KR-1S.co.uk Forum

Is it acceptable to remove the head and barrels on a KR1S as a complete one piece assembly by just removing the barrels to case nuts 8 off and lift off ? leaving the head bolts torqued up ?
Then can they be just bolted back on with new base gaskets to avoid changing or disturbing the head gasket and kips valves ?

Is this a normal procedure if i just want to change pistons/rings ?

Do you see any problems with this ?

I previously used blue hylomar coated to both sides of the base gaskets - this gave a good seal but on removal of barrels/head assembly the base gaskets broke up and were difficult to remove fom the mating surfaces.
Is there a better product i can smear on the base gaskets which gives good sealing and also makes removal easier and stops the gaskets breaking up and bonding permanently to the surfaces ?

what is the torque for the barrel to case nuts and whats the best way of torquing them down or is this not important - i was thinking of making a short 12 point ring spanner (thinned down around the ring to allow fitting) about 50mm long and welding on a 3/8" drive back end of a socket to allow a torque wrench to be used.

I would like to get some Wossner pistons are these forged or cast ? are they available in standard size ? where can i get some ?

THANKS

i have used a v. thin coating of grease for base gaskets in the past and this has been a sucsess, esp if the top end is likely to need removing in the near future. im sure elf mentioned a good product in a fairly recent thread but have forgot what he put. its a common thing to remove the kr head/barrels as a unit without disturbing the head bolts/gasket as the kr head is quite prone to warpage if the bolts arent torqued down very carefully. i think the wossner pistons are forged? wakisaki uses them. the spanner idea is a good one. just beware of the spanner losing strength, use a quality ring spanner and modify if neccessery, may not stay nice/new but will be more use than a pristine quality one and a broken modded cheaper one.

Hi Nick,

NOS EXUP wrote: I would like to get some Wossner pistons are these forged or cast ?

they are forged.

NOS EXUP wrote: are they available in standard size ?

yes, plus one oversize.

NOS EXUP wrote: where can i get some ?

AFAIK you can order them directly from:

http://www.woessner-kolben.de/english/indexenglish.html

cheers,
Charles

NOS EXUP wrote:Is it acceptable to remove the head and barrels on a KR1S as a complete one piece assembly by just removing the barrels to case nuts 8 off and lift off ? leaving the head bolts torqued up ?
Then can they be just bolted back on with new base gaskets to avoid changing or disturbing the head gasket and kips valves ?

Is this a normal procedure if i just want to change pistons/rings ?

Yes it'll save you having to buy a new head gasket.

I previously used blue hylomar coated to both sides of the base gaskets - this gave a good seal but on removal of barrels/head assembly the base gaskets broke up and were difficult to remove fom the mating surfaces.
Is there a better product i can smear on the base gaskets which gives good sealing and also makes removal easier and stops the gaskets breaking up and bonding permanently to the surfaces ?

I use Wellseal. Its great but you need to wear gloves and don't breath in the vapor. coat both sides of the gasket and the cases and bases of thde cylinder and allow the stuff to dry before assembling.

what is the torque for the barrel to case nuts and whats the best way of torquing them down or is this not important - i was thinking of making a short 12 point ring spanner (thinned down around the ring to allow fitting) about 50mm long and welding on a 3/8" drive back end of a socket to allow a torque wrench to be used.

I've never been able to get a torque whench onto those nuts so I've always just tighten them by hand. just nip one nut up then do the opposite nut and slowly go around the cylinders tightening each nut a little in turn then repeat the sequence until tight. Tighen them in this sort of pattern IYSWIM

1746
5382

Thanks

went looking for some WOSSNER WOESSNER pics
http://translate.google.com/translate?h ... D20&anno=2


part 8043DA (std)
part 8043D050 (+.5 o.s.)


THEY LOOK PRETTY BEEFY FROM BELOW

KWAKA ONES ARE ABOUT 142 GRAMS each WITHOUT RINGS
HOW MUCH DO THESE WEIGHT???

perhaps someone can enlighten us whether theyre still running them (BANG?)

Tecnium is another or new name for Wossner. 8043DA is a Wossner part number for the KR-1 piston.

I just got a set of Wossners for my KR1S. They are 134g for the pistons (no rings) and 40g for the pins.

In the UK, Wossner pistons etc can be bought from Off Road Only ( http://www.oro2u.com )

Superbly made, and at £55 each including rings, pin and circlips, not too expensive, compared to other non OEM pistons.

I'm running a set in my TDR250 racebike, no problems so far...

just removed piston from KX125H1

appears to be a Wiseco forged 589M05600 (STD 589CS)
single ring, same wrist (top) to top edge ~21.6 (check) but flat top (dished), slightly shorter in the skirt, ring pin/gap location as per KR lower ring, 16mm gudgeon, about 7 grams lighter than stock.

now If we can only find the part number for the F3 head.

Woesnner are the best 2-stroke piston's available.

I know the guy that import's Woessner and Wiseco in Belgium, and he always recommends the Woess's

Woesnner are the best 2-stroke piston's available.

I know the guy that import's Woessner and Wiseco in Belgium, and he always recommends the Woess's

Looks like the oil holes are in the wrong place? I use a smear of grease on the base gaskets not had a problem yet