DR650SE muffler options

[NordieBoy]

Had a nice light stainless muffler made up by GPCustom (he of bash plate fame) Problem now is HORRENDUS backfiring on over -run and FLAME being expelled after shut down. Would not have thought it would be that lean. Will have to modify the jets as above but don't want to sacrifice too much fuel economy. (would probably be a 170 main) I will probably get the diameter of the can reduced first. Any thoughts gentlemen?

What's your current jetting?

[cold comfort]

Standard (140 i believe) haven't got around to changing anything there, including air box. I know its prob a case of trial and error but what is your best guess on size considering the magnitude of the problem?

[gpcustom]

dont worry i willl sort the problem. I dont know why this has happened. The only thing that ive done diffrent on your pipe was adding the chamber to the front of the muffler maybe this is causeing the problem. Im going to cut muffler open and reduce the inner perf pipe and get rid of the chamber then fit back on and see what happens

Im verry dissapionted with myself have never had this happen befor

[NordieBoy]

If you've kept the airbox stock then the jetting shouldn't need to change.

[NordieBoy]

dont worry i willl sort the problem. I dont know why this has happened. The only thing that ive done diffrent on your pipe was adding the chamber to the front of the muffler maybe this is causeing the problem. Im going to cut muffler open and reduce the inner perf pipe and get rid of the chamber then fit back on and see what happens

Im verry dissapionted with myself have never had this happen befor

You don't want to shift to Nelson do you?

I need a custom pipe on this baby...


And some welding to be done...
And a bash plate...

[gpcustom]

lol thats cool is that a 4cly i see in there??

not keen to look at doing any mufflers im im um whats the word

I wiil sort cold comforts muffler i made a pipe not to long a go for a xr 600 and i didnt have this problem i dont understand whats gone so wrong ??

[cold comfort]

Hey dude- no reflection on your excellent fabrication skills. Don't take my post personally. Could just be my dodgy DR. It looks like, as you say, by reducing the inner diameter it may well sort the issue. As Fran says there is no point jumping into carb mods until that's eliminated.

[NordieBoy]

lol thats cool is that a 4cly i see in there??

not keen to look at doing any mufflers im im um whats the word

I wiil sort cold comforts muffler i made a pipe not to long a go for a xr 600 and i didnt have this problem i dont understand whats gone so wrong ??

1981 GSX400ADV or DR400F.

With an open pipe a stock jetted DR will make a racket on the over-run.

Hell, even a nicely dynojetted DR will backfire a lot. The pipe just dictates how loud.

[DR650gary]

The pipe just dictates how loud.

Loud...Like it lots.

Hey, what's with all the deaths on the road in your area? Your local commander blames old farts like me. Seems like you are going to get stopped for no reason, just a chat. Pity they don't do that for all the dickheads in cars, changing lanes without indicating, drinking coffee..texting...calling...changing stations while driving. Just came back from Auckland, by car unfortunately, and I am amazed by the poor and inattentive driving on the road. Also surprised by the lack of bikes on the roads in Auckland. Seems the white shoe brigade would rather listen to the radio on their homeward commute for an hour or so than flick through the traffic.

[gpcustom]

Hey dude- no reflection on your excellent fabrication skills. Don't take my post personally. Could just be my dodgy DR. It looks like, as you say, by reducing the inner diameter it may well sort the issue. As Fran says there is no point jumping into carb mods until that's eliminated.

sorry didnt mean for it to sound like that im not taken it personall at all. I just havnt had that happen befor and its got me stumped . Ive been awake since 5am thinking about it ive decided to scrap that muffler and start again ive had a better idea

[dino3310]

Loud...Like it lots.

Hey, what's with all the deaths on the road in your area? Your local commander blames old farts like me. Seems like you are going to get stopped for no reason, just a chat. Pity they don't do that for all the dickheads in cars, changing lanes without indicating, drinking coffee..texting...calling...changing stations while driving. Just came back from Auckland, by car unfortunately, and I am amazed by the poor and inattentive driving on the road. Also surprised by the lack of bikes on the roads in Auckland. Seems the white shoe brigade would rather listen to the radio on their homeward commute for an hour or so than flick through the traffic.

thats why we call them and only them Jafa's

[DR650gary]

thats why we call them and only them Jafa's

Found the driving around Te Rapa interesting at best

Mind you, just north of where I live is Levin and I think you have to tick "Idiot Driver" on your CV before you are allowed to move in. I think riding a bike makes you more aware but I do feel there has been a definite drop in standards on the road in recent years.

I guess as long as we all ride with more awareness we will survive and probably reduce those pointless deaths that Tasman has experienced over the last 9 months.

[cold comfort]

Could we keep this thread to the topic please "DR650SE MUFFLER OPTIONS"

[gpcustom]

well we are about to try out muffler #2 hopefully ive got rid of the flame problem alltho it would have looked cool at night time

I will be fitting the new muffler tomorow so fingers crossed and will post some pics

[DR650gary]

Ordered jet kits for DR650 and DR200 to go with the Pro Circuit and Big Dog exhausts and also grabbed one for the ZRX as I have an aftermarket system on that as well. $279 landed in NZ for all so pleased with that.

Cheers