Crofter985'S KLX650C supermoto build

[Crofter985]

Ha ha, you will be basing that on it being green! HP does have the problem of the local law not being too happy about vehicle modification, or so I am told. That's why the turbo is tucked away. My setup is a more "look at me" approach.

I'm going to be lucky to finish before the summer finishes. It's not started yet but it does not last long.

[Sandblaster]

Well.... Green does equal HP

[Crofter985]

Well hello! A nice treat to come home to.....



In a box inside a box, how cool is that?

[Sandblaster]

Wow, check out that beefy bad boy!
That should take a few pounds of boost with no issues.
Nice!

[Crofter985]

Right, a while there with not much done, phisically anyway but some parts gathering and planning, lots of planning, most discarded for being daft/crazy/impossible.
I took a cylinder head, cylinder and piston to work with me to familiarise myself with the parts.

I got a bit tempted to do a big bore, that was the main reason for the hours of fondeling those castings, but Iv kind of gone off the idea, the extra time and effort and then the extra gas to go past the valves and that goes especially in the case of the exhaust valve. There will be a bit of heat there just dealing with 651cc. I already have a 100mm standard bore wossner piston as well. So, standard bore it is.
My bench is abit of a disgrace, tools and aluminium dust from the plenum build, I cleared it up a bit but I had already decided a new bench was needed, one dedicated to spanners bolts and stuff. No welding and grinding allowed. So a few bits of wood, screws and a big bottle of glue.

It might be a bit high but I always end up face into everything peering at it so the height might be ok? If you cared to look closely at it, it would betray my lack of carpentry skill but I do not expect it to fold in a hurry. It's braced in all panes by plywood and that's a 2" top, bench sorted.
So, let's get some use out of it. Here's some of the new internals, I was going to run the engine as made but the standard cast piston really would not do with the extra heat. So to solve that a forged wossner piston has been sourced, I got it about a year ago, off eBay, it's brand new but 2nd hand.

The other parts here are head and base gaskets and a full gasket set(not in pic) a new crank pin and thrust washers, a Carrillo rod, a KLX "R" inlet cam and a walkers of NZ clutch with uprated springs. Another thing I forgot to dig out for the picture is a set of viton valve stem seals.
There is also a new carb/air box adaptor there, I found it on eBay, it came from a vendor in Holland it is a more satisfactory adaptor with more sealing area than the one I had before, better for handling some pressure, hopefully.
And most obviously yet another engine. The engine is still in the bike, I got another one around Christmas and then another last week. I am sure I will wreck one do another is handy.
The last bit of this update is slightly off topic but same kind of vein, I found this little gem, again on eBay, a KR1-S 250........

The plan is to take out the little two stroke engine and shoehorn a KLX engine in it. Only after I get the turbo supermoto up and running. It's been set up for racing so there is an uprated shock and zxr400 usd forks so it's a decent base to start from.
The next move is to strip down one of those engines on the bench, to get the crank out, I'm going to order a new set of rollers for the big end, I mistakenly thought that a bearing came with the rod but I misread the email on that one, , no matter. I am going to take the crank to a specialist crank builder, to fit the rod, bearing and to weld it up to help it cope.
Then after I get the last of the intake made up I will take the engine out of the bike and strip that bike down and build it up with the assembled trick parts.
So lots to do, as usual.

[Sandblaster]

That is an amazing amount to digest and it's late.
I have a few comments I'll make this weekend.
Tall benches?
If you have to bend over to use them they are not tall enough

[Sandblaster]

If I'm considering a mod on a part I leave it on my desk for weeks to make sure I've considered all the angles

No matter how large my work benches I always clutter them up.
In fact, I'm working at redesigning all my benches right now to help with all the engine builds we are doing.
It's a job keeping everything organized and separated while waiting for parts.

I've been using Wossner pistons in all our high end builds.
So far, no failures... I think you made a great choice.

Which top end gasket set are you using?

It's always good to have another engine ready to go.
I need to get busy and get my next build going...

Viton is good stuff... highly chemical resistant, extremely heat resistant... In fact you'll probably ruin your aluminum if your engine gets hot enough to ruin the Viton.
It also works good in vacuum conditions.

I love that KR1-S 250.
If I had it I'd be trying to put a bidder 2T engine in it.
I can't wait to see how you handle that build.
Keep us in the loop.

[Crofter985]

ive spent most of the weekend tying to re-organise my workspace. In December there was a storm and it sucked the 15' wide roller door of my shed out of the tracks at the side. It wrecked a lot of the sections, it took ages to get new ones and then find time to repair it. I got that sorted the other day so a big spring clean is in order.!!!
Iv started with the side the new bench is on. I've made a set of shelves to put the tooling and drills for my lathe, there is another two sets of shelves to be made and I sawed up most of the parts for them too. I ordered a milling machine last week, iv been putting it off for a bit but there is a stack of jobs I have lined up for it now so it had to be done. The two (to be built) shelves will flank the mill and hold the tooling for it. Some of the slowness of progress has been lack of equipment and some has been the lack of space because of the bottle neck of crap in the shed due to the broken door, most has been absence(at work).
What I did get done tonight is finish a stand for the engine, just to make it easier to work on, I still have to add pins to it and drill the bench so the pins slot in to hold the engine as I undo the bolts, or tighten when re-building.

I'm going to make another that holds the crankcase on its side when splitting it.
I got the dyno roller and bearings and stuff when I was away last week, I have to go to speak to the old fella who is going to do the machining work tomorrow, just to finalise the plan for the design. I'm really looking forward to that. There is a load of things I want to do with that. The guy I bought the roller off turned out to be a really nice, interesting, mine of information, I know what PC interface hardware I'm going to order and I've spoken to the UK agent, I didn't order just there and then but I think I'm sure of what I need to get the results I want.
So no engine tear down yet.
I've also had a re-think about the water injection pump, I think it will go alongside the rear shock, I kind of intended to get a piggyback reservoir shock so discounted this idea, but it makes the installation of the pump more sound in an engineering sense so I looked around and found a shock with some adjustment but in a shock only setup, so that's a bit of a re-think. I was thinking a lot about how dependent the engine will be on the water injection, if the pump was to start struggling to get water to it the engine would be toast in seconds, i have plans for a higher compression engine for the future.
You ask about the gaskets, I have a aftermarket full set but I got two Kawasaki oem head joints and a base, so I should have enough for a dummy build and then the real deal build.
The kr1-s, I would nearly think that if the turbo is in any way successful the kr1-s will get one too.
A little interesting thing also...... Turboed engines (apparently) need better exhaust breathing, so if I were putting bigger valves in, I should go up more in exhaust size than inlet. I'm trying to find a supplier who will talk to me about valves but not having much luck. The general idea with the breathing is the intake being pressurised will take care of the "in" but the turbo is on the "out" slowing it down so a little help there is good. So what I'm thinking of doing is putting the longer duration "R" inlet cam on the exhaust.... But of course, if I build it standard first I can dyno it and then swap cams and dyno it again, I don't say this very often but, I can't wait.......

[Crofter985]

[Crofter985]

The first thing I did after the cam cover came off was to check the valve clearances, exhaust, both zero clearance, this engine must not have been running very well. Then I noticed that the little spring that holds the KACR (autodecompressor) was missing. No sign of it yet. Then I saw this repair job on the cam retainer, quite well done, somebody must have dropped it??


I'm not sure how the stainless steel inserts are held in the alloy and I would have to destroy it to find out so I will just leave it.
i took all the rest of the parts off the head and took it off. Oh yeh, when I lifted out the valve lifter buckets I found a scrap of spring for the KACR.

The inside of the combustion chamber looks kind of oily, could be leaky stem seals, the head gasket looked ok buuuuut........ Possibly no wonder, the exhaust valve seats are in poor shape, the lack of valve clearance would explain that and the engine could not have been making much power which of course is pressure, so no stress on the head joint.
Here is a little idea I had to lock the clutch.

Don't know if I needed the two but it did not slip anyway.
The clutch basket centre had two strange marks on it.

It looks a bit like welds but it's not that, certainly heat has been involved, but when? The part looks ok though, see what the rest of them looks like, I've got two more to strip so I might be wiser by that time.
Yuck!

It looks worse than it is although it's not good, it's mostly black sealant, or that's what it looks like, also some more of the KACR spring.
Here's how it should have looked.

It's not just that great but not all bad, all the bearings look good. I suspect the engine that is in the bike just now will be suffering in the exhaust valve department, it was a bit down on power I thought, it certainly shows how important regular maintenance of the valve clearances is.