We just started making our own. We found with 1" we lost bottom end power no real gain with RPM's maybe in the long run but we are doing 1/8 mile tests. 3/4" was just about right and a 3/4" to 1" will give you about everything a stock motor will put out till the valves start to make noise. Also all of our pipe are 16" long. 3/4" to 1" was also 16" long with 8"-3/4" and 8"-1" (confusing?)
Also guys it really does help to try and recreate the D shape in the port opening. With the box stock exhaust it was total crap, but with the new ones we do now, we shape the end of the pipe on a HF anvil the little one it has a perfect D shape that is conforms to when beat(messaged) on....
Also I will tell you what this pipe testing didn't help us out at Kings Speed Way last weekend at all....haha My first time racing a bike, mini, anything on 2 wheels in the dirt. And I think I finished 2nd to last it's not like street racing AT ALL. In the dirt coming out of a corner with these mini's spinning the rear tire in clay. Fun as heck though.
Also guys it really does help to try and recreate the D shape in the port opening. With the box stock exhaust it was total crap, but with the new ones we do now, we shape the end of the pipe on a HF anvil the little one it has a perfect D shape that is conforms to when beat(messaged) on....
Also I will tell you what this pipe testing didn't help us out at Kings Speed Way last weekend at all....haha My first time racing a bike, mini, anything on 2 wheels in the dirt. And I think I finished 2nd to last it's not like street racing AT ALL. In the dirt coming out of a corner with these mini's spinning the rear tire in clay. Fun as heck though.
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I have Chris sending me a custom exhaust.
As for the short one on the bike now: The short header and thread on muffler worked good. Just too loud for my neighborhood. I had my neighbor come over and asked me if I took the muffler off because it was loud. The factory exhaust sucks for me only because it does not exit out the back of the bike and it has burnt a couple people. I need something that sounds as quiet as the factory because of my situation. I know it may hinder performance a little, but... Let me know if you have any ideas. And I am going to sell the two small headers with mufflers for $15 each.
As for the short one on the bike now: The short header and thread on muffler worked good. Just too loud for my neighborhood. I had my neighbor come over and asked me if I took the muffler off because it was loud. The factory exhaust sucks for me only because it does not exit out the back of the bike and it has burnt a couple people. I need something that sounds as quiet as the factory because of my situation. I know it may hinder performance a little, but... Let me know if you have any ideas. And I am going to sell the two small headers with mufflers for $15 each.
those sausage style mufflers are about as quiet as you're going to get unless you keep it stock.
your neighbor sounds like an asshole if he's bitching about that being too loud. none of mine have said anything about me ripping around the neighborhood with an open header. the guy across the street did get mad when we were testing out some modded 5hp Briggs motors on methanol. they were hahahahaing loud and it was sort of late (8:30pm).
your neighbor sounds like an asshole if he's bitching about that being too loud. none of mine have said anything about me ripping around the neighborhood with an open header. the guy across the street did get mad when we were testing out some modded 5hp Briggs motors on methanol. they were hahahahaing loud and it was sort of late (8:30pm).
You could always use the manifold and pipe from the custom assembly and weld the stock muffler to it all.
stock muffler
stock manifold
custom set-up
notice this is still essentially a DB, but it has been stretched and converted to a trike. The clone is still in stock location, and rear grab bar and fender mount are still at stock height and position, only farther back.
this one we removed the stock mounting bracket and repositioned it to the new set-up. worked quite well.
stock muffler
stock manifold
custom set-up
notice this is still essentially a DB, but it has been stretched and converted to a trike. The clone is still in stock location, and rear grab bar and fender mount are still at stock height and position, only farther back.
this one we removed the stock mounting bracket and repositioned it to the new set-up. worked quite well.
I like it! This might work for me. My buddy is going to try a couple tricks for me this weekend.:weld: One is two B&S mufflers in a row and the other is extending the stock muffler to exit out the back. Should I get two of the bigger B&S mufflers (3/4)? or two of the smaller (1/2) and try? I don't need anymore top end. The bikes go 35mph now and am happy with the speed.
