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Discussion Starter · #1 ·
any one know the size and thread of the part of the fuel tank that the fuel petcock threads onto? I have a 72 K5
 

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I think that 66Sprint would be your best bet on that one. I suspect it would be fine metric or somthing called JIS Japanese Industrial Standard, but I am guessing here.
 

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Sensei
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It's DEFINATELY NOT an NPT thread....NPT is US pipe thread and has a binding taper....
The petcock has LEFT HAND metric MACHINE threads, but I am unsure of the size.....
The tank "bung" is the same diameter, but right hand thread.....
When you spin the nut, it pulls both sections together, sealing against the rubber ring.

Metric threading is: diameter in mm X number of threads per mm... Should be easy enough to measure it ....
 

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Discussion Starter · #5 ·
well i guess i will do some measuring this weekend when i go to my storage. I was just wondering if anyone would have to info off hand. I do appreciate the responses.
 

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Sensei
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LOL....I'd have measured for you IF I could get to my shop.... (Darn work!)....I have a new bike there (CL450 Honda) I've not seen yet myself.....LOL... :lol: Steve
 

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Discussion Starter · #7 ·
66Sprint said:
LOL....I'd have measured for you IF I could get to my shop.... (Darn work!)....I have a new bike there (CL450 Honda) I've not seen yet myself.....LOL... :lol: Steve
Must be nice to know you have a new bike some where you havent seen yet....LMAO.
 

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Sensei
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New to me..... It's an old rag.......

But it does have Koni shocks and a good front drum....LOL....
 

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Discussion Starter · #10 ·
wow...pristine..but thats how my K5 was when it was given to me....so i understand what you mean when you say "new" :D
 

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Sensei
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Yep....some of my "best result" bikes started out looking worse than this.....
The Koni's, good front drum, lower tree (stem and bracket) set up for a steering damper, and paperwork are worth the $175 I paid.....Everything else is a bonus.... I can't wait to open up the engine and see what's good inside it...... ;) :D :lol:
 

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66Sprint said:
New to me..... It's an old rag.......

But it does have Koni shocks and a good front drum....LOL....

The seat fits nice!!
 

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Sensei
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LMAO..... That already hit the trash pile......
AND, were are far removed from the original question....Which I'll attempt to answer Monday when I really start stripping her down....
 

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Discussion Starter · #14 ·
thats cool...i was inquiring of all this because i was considering a Pingel with a dual outlet to replace the stock petcock. The fuel inlet on the Mikunis i am reinstalling are about .315 so thats about 5/16 (.312) of an inch. The outlets on the factory petcock are much smaller. I will be using Tygon transparent fuel lines.
 

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Sensei
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I wasn't aware Pingel manufactured any metric petcocks.....
 

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66Sprint said:
LMAO..... That already hit the trash pile......
AND, were are far removed from the original question....Which I'll attempt to answer Monday when I really start stripping her down....

I notice you have a trash can centered in the photo. Was the intentional or subliminal? Just kidding, it is truly amazing what the talented folks like your self can do with these! I feel blessed I got a nice running and rider that passed inspection for $600. The work I will do is one little thing at a time.
 

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Metric threading is: diameter in mm X number of threads per mm... Should be easy enough to measure it ....
Not to be picky, but . . .

It would be more correct to say that a metric thread is the nominal outside diameter (for an external thread), followed by the number of mm per thread.

Metric thread is actually designated using pitch (sort of the inverse of what we are more used to in the U.S.A.: threads per unit of distance). Pitch is the distance in mm from any one point on a thread to the corresponding point on the next thread, when measured parallel to the axis of the fastener. The reason for this is that since the base unit is a millimeter, which is only about the thickness of a dime, it would be tough to count how many threads occur within that distance. :geek:

I measured my tank outlet threads directly above the petcock on my '71 CL350K3 and on my '70 CB450K3 and both appear to be M16x2. Since the pitch is usually only stated if a fine thread is designated (for example: M16x1.5), the coarse thread would simply be written as M16, and it would be assumed to be a standard coarse thread.
 

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Sensei
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Please be picky.... I don't want to distribute incorrect information, even if accidentally... You are explicitly correct.... ;)
 
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