Expansion Chamber
- Thread starter misteright1_99
- Start date
Bringing this one back from the dead....
If anyone's interested I've found another piece of software for designing expansion chambers. Says it works for motors 30cc's and up. Only problem is it costs $40
Just an FYI.
2 Stroke Wizard Expansion Chamber Design - info
I'm also curious if anyone has done the required measurements for these design programs on their 70cc HT motor...
If anyone's interested I've found another piece of software for designing expansion chambers. Says it works for motors 30cc's and up. Only problem is it costs $40
Just an FYI.
2 Stroke Wizard Expansion Chamber Design - info
I'm also curious if anyone has done the required measurements for these design programs on their 70cc HT motor...
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When I built my expansion chamber i tore my engine down and measured all the ports and the angles they were open at. I can't find the measurements now though. If I ever do it again I will post it up here.
I used this to design my expansion chamber
JavaPipe: Tuned Pipe Designer
It looks like crap but works pretty well
I used this to design my expansion chamber
JavaPipe: Tuned Pipe Designer
It looks like crap but works pretty well
erv here i would like to order a pipe for my mb any luck with chinese scooter parts 190-19 looks like it might work i have a 66cc any ideas i would like a down under the frame type pipe thanks erv
1092mm long? Good thing I have a long frame On the bike I was thinking about this for! Is the long taper to the front or the rear? I assume the assembly shown includes the header pipe or it would be even longer! And then a stinger on the end to add even more length. May have to tie a red flag on the end!
That pipe looks good and fits your bike nice. Got me thinking more about fabbing my own. Picked a piece of scrap 2 1/2" exhaust pipe at work to make the expansion part. The fun part is going to make it fit my bike so it clears everything and is still functional.
I have two bikes built. Both Schwinn Jag. I tried to upload pics but upload failed. Need to figure that out too! At least I have lots of room to work with on the Stiletto.
Should have the freewheel and sprocket I need next week and the custom aluminum Motor mount is in the works.
I have two bikes built. Both Schwinn Jag. I tried to upload pics but upload failed. Need to figure that out too! At least I have lots of room to work with on the Stiletto. Should have the freewheel and sprocket I need next week and the custom aluminum Motor mount is in the works.
What kind of pipe do you suggest for the header pipe? 3/4"diameter steel conduit? Should be able to bend that and weld to chamber.
Kind of a step by step and where to get.
The thickness of the metal is important because it effects the resonance of the pipe and gives that distinctive "ping". Mild steel that is the right thickness tends to crack so... Might want to look up what size to use based on cc's
figure the radius's of the ends of the chamber your making, trapazoid with inside and out side radius's, lay out on a piece of heavy paper ck for fit then first then transfer to steel, roll around an appropriate diameter pipe using a soft face dead blow hammer or better yet use a roll former / ring roller. chamber by chamber.
tack, then weld SLOWLY, tig preferred.
to start for the "bends" in the pipe just angle cut as you get more advanced you can do "pie" sections to do bends.
Make your silencers from aluminum, much quieter and easy to make, roll a tube out of sheet and pop rivet the seam. Swiss cheese a right size steel tube cut and weld a fender washer to the tube and add 4 or more "tabs" to rivet too and your ready to pack and assemble.
There was a company called Aircone that made pre-made cones and u-bends dont know if they are still around. Do a google search for ubends to create your head pipes from. You really have to watch the head pipe length!! don't make it too long.
Made a few, years ago, its a learning curve no doubt!
sorry for being so long winded.
bmc_az
The thickness of the metal is important because it effects the resonance of the pipe and gives that distinctive "ping". Mild steel that is the right thickness tends to crack so... Might want to look up what size to use based on cc's
figure the radius's of the ends of the chamber your making, trapazoid with inside and out side radius's, lay out on a piece of heavy paper ck for fit then first then transfer to steel, roll around an appropriate diameter pipe using a soft face dead blow hammer or better yet use a roll former / ring roller. chamber by chamber.
tack, then weld SLOWLY, tig preferred.
to start for the "bends" in the pipe just angle cut as you get more advanced you can do "pie" sections to do bends.
Make your silencers from aluminum, much quieter and easy to make, roll a tube out of sheet and pop rivet the seam. Swiss cheese a right size steel tube cut and weld a fender washer to the tube and add 4 or more "tabs" to rivet too and your ready to pack and assemble.
There was a company called Aircone that made pre-made cones and u-bends dont know if they are still around. Do a google search for ubends to create your head pipes from. You really have to watch the head pipe length!! don't make it too long.
Made a few, years ago, its a learning curve no doubt!
sorry for being so long winded.
bmc_az
Thanx for the info. Very helpful. Saw a small slip roller at Harbor Freight the other day that might work for this. Tomorrow should be a nice day to put on the big saddle bags and go shopping for supplies.
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does anone know if the type of expansion chamber OP used is still available? i looked on ebay but i couldn't find any for pocket bikes or 50/66ccs.
Try Google Product Search with the keywords: pocket bike pipe.
For some reason many vendors don't use the term "expansion chamber" and that may be why yer havin' so few results *shrug* But - be aware that 'Google Product Search' isn't a true search engine in that it doesn't search the internet - merchants need submit product lists to be included, including ebay items. So - there's plenty more out there than even 'Product Search' will return
For some reason many vendors don't use the term "expansion chamber" and that may be why yer havin' so few results *shrug* But - be aware that 'Google Product Search' isn't a true search engine in that it doesn't search the internet - merchants need submit product lists to be included, including ebay items. So - there's plenty more out there than even 'Product Search' will return
