Author Topic: K2F waterproofing  (Read 731 times)

Online Kickaha

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K2F waterproofing
« on: 09.02. 2020 05:32 »
Is it possible to waterproof a K2F or would I be better off finding a K2FC and is the Wader the same thing ?

My A10 gets a lot of back road usage and the only week point is river crossings, it seems as though you just need to spit in the general direction of the mag and it cuts out
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Online groily

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Re: K2F waterproofing
« Reply #1 on: 09.02. 2020 07:49 »
'Waterproof' is one of those words! My newest all-singing all-dancing battery-heated winter gloves are, they say, so's my preferred winter over-everything-jacket, designed for offshore fishermen (height of sartorial elegance, that). They're good, but they aren't 100% after say 6 hours of a pissy wet day on unfaired bikes.

So with mags  . . . A standard K2F should be 'shower-proof' using the clothing analogy, and can be made more so with the use of sheathes over the HT pick-ups (and advance/retard cable entry if fitted), with silicon goo thrown in. Goo on the HT pick-up gaskets too. But there are ventilation holes in the mag body underneath, and the contact breaker end will be more or less shower- or water-proof depending on what end cover you have.

A Comp model shouldn't have the ventilation holes underneath, has screw-on pick-ups and cb cover with a breather extension to which a pipe can be attached to take the exit point up and away. It is a better starting point than the standard version because screw-on is always going to be better than clip-on, but crossing rivers in spate would probably still be risky!

Haven't seen the Wader label applied to a K2 mag, I think it's pretty well an NC1 single cylinder tag, but may be wrong.
Bill

Online JulianS

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Re: K2F waterproofing
« Reply #2 on: 09.02. 2020 10:48 »
Had a K2FR with green "Wader" label and another with a red "Racing" label.

Have used both K2FR and K2FC on my A10 but you need to make sure there is clearance between the mag and crankcase cam trough, the standard K2F has a machined chamfer to clear.

Also there is limited space to access the rear pickup retaining screws which can be a pain.

Lucas issued at least 2 bulletins about use of the breather tube - basically if left connected all the time expect problems with the points due to poor ventilation - have attached these bulletins.

Beware ebay mags claimed to be K2FC - some offered are tarted up (to boost the price) standard K2F with screw on pickups (used on some Triumphs) and the ventilation hole underneath mention by Groily. Often there is no photo of the underside so you cannot check.

Online Kickaha

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Re: K2F waterproofing
« Reply #3 on: 10.02. 2020 06:15 »
Had a K2FR with green "Wader" label and another with a red "Racing" label.

What's the difference between a K2FR and K2FC, they look to be the same thing R for racing, C for competition
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Online Kickaha

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Re: K2F waterproofing
« Reply #4 on: 10.02. 2020 06:17 »
But there are ventilation holes in the mag body underneath, and the contact breaker end will be more or less shower- or water-proof depending on what end cover you have.

End cover has the kill button in the centre, so another point for water to get in
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Online groily

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Re: K2F waterproofing
« Reply #5 on: 10.02. 2020 07:12 »

What's the difference between a K2FR and K2FC, they look to be the same thing R for racing, C for competition

Subject to further chapter and verse from Juian  *smile*, I'd say that on the inside, the Rs have -  in the cases I have seen of K2FR and KVFR - an armature with a one-piece drive end in stainless steel, rather than a steel shaft grafted onto a brass end-cheek. That is true for both early15mm and the later 18mm armatures. Serious difference in strength for the drive end, which is a point of weakness on K2Fs, especially on the early ones. Was it the AJS Porcupine that lost a TT owing to armature drive failure, leading to revisions at the factory? Can't remember.
But what is actually in any given instrument after all these years is anybody's guess!

The push-button alloy dome end cover could be swapped for a different sort, with some messing about, but only the Comp type is really waterproof (nb Julian's warning about breathing). A Comp-type end could be fitted onto the later (large screw-on cb cover) standard mag with rectangular housing, but then you've still got clip-on pick-ups and holes in the body.

Ref fitment of non-chamfered mags on As, I've run my swing-arm one with several mags over the years including a C - all have fitted OK without fouling the crankcase casting on mine. Worst thing - in my opinion - is lack of space for advance/retard cable with drip-tray fitted, and difficulty in finding good quality cranked 45° angled front HT pick-up that will clear everything nicely.
Bill

Online JulianS

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Re: K2F waterproofing
« Reply #6 on: 10.02. 2020 09:33 »
The K2FR was a much better built mag than the K2F or K2FC, from the Lucas Racing shop rather than mainstream production. Part number, date of manufacture and a serial number stamped on the flattened part between the 2 pickups. (the K2FC was not flattened here)

Body machined on the underside rather than left as cast.

Many of the parts for the KFR are not listed in the Lucas parts lists.

End stampings shown on first photo.

The stainless armature drive end as one on right in second photo.

Fitted as standard with platimum points (smaller diameter contacts). Third photo one on the left.

The slip rings were different - (the length and position ofthe brass segments differ)

Part 493198 for K2FR ( not listed in parts books)

Part 456727 for K2FC

Part 455361 for K2F.

You will find only the later are now available new, what difference the different one make I dont know have used them all over the years and note no obvious difference in performance.

The K2FR and K2FC screw on end cover with breather is a straight replacement for the K2F screw on cover BUT you will find that the breather extension fouls the lower extended mag fixing nut - you either have to shorten it or loosen the breather part of the cover each time you access the points.

Online Kickaha

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Re: K2F waterproofing
« Reply #7 on: 11.02. 2020 05:34 »
Either way I go I'm obviously going to have to find a mag with the screw on cover and screw on HT leads as stopping every river crossing for 15 minutes to let things dry out doesn't appeal to me
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Offline terryk

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Re: K2F waterproofing
« Reply #8 on: 12.02. 2020 08:50 »
I have a number of those screw on type magys and other K2Fs send me a message Im in Australia.
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