expansion pipe

[metaljoiner]

I have now practically finished my exhaust pipe, tried to Tig them up, but just too much messing about, didn't get on with the Tig at all, don't know if it was cause it was a cheap Tig machine, I just don't know! Well I went back to Oxy Acetylene welding' no trouble at all, welded up lovely! it felt good after the hassle with the Tig, recon if you got a half decant oxy Acetylene set, you don't need anything else.

 

[gavuk]

Good job,what are the exhausts fitted to?did you copy available exhausts or design from scratch and i assume you bought the downpipe ?,my lad is struggling to get an exhaust for his early aprillia rs50,i have thought of copying an "arrow"exhaust but am fascinated with the science of back pressure,gas flow and noise but its very easy to get bogged down with the science.......cheers Gav

 

[metaljoiner]

This exhaust is for a 83 Suzuki GP125, I am building a Bucket Racer, the down pipe is from the original exhaust, could of made one up, but the bore size is the same, so I cut it off and welded it to the expansion pipe you see in the picture, I have a program that works it all out http://www.buildandclick.com/ But saying this, it is true you can get bogged down with it, but really unless you are building a full blown racer you don't need to be perfect with the dimensions, you look at all these so called expansion pipes these teenagers got on their bikes lots of different models but all the same size exhaust pipes, and they do up the power of the bike.
The bucket racers in new zealand use SUZUKI RG500 pipes on there GP125s

 

[Robotstar5]

Nice welds, I had a few 2 strokes in my youth, makes me smile when kids remove baffles, sounds faster but actually reduces performance.
I wish my wife would let me weld on the kitchen worktops!

 

[metaljoiner]

My wife didn't know I put the exhaust on the work top while I took photos, she would of slung the exhaust and me out the back yard

 

[gavuk]

Now your talking gp 125,,,remember my mates putting microns and allspeeds on theirs ,i was still on my ty50 then with a fresco exhaust,then the rd 125lc came out and was the road racers favourite for a while.......previous owner has removed the baffles from boys bike and he wants it quieter?......i think hes changed his mind about fitting new exhaust bigger carb reeds etc cos of the cost ,we'll wait and see tho ,i draw the line at big bore kits tho.......Gav

 

[metaljoiner]

I originally bought the bike to get me to work, save on fuel cost, but don't need to now, so I thought I would turn it into a little racer like in the photo. give it run around the local race circuit, Ive done a few mods to the engine also, It should go quite well, don't know how long it will last though.

 

[gavuk]

What have you done ?reeds,2bottom gaskets ,silver foil head gasket?file match the ports ,upjetted the carb and changed the plug (what i did to my ty)........