REPAIRING KIPS VALVE STEMS

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NOSHER
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REPAIRING KIPS VALVE STEMS

Post by NOSHER »

ANYONE FOUND A WAY OF REPAIRING THE STEM/OILSEAL AREA ON THE KIPS VALVES TO REPAIR THE GROOVE MADE BY THE OIL SEALS----4 NEW KIPS ARE £2OO !!! :shock:
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JanBros
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Re: REPAIRING KIPS VALVE STEMS

Post by JanBros »

place new seals but don't push them all the way down, push them about 2mm less down

or take the head off and mill the holes a bit deeper.
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Re: REPAIRING KIPS VALVE STEMS

Post by NOSHER »

Thanks Jan yes never thought of that so that means both the seal “lips”are sealing on ungrooved shaft areas .
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Re: REPAIRING KIPS VALVE STEMS

Post by JanBros »

or buy one of my heads, in which you can stack 2 seals on top of each other 8)
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500bernie
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Re: REPAIRING KIPS VALVE STEMS

Post by 500bernie »

Or fit a sealed bearing instead of just a seal.
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Re: REPAIRING KIPS VALVE STEMS

Post by NOSHER »

Thanks for the reply Bernie I think I’ll give that a try sounds good—now where did I leave that vernier guage :?:
Col.
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Re: REPAIRING KIPS VALVE STEMS

Post by NOSHER »

HI BERNIE I MANAGE TO SOURCE THE 2RS BEARINGS TODAY FOR THE KIPS VALVES---- DID YOU USE ANY ADHESIVE TO KEEP THEM IN PLACE OR DO THEY STAY STATIC ?
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Re: REPAIRING KIPS VALVE STEMS

Post by 350S2 »

Bernie & Nosher: are you satisfied with the sealed bearing set-up?
No leaks between the axis and bearing? De the seals survive?
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Re: REPAIRING KIPS VALVE STEMS

Post by NOSHER »

HI WELL IN JULY 2021 the exhausts were literally spraying oil out of the cans and I figured the crank seals had to
Be replaced.so I dismantled the engine after removing it from the frame of course ,packed it up and sent it to PJ ENGINEERS for a crank rebuild .on its return I assembled it using the photos I had taken of the disassembly and was happy to find I did not have so much as a washer left over!!! On Boxing Day 2021 I bit the bullet and decided to attempt it’s first start.I prayed to everything that was open on a Sunday gave it a good prod and it burst into life and burbled happily on tickover.I was so elated I forgot to open the garage door and almost
Choked to death on the smoke.since then I have only taken it out for a 5 mile round trip without thrashing it BUT I have noticed that the bearing outer faces have black oil mist on them so I would guess that the rubber bearing seals do not seal completely.
YOU GET MORE POKES WITH TWOSTROKES !!

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Re: REPAIRING KIPS VALVE STEMS

Post by NOSHER »

Oh yes Bernie when I was reassembling the engine I broke one of the kips valve stems so I had to fork out for four new valves from BDK at a discounted price of £160 .00.Had to take of the head again as two of them would not turn with your fingers .took them all out and completely removed on my hobby lathe the concave area above the midway “washer” so that the valves no longer touched the head gasket orifices and rotated freely.
YOU GET MORE POKES WITH TWOSTROKES !!

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500bernie
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Re: REPAIRING KIPS VALVE STEMS

Post by 500bernie »

A common problem with the replacement valves.
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Re: REPAIRING KIPS VALVE STEMS

Post by JanBros »

NOSHER wrote: Tue Feb 14, 2023 7:57 pm Oh yes Bernie when I was reassembling the engine I broke one of the kips valve stems so I had to fork out for four new valves from BDK at a discounted price of £160 .00.Had to take of the head again as two of them would not turn with your fingers .took them all out and completely removed on my hobby lathe the concave area above the midway “washer” so that the valves no longer touched the head gasket orifices and rotated freely.
you completly removed this ?

Image

shouldn't have done that, it's there to keep the valve at it's exact location, and not going up while coal and oil builts up underneath it. you should have just taken enough material from it's top so it does not touch the head anymore
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Re: REPAIRING KIPS VALVE STEMS

Post by Paul250B »

JanBros wrote: Sat Feb 18, 2023 11:31 am
NOSHER wrote: Tue Feb 14, 2023 7:57 pm Oh yes Bernie when I was reassembling the engine I broke one of the kips valve stems so I had to fork out for four new valves from BDK at a discounted price of £160 .00.Had to take of the head again as two of them would not turn with your fingers .took them all out and completely removed on my hobby lathe the concave area above the midway “washer” so that the valves no longer touched the head gasket orifices and rotated freely.
you completly removed this ?

Image

shouldn't have done that, it's there to keep the valve at it's exact location, and not going up while coal and oil builts up underneath it. you should have just taken enough material from it's top so it does not touch the head anymore
“Above the midway washer” so just the slight radius I would think
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Re: REPAIRING KIPS VALVE STEMS

Post by JanBros »

Paul250B wrote: Tue Feb 21, 2023 10:25 pm
JanBros wrote: Sat Feb 18, 2023 11:31 am
NOSHER wrote: Tue Feb 14, 2023 7:57 pm Oh yes Bernie when I was reassembling the engine I broke one of the kips valve stems so I had to fork out for four new valves from BDK at a discounted price of £160 .00.Had to take of the head again as two of them would not turn with your fingers .took them all out and completely removed on my hobby lathe the concave area above the midway “washer” so that the valves no longer touched the head gasket orifices and rotated freely.
you completly removed this ?

Image

shouldn't have done that, it's there to keep the valve at it's exact location, and not going up while coal and oil builts up underneath it. you should have just taken enough material from it's top so it does not touch the head anymore
“Above the midway washer” so just the slight radius I would think
yeah, got it now : I think he just removes the "rounded edge"
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Re: REPAIRING KIPS VALVE STEMS

Post by 350S2 »

Since plastic drinking straws are not allowed to be sold in EU (and suppose in UK as well?) there are lots of alternatives. For instance stainless steel drinking tubes. The medium size has an outside diameter of 8mm, which happens to be the same as the stems of our KIPS valves…..

I thought: let’s give it a try and bought a set for a few euros. Found a guy who machined my tortured KIPS stems down to 7,2mm and placed the stainless steel sleeves on them.

Before:

Image

Now:

Image

At the moment my bike is stil completely in parts so I can’t give you a review of this mod for some time. But thought it would be nice to share.

Greetings from The Netherlands
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