Finding a nice expansion chamber in Australia



Hi, I'm looking for an expansion chamber for my 49cc china kit. At the moment I have the eBay banana pipe but I'm looking for something more for a decent price available in Australia.

Side note, I have done a few things to my bike and am in the process of doing more. I have done the; Banana pipe, sanded down the stock slant head, new air filter, NGK B6HS plug, 36T sprocket, and a re-jet to 0.65 on a speed carb. I am also in the process of putting on a reed valve (Adapting 40mm OZ onto a 32mm intake with an adapter made on a lathe and mill and also windowing the piston.).
(My current top speed on a flat is 52KPH)

Thanks in advance


Active Member
May 20, 2017
Hi Dan,
I have the CDH66 expansion pipe available
I haven't put them on ebay yet but feel free to PM me


Well-Known Member
May 17, 2010
i assume you are anywhere but NSW.

you can buy my old pipe for $150 plus postage... theyre useless to me ever since they got banned.

probably have to chop it in half to fit in a box... meaning i hope you can get it rewelded... or i modify it to clamp back together for a small fee.

mounting bracket for the cylinder head (you gotta supply your own extended nut from bunnings)

spring mount header.

these were custom built for the 48's with stock standard porting. from memory i based them on 8000rpm.

used to hold 60-70km, never bothered with any of the other silly stuff, as youll find out if you go read my threads. waste of time, once you use a decent pipe.

that picture is with the experimental "duel chamber" reversion cone from twostrokewizard5... i think i threw it out eventually, though it may be in one of my buckets of scrap. so it has the normal, slightly shorter cone. if i find it, you get both cones to play with.

initial template... none of this cheap chinese bling. these were made to actually work with the engine. better to see one get used again rather than rust away in the shed. was a lot of work.

wow...four years has gone by quick...