2013 - AusEx (AmEx Replica)

[exenos]

Probably snagged them from that racing kart chassis he bought a while ago.

 

[OzFab]

At the rate most projects get done around here, that a lot.

In 3 posts and like 20 pictures. It took a lot of work apperently?

Hey, you guys like pics, I give you pics

Forgive me if I blinked and missed it (working 2 jobs this week) but where did you get those freaky pedals?

Probably snagged them from that racing kart chassis he bought a while ago.

No, but they are from a racing kart. I bought them some time ago along with the steering wheel for, I think, $20.

Good to see you're keeping up ex

I cracked open the engine yesterday, more on that soon...

 

[landuse]

I cracked open the engine yesterday, more on that soon...

I thought you had done that already.....or did you just clean it?

Edit: I remember now. You just took the head of last time, right?

 

[OzFab]

Correct. I've sandblasted the entire engine & I'd previously removed the head but, this time, I stripped it down to bare block.

The first thing I had to do was file the crud off the shaft so I could remove the side cover. I got extremely lucky when I removed the side cover; the gasket remained intact on the block I then proceeded to strip the block bare...

Governor is now history! The hole in the side of the block (where the governor is mounted) was easy enough to fill; because it was such a tight fit, I simply cut down the pin that was in there & put it back in. The hole for the lever in the top was not so easy so, I tapped it out to 8mm & screwed in a M8x25mm button head bolt after applying a drop of blue loctite. A heavy soaking in degreaser to remove any remaining oil, sludge & metal filings (from tapping the hole in the top) & the inside is now pristine... except for a light honing of the steel bore.

The next thing to do was turn down the PTO shaft to fit the 3/4" clutch (sorry guys, no pics of the shaft before or during). So as not to put too much stress on my cutting tool, before I started the teardown, I formed a piece of steel to fit in the keyway, glued it in place with a smear of silicone, ground it down level & left it overnight to dry.

After turning down the shaft, I had to modify the key to get maximum contact with the shaft & slid the clutch on, only to discover the shaft was 1/2" short... Back to the lathe I go...

 

[OzFab]

Because it was there, I used what was left of the steel I used for the spring retainers, drilled the centre out to 8mm, turned 1/2" down to 19mm & an extra 3mm to 22mm. After parting off, I reversed the spacer in the chuck & countersunk the end to fit a countersunk bolt head.

Clutch done...

 

[OzFab]

One or two small updates... Time has been in short supply the last few weeks so, I haven't made great progress but, I have managed to get a few things done.

While the engine was in pieces, I thought I'd clean up the deck surface. I taped a piece of 180 grit wet & dry to a sheet of glass, added a bit fo fuel & started rubbing the block over it. A few minutes later I had a nice, even cross-hatch pattern; I'm happy with that...

I used the same grade paper to clean up the bore, it didn't do much but, as I'm not replacing the rings, I didn't really want it to. After cleaning the small amount of carbon off the piston I proceeded to put everything back together, torqueing everything up as I went.

Bottom end done...

 

[OzFab]

Moving right along, I thought it was time to make the engine mount.

I could've just welded some square tube or angle between the rear bar & the seat bar but, that's too easy & boring. Besides, the engine would have to sit back too far to clear the seat. The alternative: Sunken bars!

I started off with some 20mm SHS &, after performing some slightly confusing math, I made two V cut in two lengths, rounded the ends to fit around the round tube & put them in position. A few tacks & the engine will now sit almost 3" below the top of the frame, which also means it can sit 3" further forward & my COG is lower.

Coincidently, the 1/4" offcut I had leftover from my bench build just happened to be the exact size I needed for an engine mounting plate

After marking out & centrepunching in the appropriate positions, I started drilling until all holes were 9mm. then I ran the air hacksaw through them &, finally, filed the edges down to create 4 2" long holes.

I bolted the clutch to the shaft, bolted the block to the plate, positioned it, put the chain on for alignment, took a few measurements & tacked the plate in place. After removing the block, I proceeded to weld the plate down.

Engine mount done...

 

[OzFab]

Twin post!

So, does everyone remember what those engines looked like when I got them? Here's what the 160 looks like now:

 

[Doc Sprocket]

Nice! I'm assuming you media-blasted it, right? What'd you use? Sand, soda, something else?

 

[OzFab]

I started by removing what I safely could with a chisel, then hit it with huge grain sand (no, literally, sand) followed by a fine grade sand to give it a bit of lustre

 

[Fast Eddie]

Great job bro...your fab work is 1st rate. You can tell you've planned and thought out this build. Too bad we couldn't just ship you an AmEx frame but I know the shipping cost would be huge.

Valvesprings will work perfect by the way.

 

[OzFab]

Eddie, Just so you know, it was your AmEx that made me want one (http://www.diygokarts.com/vb/showpost.php?p=215197&postcount=3) so, thanks for the praise, the compliments &, above all, the inspiration to build it.

I probably could've had a frame shipped over (it probably wouldn't have cost much more than what I paid to have the frame bent up) but, where's the fun in that?

 

[MZ 500]

nice work on the motor where was it at the bottom of a lake?

 

[Fast Eddie]

Eddie, Just so you know, it was your AmEx that made me want one (http://www.diygokarts.com/vb/showpost.php?p=215197&postcount=3) so, thanks for the praise, the compliments &, above all, the inspiration to build it.

I probably could've had a frame shipped over (it probably wouldn't have cost much more than what I paid to have the frame bent up) but, where's the fun in that?

Thanks bro...I appreciate it. You're doing a great job. Glad I could inspire you. And yes, it is fun fabbin' from scratch!

 

[OzFab]

nice work on the motor where was it at the bottom of a lake?

Dude, keep up Read this

 

[exenos]

I think you should just put it in your sig "My motor was from a concrete mixer" Save you alot of questions

 

[OzFab]

I think you should just put it in your sig "My motor was from a concrete mixer" Save you alot of questions

...but, it wasn't, it was on a compactor...

Anyhoo...

I jumped the gun a bit yesterday: I had to source some brakes & a chain tensioner roller so, while I was there, I got an air filter too. The smallest they had was 35mm so, now I have to come up with an adaptor to make it fit the stock carb. Around the corner (literally) to the steel merchant where I picked up a 50mm length of 65mm aluminium round bar.

Back home, after a few measurements, I whipped up a design that both worked & looked half decent, then I spent the next few hours on the lathe.

After I had the shape & size right, I then used the original gasket to mark out the base, drilled the holes, cut off the excess with a hacksaw, a few minutes of filing &:

 

[exenos]

Ehh, close enough. A compactor is one of those spinning things right?

 

[OzFab]

No, One of these:

Still, it doesn't explain how it got covered in concrete...

 

[exenos]

Ah, I thought it was one of these