Backfiring

bang · Post by **bang** » Fri Jan 05, 2007 6:35 am

I have read the posts that discuss the isolated odd backfire that can blow off the throttle body but I think this is a different problem. My 2000 1100R consistantly backfires and it is driving me nuts. It has a Staintune/no cat/ baffle is installed. Seems to run fine in every other respect. Lately though, in addition to a series of small pops, it has taken to making an occasional LOUD single bang when throtle comes to near closed position. Have recently adjusted valves to spec. Other than reinstalling the stock pipes (which I am warming up to), does anybody have any ideas? Thanks much!

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Kazushi · Post by **Kazushi** » Fri Jan 05, 2007 8:53 am

If I'm not mistaken there's an O ring between the muffler and the pipes, when that goes bad air gets into the exhaust and pops...

bang · Post by **bang** » Fri Jan 05, 2007 9:36 am

Thanks. I will check the gasket ring.

paithorn · Post by **paithorn** » Fri Jan 05, 2007 10:05 am

Hey, same problem here!

I am using Staintume exhaust/no cat.... alway have some pops in near close throttle position espcially at low gears ( 1 or 2)

Also at low gears, the bike is a little jerky... I know someone here mentioned to remove the O2 sensor...

Any expert views/advice for the pops besides putting back the original exhaust?

Post by **challey** » Fri Jan 05, 2007 11:30 am

I have the same problem, though I'm using the stock can with a Sebring Y-pipe. The frequency varies quite a bit, but the timining is consisten: It happens only when the throttle is shut abruptly. Seems to happen more frequently after a Sea Foam treatment and my riding buddies tell me that there is visible carbon blown out with the exhaust.
It's been suggested the major contributor is air getting in at the Y-pipe/muffler joint but I'm pretty sure I have nice tight fit there. No rideablity issues though.

johno · Post by **johno** » Fri Jan 05, 2007 4:12 pm

I have a full Remus system, and very few, and only small pops every now and then.
You must seal the whole system with good high temp sealer, or you will get the popping.
Also, I think the original cat soaks up a lot of those noises as well, so we dont hear them anyway.
I have removed the O2 sensor, and have a chip-no surging issues.
Throttle body syn may help as well.
Otherwise, use better ear plugs.

bang · Post by **bang** » Fri Jan 05, 2007 7:03 pm

Today I pulled off the the entire exhaust system and carefully checked and cleaned the header connection to the cylinders. No problems, but still some backfireing at certain throtle positions (near closed). If I were very clever and skilled I could ride and avoid that particular throtle point. Also, someone recently suggested that the backfiring is occurring in the Staintune empty can where the catalytic converter used to be. The backfireing being the result of accumulated fuel rich vapors there. A possible solution might be to eliminate the can with a custom straight thru pipe. Another interesting note is that the backfireing does not happen with a cold engine.

johno · Post by **johno** » Fri Jan 05, 2007 8:23 pm

I noticed on some of the Cat replacements that they use a can type of system, not just the straight pipes.
Maybe it has a welding dag. or something inside the collector that is creating a hot spot when engine is warmed up, which maybe the cause.
My Remus is a straight pipe system, no collector.

paithorn · Post by **paithorn** » Wed Jan 17, 2007 8:41 am

I went for a ride recently with a big group of BMWs(almost 20 of various models) Apparently the backfiring is a common thing. It will be more frequent with after market exhaust.

bang · Post by **bang** » Wed Jan 17, 2007 9:35 am

No more backfiring for me. No, I didn't replace the stock exhaust, I installed a Techlusion FI-1031 TFI injection box. Best $215. I ever spent on the bike. With the settings at the suggested starting points for after market exhaust and the oxygen sensor unpluged as they suggest, the problem is gone.

In addition, I have much more control over fuel delivery at all rpm's. Also cures surging I hear, though I wasn't suffering from that. Great product - period.

paithorn · Post by **paithorn** » Thu Jan 18, 2007 7:38 am

Did you order that online? Self install? Mind passing me the website to get one too? Thanks a million!

Post by **challey** » Thu Jan 18, 2007 12:02 pm

I'd love to eliminate the backfiring but since it really hasn't affected rideablity, plan to try some simple fixes first like removing the CCP or O2 sensor. I ran across this site offering the Techlusion FI-1031 TFI for $189 though:http://www.customdynamics.com/motorcycl ... module.htm

bang · Post by **bang** » Fri Jan 19, 2007 10:27 pm

I ordered it online directly from the manufacturer (http://www.techlusion.com/). I think its worh a few more bucks to have the tech support and warranty if needed. Before I ordered it I spoke to their tech guy who confirmed that the particular product would be the solution to my problems and told me he would take it back if it didn't work, and or help me with the install or settings. It was easy and straightforward and I never needed to get back to him.

I installed it myself - very simple plug-in with no wire splicing required. I hate to sound like I'm selling this thing, but in addition to curing the backfiring it has reduced the jerkiness of the on-off throttle positions.

BTW, unpluging the O2 sensor alone will not, in my experience have any noticable effect.