just a note with my quad it has way more wheelie power with stock exhaust than with the d.g.! top end suffered noticeably but i mostly ride at nite and want quiet! I.M.O. dont buy the d.g rcm

 

Your stock exaust must be blown out. I noticed a HUGE increse in power with the DG over stock.

 

You guys JUST changing the exhaust???? Or are you changing other things too at the same time as the exhaust? According to the sim, power should go up across the board with less backpressure. Running an open pipe with no baffles actually increases backpressure at low rpms. It must,,, or else it would run better.

I went for a ride today even though it was wet. I didn't have any problems with wheelies and I "think" I notice more power. Won't be sure till I ride for a while and get out of the mud.

My shop vac has the leaf blower attachment and I hooked it up to the exhaust before and after I took the baffles out. There actually wasn't that much of a flow difference. The spark arrestor gets in the way too much. There was an increase though, proven by the spark plug and the increase in sound. I need to find/make a bigger spark arrestor. Maybe that's my next project.

 

<div class="FTQUOTE"><begin quote>Originally posted by: JustRandy

You guys JUST changing the exhaust???? Or are you changing other things too at the same time as the exhaust? According to the sim, power should go up across the board with less backpressure. Running an open pipe with no baffles actually increases backpressure at low rpms. It must,,, or else it would run better.



I went for a ride today even though it was wet. I didn't have any problems with wheelies and I "think" I notice more power. Won't be sure till I ride for a while and get out of the mud.



My shop vac has the leaf blower attachment and I hooked it up to the exhaust before and after I took the baffles out. There actually wasn't that much of a flow difference. The spark arrestor gets in the way too much. There was an increase though, proven by the spark plug and the increase in sound. I need to find/make a bigger spark arrestor. Maybe that's my next project.</end quote></div>


Also ran without the airbox lid and UNI filter..
Never got a lunch today, oddly busy at work, will get yer clutch gear count in a few minutes.

About the exhaust again, last year me and some buddies were on a LONG ride, bout halfway thru I noticed a lil "extra" power thought cool, got the dial a jet dialed finally!! At a beer break, my friends pointed out that my bike was pretty loud, I didn't notice cause o the helmet i guess?? We fired it up and started lookin around. The "gasket" for lack of a better word between the header and the muffler had blown out, on stock unit! After that was when I bought the DG and had same results....

Before DG, ran around a lil with just header[img]i/expressions/face-icon-small-happy.gif[/img] Kinda bogged down till you got movin, but hauled azz after about 10mph!! Sounded like a Harley too![img]i/expressions/devil.gif[/img]

66 and 14 is your clutch basket count by the way.. Counted twice, probably right.[img]i/expressions/face-icon-small-blush.gif[/img]

 

66 is less than I thought.... I was thinking 70 or so like the 230e.

My gasket or whatever between the primary pipe and muffler has been blown since I've had the quad. Also, the oil drain bolts on the underside of the muffle are out in mine. The bolt closest to the engine makes a sh!tload less backpressure. I used the hole to gauge how much flow the rest of the exhaust had. Hook it up to the leaf blower and hold my finger on the hole and the blower slows down a lot! Take my finger off and a big blast of air comes out of that tiny hole. So, take the bolt out on stock mufflers.

If you ran without the airbox lid and a UNI filter you probably got some boost from those and it was compounded by the high flow exhaust. The exhaust richened the mixture and the airbox lid and UNI leaned the mixture. Together, it worked out.

I have the KN and the bigger carb (of course no air lid, lol).... Now I need to get the exhaust to be as good as the intake.

 

mine is stuck? exhaust thingy between muffler and pipe , exhaust that i have never had internals removed. Poolgod u had a different exhaust than i have,mine is just a big hole and some packing. I am looking into getting the exelerator exhaust cause u can tune by disks by the looks of it

 

<div class="FTQUOTE"><begin quote>Originally posted by: 270quadsportguy

mine is stuck? exhaust thingy between muffler and pipe , exhaust that i have never had internals removed. Poolgod u had a different exhaust than i have,mine is just a big hole and some packing. I am looking into getting the exelerator exhaust cause u can tune by disks by the looks of it</end quote></div>

You can tune it, how does that work by the way? I understand more discs = less back pressure, less discs = more backpressure. Got a way to put it so someone as dumb as myself can understand the benefits either way?

 

Supertrapp FAQ might help u understand the discs thing. http://www.supertrapp.com/resource/faqs.asp


I had a thought last night about why we lose power at low rpms when running an open pipe. Maybe its the lack of backpressure that lets the combustion gases escape out the exhaust more instead of pushing the piston down because the exhaust valve opens before the piston gets to the bottom. Once the exhaust valve opens, the muffler and the piston are linked by a spring made of air. This makes more sense than thinking the backpressure goes up because of an open pipe.

I kinda like the tunability of the discs. One thing I noticed while playing with the leaf blower, I could put my hand over the tail pipe and make it a lot quieter but not reduce flow. I might play around with a saucer-shaped piece of metal covering the tail pipe and leaving only a small gap.

 

Excellent! Thank you!

 

I just got my 13 tooth front today (39 rear). Put it on n went for a ride. Revved it up in 1st, sat on gas tank and dumped the clutch n nearly fell on my azz! I tried it again while standing and leaning over the handlebars and it STILL brought up the front. It wouldn't do any of that with the 12. In 2nd, it will start spinning the tires, but quickly bog down and just start accelerating. It would do that with the 12 too. My friend's 250 with the smaller back tires and 11/39 will start in 3rd pretty good and 4th about like mine does in 2nd now.

I think the 12/39 accelerates faster because I can keep the revs in the powerband more. But the 13/39 starts off quicker and by 4th gear I can really feel it pulling. I think in a race the 12 would be in front and eventually would be passed by the 13. So, now the goal is to get enough power out of it to be able to do 2nd like it does 1st now. [img]i/expressions/face-icon-small-smile.gif[/img]

I might try the 13/41 combo just to see.... That should be in the middle of 12/39 and 13/39.