$25 expansion chamber works great!

[Ghost0]

That is true but usually not in the 7/8" ID that we need. They are usually in the 1/2" range. Here is a pic of the tubing for some visual reference.

 

[dave1490]

Side and rear pics!

not a bad fit,follows the contures of the bike nicely.almost looks like a factory install.i,d paint that crome part of the old pipe black though.also the clamps.

 

[Hard rider]

That is true but usually not in the 7/8" ID that we need. They are usually in the 1/2" range. Here is a pic of the tubing for some visual reference.

Thanks for your info Ghost!

 

[hotsauce492003]

Thanks for the tips Hard Rider and Ghost.
That set up looks good on the bike.

 

[Skyliner70cc]

That is true but usually not in the 7/8" ID that we need. They are usually in the 1/2" range. Here is a pic of the tubing for some visual reference.

Sorry, but your reply to my original post was not accurate. Here is one example of a model airplane vendor that sells 7/8 ID silicone tubing.

http://www.aerotrend.com/shop_subcat.php?subcat=7

Commercial model airplane engines come in many sizes larger than 70cc.

Check out some of these beauties that range as large as 212CC 4 cylinder engines! http://cactusaviation.com/Products/Engines/Signature/signature.html

 

[Ghost0]

Ya sorry for the misinformation. Although not that "old" myself I am still stuck in my modeling days when the largest motors in the R/C industry were like 21's and 40's. I know they have some 1/4 scale cars and plains that use some 100cc motors. Sorry for this off topic but check this motor out. Would make a cool bike motor I think.
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5734

 

[hotsauce492003]

What exhaust chamber works best on a twin cil.engine?

Ghost that's a nice engine.
Now imagine that engine on this bike: http://www.hawkclassic.com/#
on the chainless driveshaft transmission Hawk ACE model like on a BMW bike.
The question related to this thread is: Does anyone know what would be the ideal expansion chamber on a Twin Engine performance wise? Two separate ones or a common shared one like this one comes equiped with? (The stock one looks ugly, like a VW bus muffler).
But that ACE bike and this engine would make a nice ilegal 100cc 10HP "BMW like" **** of a bicycle!

 

[hot70cc]

I agree, be sure to post pics of you burn marks on your leg in the summer time while riding with shorts on lol. I'm sure you will figure a way to avoid being burned, but it only takes a grazzze of the leg and your scarred. Not the setup for me thats for sure.

 

[KeepOnKeepnOn]

You can also use silicone sheet as insulation on the pipe too, or fiberglass header tape, to protect your leg. They make oven dishes and mittens out of the stuff. Nice mod, surprised I haven't seen more bikes with a real expansion pipe on them, it makes a huge difference. I'd like to see it go under the bike though.

 

[kevbo]

McMaster-Carr (see catalog page 230) sells silicone heater hose in a number of sizes (1/4" to 6" diameter)) by the foot. I've also purchased this (up to 2" ID) at Westfleet, which is sort of an auto parts store for big trucks and commercial vehicles.