KR-1S.co.uk Forum

morning all,up on assembly of top end,each time i nip head bolts down to the point where there slightly tight but not proper tight it seems the valves well most of them go tight ?i tried this a few time now swip swoping stuff valves ect so first i cleaned all parts with petrol there was a lot of crap where the nipple on the valves seat from the barrels being in storage for 8 year!you can now clearly see there clean n i was putting it back togeather thinking year you bast i no this is the problemo but nay lol swore at it again then tried the copper grease n two stroke oil,wd 40 tricks but nay valves are new f3 frm charles well 2 of em im using 2 standard ones in the middle because they dont line up right with all 4 in i then thought head warp but would it not make it even tighter if skimmed?i just want to hear wat i heard wen i got the bike 4year ago bzzz bzzz wen ignition on used to luv it i thougt sod it stick all four f3 valves in n lock wire em but really dont want to have spent all that doe on barrels n kips not use them loverley pulleys?any help will be much appreciated today is my day of n the sun is out so im having another go but first im going shop to get a rule to check head

only use genuine head and base gaskets. [is the head gasket the right way
round
also. loosen the eight base nuts [so the barrels are floating and not
tightened down, and then tighten the head down on to the valves. and
lastly tighten the eight base nuts.
i bet all the powervalves will then be ok

pattern gaskgets are upside down, ignore the 'up' mark.
My valves were also tight due to cylinders of different height.
I also 'skimmed' the top of the valve where it was touching the gasket and assmbled with liberal amounts of grease (in the powervalve holes).
Also found, if you don't use it for a long time, they also get stiff.

hi martin/scooble thanks for the feed back, yep genuine gaskets and right way with the up up allthough i didnt leave the barrels floating!off to the shed n ill be back fingers crossed [-o<

iberal wtf does that mean alot i was in sen 6 at english mate im doing the head gasket dry bit of grease on base gaskets ,reason being is incase i have to strip back n if it leaks ill use some bond,i was thinking of doing valves but dint want to tamper untill its last option but its getting that way,ill be back

dandan0162 wrote:thought head warp but would it not make it even tighter if skimmed?

Nope, it wont change it at all. If you were to skim the top of the barrels then you may have issue, but since the head is a flat surface in that area the only things a head skim will change is your squish clearance, and combustion chamber volume.

with the head off and the barrels bolted down,check with a straight edge if they are sitting at the same height,sometimes you can be unlucky and end up with 2 different length barrels.
If they are then you have 2 options,
Use gasket material at whatever thickness needed to adjust the heights so there the same
Or get both barrels skimmed together.
One thing you may find is once skimmed the valve will need shortening to prevent it rubbing the head gasket.
not shorten in overall length,just make the section uppermost thinner.
You can do this with a file if you have patience or get them machined down.
The section that sits just under the gasket,are the F3 and the stock ones the same thickness?
Also im pretthy sure S and B2 valves are different in this area aswell as having different size windows.
If everythings as it should be then just a smear of 2stroke oil is enough when fitting,they shouldnt be tight and need lubing to allow them to move,you should be able to turn them freely dry.
HTH

Thanks,iv took all into acount and still no joy,Dave u are right about the b2 valve having a thinner disk part I compaired it but I'm using 1s in middle and f3 on outers just because I read on here that's a good thing to do due to them not lineing rite?but onot got that far yet lol I have found ouwith no head gasket all is perfect, do I need to do thinnen the disk part then the barrels seem spot on so does head but did other people have this and does the nipple on the valve touch ?

Due to the variations in one engine to another on the KR (i.e poor quality control) you may find that even if nobody else has had the same problem it doesnt mean much.
with the head and genuine gasket bolted down there should be a small amount of vertical movement on the valve (around a mm or so),if theres not then you need to thin the coller/disc down.
Maybe try dry assembling the head while checking the problem valve,as you tighten the bolts up does it get to a point where there is no vertical play?
ive never used the F3 valves but there benefit is that they are not as fussy about lining up with port when it opens due to having the inner (exhaust port duct) cut away.One problem ive heard some mention is they dont align up with the boost chambers when closed due to the cutout.Not something to worry about on a racebike as you wouldnt be below 8000rpm very often if at all,but a pain on a roadbike.

Cheers Dave I no what you mean about poor quallity control ass at first I thought my bazers was different height but it was just the casting at bottem,tops was level I'm going to thinnen the valves and see if that works I have a few broken ones i can experiment with and Dave mine is a road bike so don't want it boggy so that's why I thought use kr1s in middle and f3s on outer I seen on a pic on here somewhere of the original kits and that's how they used to do them back to shed

Good luck let us know how it goes.
Thinking out loud,if the F3 valves are fitted on the outside of each barrel,these are the ones that do the job of lengthening the exhuast pulse so giving better low/mid range,the inners dont connect to anything they just get blocked off below 8000rpm and limit ehxuast port area.
So the inner section is missing on the F3,when they lign up with the boost chamber on the outer valves they are still going to be OPEN to the exhaust duct even though they have shut off the small exhaust port,so some of the gases can be lost into the exhuast before they have entered the boost chamber. .
It seems if im right from the above that F3 valves arent a good idea on a roadbike.
I dont know how much effect of the above would be noticeable,but the KIPS makes a huge difference in its closed and open positions,if you have ever been on one where they were stuck in either ON/OFF or not assembled or ligned up properly you will know what i mean.

Dave : I've made new links pulley's so I can fit 4 F3 valves that work in the right way, and it's working great, engine feels very strong.

can't directly compare though, as my KR was dead for more than a year and when putted back together I tuned the entire engine. still, it feels as strong as my previous engine that was done bye a dutch tuner and was supposed to be arround 70BHP (which I thinck it made since I needed stronger clutch springs).

link to my pulley's/linkages :
viewtopic.php?t=7690&postdays=0&postorder=asc&start=15

Sorted the problem kips all working nice but if they right I have no idea?they seem ok but ill look ay that tomorrow and see where they are all at on open and closed iv been running kr1svfor 3 year and first year the kips worked right after that they was Willy nilly up to about a month ago so I will no its going to be better but I do think they will need a bit of ajustment Maby but I'm curious anyhow it was loverley to hear that kips again after 2 year lol at first it did nothing I swaped cdi weren't that I then got the wd 40ut(willko brand)then wala! have you any links Jan I im having a look now thanks all