Expansion Chambers

This topic seems to come up fairly regularly, and with a poor choice of 'off the shelf' pipes that actually work, I've been working on a few different Pipes and believe this is where the latent power is lying in a two stroke motor, My results so far have been good with the torque pipe I built for the Goat, But I'm keen to try these KTM pipes out.
I've tried to keep the KTM pipes as close to original length as possible, but had to cut an inch or so from the 'Pro pipe' to get a neat fit without it looking too 'hacked up'. On the 'Dirt Bike' the pipe will be wrapped, to avoid me burning my self, but also to limit heat transfer to the head, with so much of the pipe so closely wrapped around it. But I love the look of the tight fit and the Puch head, although a standard center fire would make access to the spark plug easier.
It would be great for others to post up some more pics of their set ups.

I'd love to see some photos of your pipe.
For low down, anything less restrictive than the standard pipe is going to help.
For mid range a long tapering header/ diffuser and a bit of belly is the trick.
The snake pipe does look to have reasonable dimension's, and it would be interesting to cut one up and reconfigure it to a more compact design, but I think it looks to be a little more top end orientated compared to the likes of a Jag Torque pipe.
My torque pipe gives great Mid range grunt, but tends to not let the motor rev out past the high 8000's, which is fine, kind of like a rev limiter.
My two KTM pipes come on a bit later, with the bigger pipe hitting max power from 8 to 9000 RPM and easily pushing past 10 000.
The Smaller KTM pipe is probably my favorite, it's not to loud, was $80 delivered with silencer, hits 10 000 RPM and gives good power all the way.
The unplated finish makes for easier touch ups after modifications and it wasn't to bad to weld.

Depends on what head your running and ambient temps.
I find angle fire heads run a little hot at over 150 deg C.
Although I'm told it's OK to go to 180 deg C.?
My straight fire heads usually run just above 130 C.
My Puch heads even less, usually staying below 130 C.
I havn't bothered with header temps as yet.
I find a pipe makes it easier to tune the carb, as you get a much more pronounced 4 stroke when rich.

I just got your photos, it looks good, probably a little short for max mid range torque, but a nice fit, and nice welds.
I believe the angle fire head works best the way you have it. Some, including my self have spun it for frame clearance. Once you start raising compression and trying to get a bit more out of these motors the angle fire tends to run too hot.
The straight fire also gives better torque.

I have two reed valved motors, one a custom made case induction with hand made 4 petal (2 pair of carbon pocket bike) reeds.
The other a 4 petal RSE,
The smaller (2 petal) RSE reed is probably a little small, but the 4 petal will need a barrel with the wider inlet stud spacing.
I'm very happy with the performance of both, although both are new builds and not yet broken in.
Both are running KTM pipes, higher compression, bigger carbs, boost ports, reworked transfer ports and huge exhaust ports.
The reeds can really improve the low and mid range to a modified motor and if big enough still allow 10 000+ RPM's and top speeds in excess of 50MPH when mated with a decent pipe.
I think your pipe would complement a decent reed well. And with a few mods to the barrel and piston, will give some awesome power, but you may want a reed to restore your lower end, if porting for those sort of revs, If your crank is balanced, I'd make the most of it. I have 3 cranks that will happily do 10 000, none of the others would, one got to 9500, just.
Doing a few mods and getting your max power at 8000 odd RPM is a lot of fun and probably netting twice the power of a standard motor. It's also likely to get you a gutless bottom end with out reeds.
If however your not concerned with top end , reeds aren't going to make a huge difference to a standard properly port timed motor, but will improve a motor that has had the inlet timing extended.
As for bigger carbs, Probably depends on the level of tune, Speed carb is fine for all but highly tuned/modified motors.
I like the adjustability of Walbro style carbs, a bit more work setting up, but heaps quicker to tune/retune.
As to how they take abuse, keep the temperature down!, keep the carb tuned right, use good quality oil, keep a spare mag!, check for loose nuts and bolts and give'm a good thrashing, they're cheap fun, parts are cheap, they are easy to rebuild, fun to modify and scary fast if you do the right mods.
I have 4 bikes, two highly modified, 2 more mildly modded, even the mildly modded ones are probably quite a bit faster than a standard angle fire motor, and will do 40MPH+
Without sacrificing low down, so for most people, this is likely enough. It's not to hard to do with simple porting, getting compression right, a better exhaust helps and the standard carb is totally adequate.
Starting with a good bottom end is probably the most important thing influencing the reliability of a 'tuned' motor.
And I wouldn't trust it out of the box from China.
Investing in a 40mm stroke bottom end, stripping it, checking it over properly and building the motor from scratch is the best way to get a reliable engine, others have obviously had better luck than me, but the only motor I have that did not require stripping before running is from 'Screaming Roo' and it cost twice a China Girl. But is sweet.