ebay for 14.99 a couple of months ago. There are some on Ebay right now! They also are available in Porsche M18X1.5 which I believe will fit the KZ drain plug, but don't quote me on it.
Hope this helps!
Regards

Here's a link to a pretty informative thread on the topic:

Link To Older Post

Renobruce seems to have a good handle on what it takes to fit a gauge to the KZ's. (I think he sells the kits on eBay, but I don't think I'm allowed to mention that, so I won't )

Let me rephrase. The sender unit fits into my J Model engine oil galley absolutely perfectly without even the slightest hint of slop or over-tightness. How it might fit for you or any other I could only guess.