KR-1S.co.uk Forum

Has anybody tried boring/stroking a KR1/S and putting larger capacity barrels on . Spotted this while surfing and just wondered. http://www.twostrokeshop.com/two_stroke ... ngines.htm That engine looks very tempting, wouldn't mind 112 hp .

Hi Mark,

Stan Stevens did a 300cc kit but it was a fair way off 112bhp

Cheers,
Bernie

Falconman is busy doing something like that :

viewtopic.php?t=5030&highlight=

That's a definite labour of love. Hat off to Falconman. Jan I've noticed your engine transplants (loved the SV650) , have you looked at transplanting a 350 power valve motor?

Why bother http://www.krazy-katt.com/MJsKRvTZ350.htm

Mark66 wrote: have you looked at transplanting a 350 power valve motor?

looked, thought, wished, hoped ...

just a 350 power valve would be useless as MJ says. I'm thincking more along the TSS/Banshee 500's lines, but checked my banc-account : it's a no-go for me

that's why I'm making a KR1/KX500 : enough power with less expesnsive internal parts

Mark66 wrote:That's a definite labour of love. Hat off to Falconman. Jan I've noticed your engine transplants (loved the SV650) , have you looked at transplanting a 350 power valve motor?

It's been done before. A more impressive conversion is fitting an RG500 motor and then giving it some RGV barrels. But it would probably be cheaper and easier to go the banshee 500 route.

I"m with you there Jan you have a 500 and it's all Kawasaki . TSS engine is a peach, albeit an expensive one. Definitely a Kwikasfuki if you ask me. I know they are a bit old school now like me but i wonder if an H2 could be shoehorned into the chassis? I'm sure it could be quick. possibly with grafted on modern topend. I miss the sound of my old KH400 with denco pipes. I think its was shame they never got round to building a modern 2/3/4 cylinder 500. Thanks for the input guys, I'm trying to get a handle on these bikes and the possible mods . Seems you lot have tried them all . =D> . God , I like this site . Mark

PB did an article some years ago on someone who did in fact shoe horn an RG500 engine into a KR1 chassis, it was a bit tatty, but kind of worked.
On the old forum, one of the members was building a KR1 triple, but never heard any more about it
If you want to really bonkers, its possible to get banshee triple crankcases, but for the ultimate, see this;
http://www.trickracing1.com/Twin_CR500.html

Now that's what I'm talking about. Hitting the power band on that must be a rush , brought an insane smile to my face just thinking about it. I'm glad there's still quite a few nutters out there with the balls to build motors like that. Think the swingarm may need some bracing though . That's going on my christmas list , deffo.

There is also a guy on the pbmag forum building a v twin with 2 cr500 barrels on hand machined billet cases. Read the full story here- http://pbmagforum.co.UK/index.php?showtopic=14083&st=0
Madness!
Mike

After careful consideration of the options I've come to the conclusion that increasing the capacity of the original engine has limited potential without some serious work ( Go Falconman ) . On the other hand there are any number of possible engines that can be fitted , ( Go JanBros ) and as we have seen there are some serious motors out there. That twin CR engine would be a hoot . Anyway I think I'll just stick to blueprinting/mild tuning for the moment although sticking a 500cc 2stroke single in there could be a relatively easy option. My mate has a RGV with a DR800 in it but I definitely want a stroker in mine, something just not right for me with a four stroke engine in this bike.

Go big!! 2 to 4 cyl up to 2700cc.

http://www.mattoonmachine.com/Billet_Cases.html

Or if you want it more Kawasaki,

http://www.exbilletengines.com/Tech_det ... tails.html

I have definitely been in hibernation too long, those sure are some very nicely made pieces of modern engineering .I know we are getting a wee bit off topic but it was worth it just to see what is out there if you really want to go completely overboard with a capacity increase these days. Personally it would have to be a big triple . Love the sound.


These bikes are old and it's not a great video but just turn the speakers up. just sounds so right.
. It's good to be back.

Can anyone tell me the diameter of the crankpin . I have found a possible way of stroking the standard crank by getting it spiral welded and reground . This process is used to repair and add material to all sorts of shafts including cranks so it definitely has potential, a quick search on the net will give more details . The only drawbacks I have are that the crankpin may be too small for my nearest firm to weld and the question of rebalancing the modded crank . I am going to search a bit further and report back. Anyone tried this process before? Also can anyone tell me how much of an increase in stroke the standard barrels could stand and if they can't what barrels would you suggest as a replacement. Not asking much, am I?