Puch Tecno Estoril Performance Pipe

My first order of business this spring was to install a Tecno Estoril performance pipe (de-restricted version) on to my Gila kit.  This pipe is made for "flat" type exhaust port cylinders such as the Polini kit vice "angle" ports found on Gilas or Metra kits.

More shiny = More fun?

Smoke that "cigar"

Before getting into the fit-up and installation processes, I want to share some history on why I choose this particular pipe.  I've been running a Homoet 8p "cigar" type pipe for a long time in Hawaii.  Where I lived, there were a lot of long straight-a ways with not too many hills.  The Homoet pipe was perfect for these conditions since it was primarily a top-end pipe.  In Japan on the other hand, where I live, there are a lot of hills and shorter straight-a ways.  My longest straight-a way would be from green stoplight to green stoplight.  The Homoet pipe was simply not going to cutting it for these conditions.  I needed my bike to have a wider power band particularly more low-end to mid-range power.    I tried to compensate for the lack of low-end with clutch work, jetting, and timing but with no success.  After a lot of research, I contacted a memeber from moped army to get his advice since he runs both "cigar" and "bladder" type pipes on ZA50 Gila setups.  Also, I read on a forum discussion that his riding environment was similar to mines.  He recommended the Estoril pipe as a good all condition all weather pipe.  Although, not as powerful or less top-end as some other pipes, he seemed happy with the performance of the Estoril pipe for his daily commuter:
  
"I run derestricted Estroils modded/bent for angle port on 2 of my gila za50s . Treats sells estroil all ready  derestricted now but you will still have to hack and weld or bend for angle port.  My speeds are only 55-57mph with 21x34-35 gears, 24 mikuni flatslide but no gaps at all in the powerband .  I got 2 big hills , several smaller ones my me and 50-55 mph county roads with truck traffic. I never get stalled transfers/fall out of the power band ever but less top speed and rippage then my bk100 and destroyer pipes .  Clutch life is very long with a estroil pipe and head temps are cool but again less power then a 8p, bk100 destroyer type pipes.  I got bikes with estroil, bk100 side bleed, bk100, motomatic Seattle  destroyer and techno circuit.  I pick the estroil bikes for any weather, wind, hills or traffic and all around use
The other pipes are 6-8 miles faster but are peaky and certain conditions won't go into the power like a long up hill into the wind I'm stuck at 35-40 mph.  It's like 44-45 mph when the power hits and I get low 60s mph out of the bk100, destroyer type pipes no tuck, high bars and I weigh 190 lb.  I do lose power and top speed with a estroil. It makes all around tractable power just less.  Shortening the header a few inches gets more top end speed but I never did it"

I also contacted Tomahawk Mopeds.  They recently finished a Puch Gila build and used the Estoril pipe on it.  I asked them why they choose that pipe.  They responded:

"The estoril pipe performed really well with a wider power band but still good top speed 70 mph.
Somehow the pipe works better keeping the restricted plate in the convergent cone."

I was convinced and put the order into Treats.

March Madness!!

Like I mentioned earlier, the angle of the exhaust header needed to be corrected to fit on a Gila kit:

A friend of mine made a jig using the Homoet pipe as a guide and a piece of scrap wood in order to get an accurate fit up on the angle needed for the exhaust port:

Ghetto Rig Jig

 Measure once, cut twice:

Cut off about 1.5 linear inches of the pipe.  Then an additional 1/8 linear inches!!

But a perfect fit:

Dead nuts on!!

Now to lay down some coins:

Maybe not dimes...more like 5 yen coins!!

But the finish product speaks for itself.  Cleaned up and ready to go:

Gila ready!!

Mounted:

Tecno Musik!!

Ready for testing...

Some lessons learned:

1. Make a jig.  My friend made me a jig to get the angle perfect and assist in welding.  I was initially was gonna eyeball the whole process.  At the end, the jig made it extremely easy during fit up and welding.
2. If you use a MIG to weld, it's best to preform the welding at the beginning of the header.  This is because you can easier access the welds on the inside of the pipe to smooth them out to minimize exhaust turbulence.  TIG welding of course doesn't matter since it is cleaner.
3. Be very careful not to cutting too much of the pipe at the beginning of the header.  This affects the fit near the magneto area of the motor.  Mines was a very tight fit:

Squeeze!!

Performance:

From my initial test (around the block), my bike definitely performs differently than when I had the Homoet pipe on it.  I can feel it 'will have' more low-end to mid-range power.  I say 'will have' cause its bogging at the low-end because my carb settings are all off coming from the Homeot pipe tuning.  Didn't really push the top-end yet but it seems that something is there.  Will post a video of my First Run.  More tuning and fiddling around to come but that's what two-stroking is all about.  Overall, I'm impressed with the Estoril pipe so far.