Are 1/4" NPT Petrol Taps compatible with BSP Threads

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Pingel makes a high flow Off-On-Reserve with 1/4 NPT, but not BSP.

I called and spoke to someone at Pingel to see if I could get a one-off. Answer .... No, but the guy said they get a lot of such calls and were considering offering a BSP version.

Perhaps if enough of us contact them, we can push them into production.

They are pricey, however ..... in the $125 US neighborhood.

Slick

BTW ..... you can run a BSP die over 1/4 NPT, or 1/4 NPT tap into a tank bung (forever ruining a tank), but as FE says, that is a bodge. I would not do it.
 
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I am looking for a combination main/reserve tap for use with Amals, so with a vertical outlet.

Has anyone seen such a beast that fits Commandos?
 
Only my view, but NEVER screw a NPT petcock or run a tap into a tanks port on a british tank.
I have researched this petcock issue a lot starting 30 years ago. Especially because featherbed tanks have only one outlet. For the price of a 1/4 BSPP die you can do a "conversion" in a few seconds to a NPT petcock. No one else will know unless you tell them.

Being selective of the washer thickness will affect the rotational angle it points. though I don't use side exit petcocks. I sometimes make a thick teflon washer (screw-on spacer) and tap it with 1/4BSP. Then thin it down until the lever points the way I want, which is especially important on a featherbed petcock. Better than teflon tape (GAG).
 
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I am not interested in spacers, or changing the threads. I am more interested in an existing combination main/reserve petcock with a vertical outlet that is threaded BSP.
 
gortnipper said:
I am not interested in spacers, or changing the threads. I am more interested in an existing combination main/reserve petcock with a vertical outlet that is threaded BSP.
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I have not found one in BSP threads. See reply #21, and reply #24.

Let me know if you find one. I have gotten my self out of the woods by making a teflon "cork" for my original Ewarts, but I feel it is time to modernize the fuel tap.

Slick
 
Fast Eddie said:
No experience of these, but they seem to fit the ‘wanted’ description:

Triumph BSA Norton Univeral Motorcycle Petcock With Reserve

Heavy duty, three position, 1/4 National Pipe Thread fuel valve Fits: Universal fit on any 1/4 NPT fitting Triumph, BSA, Norton (see note below) Features:
www.mapcycle.com www.mapcycle.com
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Not quite..."Many vintage Triumph, Norton and BSA tanks use 1/4" BSP (British Standard Pipe) thread rather than NPT, so these petcocks will not thread completely into a tank with a BSP fitting."

But, may do for running a die over...
 
When I am cleaning out a Triumph, Norton, tank etc, I remove the petcocks and gently run in a brass 1/4" NPT plug, wrapped generously with teflon tape. Then I can go nuts with the usual collection of hardware, soak it in various cleaning materials, etc.
The threads are close enough, the brass is soft enough, and I use a light hand when tightening. Never leaks, no damage to either the internal or external thread.
To be clear, I am not suggesting this is okay with a petcock, but it is a handy shop trick for cleaning out a tank.
 
gortnipper said:
Not quite..."Many vintage Triumph, Norton and BSA tanks use 1/4" BSP (British Standard Pipe) thread rather than NPT, so these petcocks will not thread completely into a tank with a BSP fitting."

But, may do for running a die over...
Click to expand...
The MAP petcock example is exactly the petcock type I discussed in the "other norton" forum a year or more ago. It's use is desireable for featherbed/slimline tanks with only one fuel outlet.
An OFF/ON/RESERVE valve made by american company DAP co. They do a lot of OPE valves.
Only the flow rate is my concern for making high horsepower out of a stock single tap slimline tank.
 
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The Pingle are the taps to use if fuel flow is your concern. They outflow all others that I have looked into.

dynodave said:
The MAP petcock example is exactly the petcock type I discussed in the "other norton" forum a year or more ago. It's use is desireable for featherbed/slimline tanks with only one fuel outlet.
An OFF/ON/RESERVE valve made by american company DAP co. They do a lot of OPE valves.
Only the flow rate is my concern for making high horsepower out of a stock single tap slimline tank.
Click to expand...
Flow rate was my concern also, especially trying to feed two Amals off a single tap. I found the Ewarts tap was adequate, but the standard Amal needle and seat (0.125 orifice) was not.
See https://www.accessnorton.com/NortonCommando/flow-measurements-on-ewarts-fuel-tap.21225/

The needle and seat orifice is the bottleneck.

Slick
 
dynodave said:
The MAP petcock example is exactly the petcock type I discussed in the "other norton" forum a year or more ago. It's use is desireable for featherbed/slimline tanks with only one fuel outlet.
An OFF/ON/RESERVE valve made by american company DAP co. They do a lot of OPE valves.
Only the flow rate is my concern for making high horsepower out of a stock single tap slimline tank.
Click to expand...
My bike is a bit hotted up and uses larger jets with the needles up high to get the appropriate mix that isnt too lean (nor sooted), so I also worry about delivery flow rate - especially towards the end of a tank.

With my alloy tank, it has a long neck out of the tank body, so my Main tap really leaves next to no reserve. So, the standard main and reserve taps are ok to run for both at once - effectively I have no reserve anyway.

I am looking to recommission my Interstate tank for couple thousand K ride coming up, and I would like to still run both taps on main, but still have an effective reserve.

Do you have a link for the Dapco taps?
 
gortnipper said:
Not quite..."Many vintage Triumph, Norton and BSA tanks use 1/4" BSP (British Standard Pipe) thread rather than NPT, so these petcocks will not thread completely into a tank with a BSP fitting."

But, may do for running a die over...
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Ooops... missed that. Probably why I accumulate so much stuff !

These boys used to make a very nice high flow tap, I used the 2 position before but they also did a 3 position (I think). Can’t find anything on their web site now though, might be worth an email:


Then again, Interstate taps are further forward IIRC, you might just be ok with the 90 degree 3 positions taps Matt sells?
 
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gortnipper said:
I am looking for a combination main/reserve tap for use with Amals, so with a vertical outlet.

Has anyone seen such a beast that fits Commandos?
Click to expand...

I use a couple of sets of these, each tap has on/off/reserve :- ebay number 183927964798
 
texasSlick said:
The Pingle are the taps to use if fuel flow is your concern. They outflow all others that I have looked into.


Flow rate was my concern also, especially trying to feed two Amals off a single tap. I found the Ewarts tap was adequate, but the standard Amal needle and seat (0.125 orifice) was not.
See https://www.accessnorton.com/NortonCommando/flow-measurements-on-ewarts-fuel-tap.21225/

The needle and seat orifice is the bottleneck.

Slick
Click to expand...
I would think the original Ewerts taps flow well enough, but there are several copies that don’t work as well. My ‘72 750 roadster with combat engine in 1973 ran great on those Ewerts taps to well over 100mph.....I was 20 then. I notice the BAP taps on my current combat roadster don’t flow as well when I’m draining the gas tank.
 
trident sam said:
I use a couple of sets of these, each tap has on/off/reserve :- ebay number 183927964798
Click to expand...
Yeah, that would do it. 24 pounds each, yikes!

I also found these last night, I wonder how the two compare?

Trials Bike Parts :: Carburation & Fuel :: Fuel Taps :: 1/4" BSP - BAP Type Fuel Tap with Spigot Outlet and Filter - MAIN - ON/OFF/RESERVE

1/4" BSP - BAP Type Fuel Tap with Spigot Outlet and Filter - MAIN - ON/OFF/RESERVE This tap has a 1+1/2" tube allowing reserve fuel to remain in tank. 1/4" BSP tap thread Includes a screw in plastic filter, locknut and copper washer. Viton seals - Ethanol
www.feked.com www.feked.com
 
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Flow from the MAP cycle style, DAP co, Dexter MI OFF/MAIN/RESERVE 1/4NPT (tank) 5/16 hose-.1375" outlet port
rethreaded to 1/4 BSPP, installed on a BSA tank
timed 60 second flow directly out of single petcock:
main 490ml
reserve 460ml
 
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