KR-1S.co.uk Forum

i know alot of these bikes is essentially the same and interchangeable and i have seen alot of kr1's with kr1s, forks, brakes, wheels but what i was wondering is if i made a kr1s rolling chassis from parts, would i then be able to strip down my kr1 and build it up around the kr1s chassis?

i know theirs some small differences, such as say, the side frame fairing bracket, on the kr1 it has a step in to go with the styled frame apposed to being just flat like on the kr1s, but is their anything more major like engine spacings etc?

just a plan im joggling with in my head.

cheers

jonny

yep.

if you have a complete rolling chassis, ecerything else can be transfered.

what's no direct swap are swingarm, wheels, and front brakes, but with the nescesary changes, even they can fit.

thanks are the fast reply.

my initial changes to my bike i was thinking of was the kr1s running gear(forks, swing arm, wheels and brakes), but then i was thinking to myself my bike would then only still ever be just a kr1 and not a kr1s so why not change the frame also.

do you know if their is any differences to the engines between the two, externally they both look exactly the same, but i dont know if they have different porting, gearbox etc? if so what sort of a power difference are we talking, i know swapping the pipes on a kr1 to kr1s items is suppose to make a fair bit of difference but i cant really see them messing with the porting much if any.

cheers

jonny

The KR1S has 5hp over the KR1 (much of that comes with the improved pipes). The ports were changed a bit, most noticably being the deletion of the silly port opening half way up the rear transfer, and the KIPS ports were made larger with new valves to suit. Minor changes were made to the carbs (mainly the needle) and the CDI was revised slightly.
The gearbox is also slightly different internally, although I don't think they actually changed any ratio's at all.

jonnykr1 wrote: my initial changes to my bike i was thinking of was the kr1s running gear(forks, swing arm, wheels and brakes),
jonny

The S swing arm does not fit in a KR1 frame. (Well it is not easy to do). Forks do, wheels need different spacers to make the S wheel line up properly in a non S arm.

If you are going to the trouble of making new spacers you might as well do it to get a 17" rear wheel. Suzuki RGV are ok and you can fit the front as well to make them match.

My KR1 has RGV wheels front and rear and the VJ22 front forks and brakes as well

its sounding more and more like swapping my kr1 frame to kr1s frame is the way to go.

i wouldn't try putting usd forks on it though, a few years ago i had a vfr400 nc30 with some zxr400 usd forks fitted, made the turning circle appalling, their was just no lock at all.

thanks for the info guys, now to wait for parts to crop up cheap!

Steering lock on mine is the same pretty much as stock.

I had to modify the front subframe by flattening the tubes to get the clearance to the fork uppers, but with the gas axe out and the copper and hide on the case, it wasn't to hard....

I'm using ZXR400 triples withe the KR spindle in (I made two sleeves that are pressed into the upper and lower to resize the holes.

that sounds like it was a lot of work, my my nc30 it was just like a billet piece of alloy to extend the length of the headstock, then zxr4 yokes and stem (zxr same thickness stem as a nc30), but it still retained the nc30 front wheel, however the discs where nc30 inners with zxr400 rotors, must of has some custom wheel spacers, but i dont know as it was like that when i got it, realistically you would need a 4 lane road to do a u turn on it really was that bad!