Project Ditch Salvage 2 - return to the trenches

Post by **alimorg** » Tue Jul 14, 2009 9:41 am

SHimmer45 wrote:R1-DAZ has done a CX500 conversion might be worth having a look at that for info if required

Hmm interesting concept:

Just need to chop the frame a bit!
Cheers
AL

KR-1R · Post by **KR-1R** » Tue Jul 14, 2009 8:57 pm

alimorg wrote:
SHimmer45 wrote:R1-DAZ has done a CX500 conversion might be worth having a look at that for info if required
Hmm interesting concept:

Just need to chop the frame a bit!
Cheers
AL

...HAHA

the beauty of the CX500 conversion is...
it makes more power with the ignition switched off than with the engine running.

Abel · Post by **Abel** » Tue Sep 29, 2009 1:10 pm

Okay, so since my post I've been ill, there was a plague of locusts, the dog ate my frame spars etc....
All poor excuses for slow progress, but things have moved on a little.
As you can see from below, the cradle is all tacked up. I've not finish welded it yet in case it needs to change, but after moving the motor five or six times I'm finally happy with it and will only move it if the chain run isn't right (i may change the back wheel.)

Next up is trying to find if I can fit an expansion chamber somewhere!
The radiator has been religated to the bin as it covers the exhaust port, gear linkage is looking novel as operation goes the other way to the KR1S, kickstart needs extending etc etc etc.....

SHimmer45 · Post by **SHimmer45** » Tue Sep 29, 2009 1:36 pm

alimorg wrote:
SHimmer45 wrote:R1-DAZ has done a CX500 conversion might be worth having a look at that for info if required
Hmm interesting concept:

Just need to chop the frame a bit!
Cheers
AL

Abel · Post by **Abel** » Thu Oct 22, 2009 12:59 pm

Again , progress has been slow recently, but that doesn’t mean I haven’t spent a long time in the shed – just that the rewards have been small.

Before final welding of the engine cradle I wanted to put any exhaust mounting brackets on, which meany designing the expansion chamber.
Out came the old two stoke tuning manual, a calculator and a short while later I had a sketch resembling the outline of a didgeridoo, which looked like it would suit the motor. I’m not trying to get massive power gains or anything, so I could have brought a standard one, but I don’t want it to go up and over the way it does on a dirt bike, so designing my own was the only way to go. Now I needed to decide if I could fit it somehow!

I also want to use the standard cans, so that it all looks standard when glanced at, from afar, in the dark, with your eyes shut.
To see if the thing would fit I made a wire frame like a big metal fish skeleton that I could bend around to see what routing served best, without changing the tuned length. So, I cut about 15 metres of wire out of my dad’s fence and bent up a load of circles, which resembled the diameter the chamber required every 50mm of length. I then tacked them all along their centres to a straight piece of wire of the correct tuned length. A load of bending of the whole thing later and I had my routing as you can see below.

Happy with the shape, I tacked a load of little bits of wire in between the hoops to make it all stiff.
It looks nasty because it’s just a mock-up and it was galvanised wire (hmm, ..nice smell…..), but remember it wasn’t supposed to look pretty, it’s just to see if the chamber can fit, which it can. 15mm clearance on the front tyre with the fork springs out, and the peg will still touch down first in left handers.

All I’ve got to do now is make a real one! Oh, and catch my dad’s lost llama!

pablo · Post by **pablo** » Thu Oct 22, 2009 5:41 pm

Ingenious solution =D> it reminds me of an Anthony Gormley sculpture aswell tho.Hope you're dads not to upset about the missing livestock

JanBros · Post by **JanBros** » Thu Oct 22, 2009 7:16 pm

Abel wrote:I could have brought a standard one, but I don’t want it to go up and over the way it does on a dirt bike, so designing my own was the only way to go.

I don't like that either, but I'm just gonna cut the original (well not original, I've got a SPES ) in pieces, twist them so it'll fit and weld them back together.

Abel wrote: 15mm clearance on the front tyre with the fork springs out, and the peg will still touch down first in left handers.

15mm won't be enough. Don't forget forks bend under heavy braking, and much more than you would believe

I once informed about that (when I was installing the SV engine in the KR), and I don't know the excact figure, but I thinck they recommende me to have a clearance off at least 3cm

Abel · Post by **Abel** » Fri Oct 23, 2009 1:02 pm

Good point Jan – I must admit that I hadn’t even considered that the forks would bend, but you are of course correct, they must flex a bit – the question is how much?

I’ve got an idea – How hard can you decelerate?. Can’t be more than 1g can it? – that would be 60 mph to zero in 2.7 seconds. Okay, I think I read somewhere that you can get a bit better than that. Let’s say 1.2g

What about jamming the front brake on , and tipping the bike up so it’s vertical, putting a load of weight on it to mimic me riding it (or I’ll stand on the headstock). This will show how much they flex under 1g. Assume it’s bending in a linear fashion so multiply it by 1.2 to get the most they’ll flex before you get launched over the bars or the front wheel locks up. Very scientific.
Tyre may get a bit bigger at speed as well.

JanBros · Post by **JanBros** » Fri Oct 23, 2009 5:10 pm

flex depends on the forks. the bigger zzr600 engine in my zxr400 also had that problem - front wheel just hitting the oil cooler. movd the oilcooler and problem was solved.

but then I fitted ZX6 '04 forks, and now the wheel was hitting the water cooler

ok : the radial calipers ment that I could brake harder and may cause the forks to bend more, but if you compare the weight and thickness of the ZX6 forks to the original ZXR forks, you now immediatly the the ZXR's are much stiffer.

and in general : USD forks are stiffer and withstand bending under braking better, cause the forces are carried by 2 tubes (inner and outer fork leg), compared to a "right way up" where most off the forces come on the inner leg solely.

so you might consider swapping to ZXR forkes

JanBros · Post by **JanBros** » Fri Oct 23, 2009 5:22 pm

just had a look at my ZXR600 : I'm guessing I have about 4cm clearance, and I know there's not much off that left under heavy braking, so I'd say you go for 4cm to

THE FLUTE · Post by **THE FLUTE** » Fri Oct 23, 2009 5:40 pm

My R6 race bike has 35mm gap to body work and I have a black mark on the bottom of the belly pan where the front wheel has rubbed against it!!

Abel · Post by **Abel** » Thu Oct 29, 2009 2:45 pm

Okay you miserable lot - you've messed up all my plans now! The proposed expansion chmaber has bitten the dust - it's going to have to go somewhere else.
The radiator or radiators where looking like a problem anyway, but the final nail in the coffin was trying to fit the bodywork, and the bellypan would need a "power bulge".
My body work is all cheap/ damaged/ badly bodged race fibreglass anyway so I need some new stuff and this got me thinking. Sod the idea of keeping it looking standard, what about something differnet.
I've been mulling it over and has anybody seen, or got any thoughts on rvf400 body work on a KR1S chassis? My only reservation is the tail section may look a little bulbous on a skinny two stroke with 150 section tyre. Also the tail piece may hang out too far beyond the rear wheel and cans?
Tyga do the whole lot including scren for under £300. Whoever did that photoshop CX/kr1s mightlike to do a KR1s/RVF400 to show us if it's a good idea or not.

Post by **alimorg** » Thu Oct 29, 2009 4:41 pm

The problem with photoshop mock ups is that you can shrink/expand fairings and seat pods to make them fit! to do a proper fairing swap you would need pictures of the bikes that you knew were exactly to scale & taken at exactly the same angle! Best best bet is to buy real scrap panels & chop them up!
Cheers
AL

mgtkr1 · Post by **mgtkr1** » Thu Oct 29, 2009 8:31 pm

the rvf stuff would prob look nice but a bit too much like a different make bike to the untrained eye. to spotty clueless moped brigade, it may be mistaken for a nc35!!! nsr bodywork ;looks lovely btw although my all time fave is either tz250 or hona rs bodywork. ade;s bike looks like it belongs on a 250gp grid!! i have opted for tz250s bodywork which looks lovely with a late 80's period gp250 look. i also have carbon fibre bopdywork of the bespoke kid that looks nice depending on the seat thats used (ade's seat unit would match it very nicely-rs125 h***a). you need to get the riht match between seat and fairing though for t to look right. scoobles bike also demonstrates this ethic well as does the elfs.

Abel · Post by **Abel** » Fri Feb 26, 2010 2:13 pm

Oh the shame of it all. Jan’s relentless progress, and Performance Bike magazine getting their CR500 engined Mito running this month has given me a real kick in the ass. Plus constant jibes from my biking buddies at work – I really must make some progress. But I finally finished all the booze left over from Christmas so have started to slink back into a freezing shed after lights out armed only with a fan heater and a woolly hat.

The whole project was being held up by the expansion chamber, which I managed to put off for another couple of months by doing a lot “thinking about it” and by making more cardboard models. Just to give an idea of the problem I face look at the size of this. And that’s without the stinger and can!

I finally decided to get a standard one and chop it up, so ordered this an some other bits off a very helpful motocross breaker up north.
What I received was a box of mud, but on further inspection each sod contained a component.
Imagine my surprise when I chipped away at the biggest one to find this gold series FMF fatty!

Sadly it’s chromed and the first bend again gets too close to the front wheel on full bump. The chrome could come off, but even cutting a re-welding (in a similar configuration to what Jan has done) would mean that I couldn’t fit the fairing back on without chopping a big hole it in – which is not the look I’m after.

I found a further stash of beer and some far more important things to do instead, like coil and CDI bracket, front sprocket cover etc, pretending the expansion chamber would sort itself.

Unfortunately it didn’t sort itself, so after another few iterations of wire frame and cardboard models I was left with the final design - which is this.

Because the engine was offset slightly to get the chain run correct, and because there’s only a tiny water pump not a huge generator on the right side, it means there’s more space over this side. I think I might even be able to fit a fairing!

The level of procrastination was getting embarrassing so finally metal started to be cut.
Bar turned into this,

Which has turned into this – the first bend.

130mm done – only 1250 to go!

Jan – I’m glad to see that you’ve gone for 2 silencers. I hope it works. The reason for this is that I want to keep mine looking standard, so I intend to have two stingers running off the end of the convergent cone, The internal bore of the KX stinger is 30mm. This would look wrong as the o/d would be about 33mm. Two standard KR1-s stingers would do the job, and as they are slightly longer than required their slightly larger than the ideal 21.2mm bore would be fine.
I don’t want to chop my KRI-1 expansion chambers as they’re in fairly good nick. I don’t mind unbolting the cans of course. Has anyone got some really manky expansion chambers that are beyond repair? If so cut the stingers off and I’ll buy them off you.