KR-1S.co.uk Forum

hi all not been a member for long but have seen some really good projects on here and fancy fitting some zxr 400 forks to my kr1s as mine need re chroming. do i need the top and bottom yoke as well or can i use the kr ones also can i still use the kr front wheel and are the brake callipers a straight fit.

You will need either zxr250 or 400 yokes, 400h and l are different, the l series has a much thicker (than the kr) stem. Also l series legs will not fit h yokes without slight modification (bottom yoke needs opening out by 2mm)

zxr250 yokes have a slightly narrower spacing so lend themselves to using the kr wheel as it is narrower than the 400. In fact a zxr250 front end can be made to fit straight in with a custom castle nut on the stem, or a stem swap. The only drawback with this is you lose the 1s 4 piston caliper brakes for the kr1 2 potters, discs are similar if not the same (1s size)

400h yokes can be made fit with spacers but a stem swap is better, 400h legs in good nick are not always easy to find, and as you know re chroming aint cheap. zxr400h discs and caliupers are the same as a kr1s so you can reuse them if you want or fit even better calipers, fireblade, zzr1200 gixxer600/750 etc.

Really does depend on what you want to do, with the zxr parts you can pretty much sort it all out you may need some custom spacers but in the main they should be easy to sort out. I'm currently seeing about sorting out some front wheel spindles to fit 400l forks but to use the kr1s wheel.

Whatever you get someone will be able to point you in the right direction, if I can do it anyone can

i use nigel at nk racing for my engineering needs he did the stem swap on my nsr (fitted rvf 400 forks) for £35 and under slung caliper bracket and few other bits and hes always done a fantastic job

correct me if im wrong please. i could use the 400h yokes but i would need spacers. but a stem swap is better could you elaborate on this.

if you get the 400 forks and yokes all you need to do is put the stem from your kr1s and then put it in the zxr yokes its quite straightforward for the experts you just break the welds on the yoke and they slip out i think thats the best way of describing it mate

yep i see the light now thanks.
so with wanting to keep the 1s calipers 400h forks and yoke with the stem swaped. so what wheel can i use?

any Kwak wheel, like ZXR400/750, ZX6/7/9, ZZR600/1100, ...

almost every Kwak wheel from the '90's

Easiest is to get a full front end, probably zxr400h, you should be able to get one for around £200-£250.

Get the stem swapped, NK racing will do it or you might be able to get it done locally, you will need acces to a press though.

Sell of which bits you don't need (extra discs calipers, kr mudguard etc)

Be aware that you will need to modify your lock stops or your clutch lever will clout your fairing bracket.

So...... thayt's your front end in, but now you've got a mismatched wheel zxr400 3 spoke on the front.....1s 5 spoke on the rear.

Answer stick in an rgv rear.

If you want to keep the 5 soke front, you will need to get some spacers made.

If you stick in an rgv rear you will need to get spacers made........

And get the VJ22 17" rear wheel for better tyre choice as well. Or just get a full RGV Swing arm and rear end The list goes on and on LOL

ok i will start with the 400h front end get that built and then start thinking about the 5 spoke 1s wheel route or the rgv. thanks again for all your help.

If you're after a zxr front try Baz from Leeds, he trades on ebay as secialized_zxr or something like that, he normally has about eight bikes in so may be able to help you.

also worth mentioning, if you go for ZXR400L forks, then you must also get the smaller L calipers and bigger (310mm) discs.

scooble wrote:also worth mentioning, if you go for ZXR400L forks, then you must also get the smaller L calipers

KR-1S calipers are a direct swap, you don't need the smaller L's

I did get a set of KR1S pads once (by mistake) and found that they where way too big for my calipers, so assumed that the L calipers where smaller

scooble wrote:I did get a set of KR1S pads once (by mistake) and found that they where way too big for my calipers, so assumed that the L calipers where smaller

Yep the calipers are smaller on the ZXR400L but they are a direct swap the differences is in the disc size (310mm on the zxr400L 300mm on the KR1S and ZXR400H) and the fork leg bottom which spacers the caliper out further for the bigger discs.