I was concerned that I was running too hot or something until my buddys did the same thing. It did look kinda wimpy but it lasted for a few rides. We ride hard but I was wondering if anyone else had this problem before I contact Big Gun. Thanks.

 

Are you guys running too lean? The exhaust has to be really hot to melt the screen. Have you read the spark plugs? What are they telling you? I assume if he's your buddy you kinda set the machines up the same, that's why you both melted the screens. Nevermind the screens fix the problem before you burn up a piston!!![img]i/expressions/face-icon-small-smile.gif[/img]

 

i blow mine out after about a week. sent them the remains of the screen and they sent me a new one and some decals to go with it.

 

Yep,... mine blew away too! I called Big Gun and they sent me a new one, and suggested that I install it in the reverse direction as the original one. It now sticks out farther to the end of the pipe. It has lasted for several rides. I recently had my bike run on a dyno (mobiledyno.com) and compared my BG to an HMF pipe. The HMF with the stock head pipe had basically the same max HP of 41.5 as my full BG set up, but it had a 5 hp advantage over the BG from 3000 to 6500 rpm. I noticed the HMF pipe did not have the spark arrestor in it, so we removed my BG screen, and whola... they overlay each other on the graphs. So,.. for the extra 5 hp in the 3-7k rpm range, I now leave it out. I was also concerned that I was running lean, and thus hot, but the dyno showed that I was only a little lean at the top end. I did up my dynojet set up to 148/150's ( from the reccomended 146/148)

 

Thanks for the replies. I failed to mention I did all the checks (plugs,ect.) this thing runs excellent (not my first popcicle stand). Big gun replied and said to send the remains and they would send me a thicker one. They said the Raptor and DS have the same problem. Not a problem really, just glad I caught it before the DNR did. Thanks again.

 

outstanding info wilderp. now which one sounds better? the hmf or the big gun.

 

I blew mine out of my Big Gun it happened about two months ago. I still remember when it happened I blew a 4ft flame out of my pipe and it was running rich. I believe the jets that they require for it are running it to rich and should come down a notch. I just said screw it and took it out running it without that damn screen. Ill get another one when I head to glamis for thanksgiving.

 

otterbob,
Actually I only heard the last run with the screen out of the BG. But since it was in the mobile dyno trailer, with only the back end open, it would have been kinda hard to tell (it's really loud running a bike at 8-9,000 rpm in a three sided trailer) [img]i/expressions/face-icon-small-smile.gif[/img]

 

i blew mine out too, i have a big gun head pipe with a GYTR carbon fiber silencer

 

I ALSO BLEW MINE OUT. I SPOKE WITH PAUL AT BIG GUN AND HE SAID TO SEND IT TO HIM AND HE WOULD SEND ME A NEW ONE TO RUN IN THE OPPOSITE DIRECTION. hE SAID THE DISTIBUTOR (MOTOWORLD PROBALLY INSTALLED IT IN THE WRONG DIRECTION.

HEY SONIC I NOTICED YOU HAD THE QUIET CORE HOW QUIET IS IT? PAUL AT BIG GUN SAID THEY HAVE NOT BEEN ABLE TO MEET THE 94DBL. ON THE RAPTOR YET.