HOW TO: Remove baffles from stock pipes, pics and vids!!!

[MIKE93SVT]

so i couldn't find any info on how to do this, so i tackled it myself. i'm very pleased with the results, even though i didn't remove as much as i originally intended. the bike sounds great, nice deep throaty sound and still has good bottom end. this is only one way to do it, so keep an open mind and improve where you see fit. i haven't taken it for a real ride yet, so there may be some carb tweaks to compensate for less back pressure, however, most of the baffles are still gonna be there, just the end cap was removed.........

(all pics and videos were with my iphone, sorry for the sound quality)



so my bike is a 78 xs650. here's a pic to show what the pipes are that came on mine.

and here's what my tips looked like

you can cut out the back in two different methods:

use a 3 1/4 inch hole saw which is really close and leaves less to grind away

or you can use a drill and make a hole. then use a jig saw or a dremel tool and cut around the outside of the cap

next you need to grind the outlet of the original port. there is a seam there that joins the pipe to the cap, grind enough away until you can knock out the big part of the cap

next take your dremel and cut off as much as the original inner pipe to help hide it from the rear

then using a grinder attachment on your dremel or drill, start smoothing out the leftover metal to the outer pipe to make a smooth appearance

remarkably, rustoleum high temp bbq paint looks just like carbon build up. so after you smooth out all your cuts and it is nice, spray a little in there to hide the bare metal

and here's your final product

here's a video of the stock pipes, no mods at all

and here it is with the end caps removed, but the inner baffles still in place

add any info you may have to improve the mod

 

[heckienawjoe]

awesome! i've always wondered how to do this. i was considering just hacking off the muffler at the rear pegs, but this looks much cleaner.

i wish you had more high quality videos so i could get a better idea of the sound, but great pics. thanks!

 

[MIKE93SVT]

yeah. I don't like the popping sound of the short ass pipes. I can charge my camera and get a better video

 

[PhatTony]

Great write up! This needs to be in the Tech Section!

 

[Travis]

^ it was added yesterday.

 

[Captmilk]

Will they inspect it that way

 

[angus67]

i would definately do that to pipes that still looked that good. if they were rusty, ide hack em at the pegs. does sound deeper. good job.
funny the bbq black. I did the same on my 2003 suzuki marauder 4 years ago when I debaffled it. baffel-ectomy

 

[gaps]

Mike, thanks for this, I plan to give it a go this weekend. Did you need to re-jet the carbs? My 1980 special runs lean already, figure I'll need to do something to compensate. I intend to run the airbox for now, any jetting recipe suggestions?

 

[thedanned]

Sorry to bring back an old thread but I have two questions.

1. I just did this to my 79 and jeebus is it loud. Would the washer trick quiet it down some? I know, I know, I was asking for loud but not this loud!

2. OP: I cant seem to get my dremel into the pipe all the way to cut as far back as you did in the pics. Did you use some kind of extended mandrel for the cutoff wheel?


Thanks

 

[Dyer]

I did this today and the bike sounds sooooo much better!

 

[SeattleUnderliner]

So. dumb question.

does opening the pipes make your bike run richer or leaner in general? Which way should i turn my idle mixture screw to compensate? or, is that not enough, will i need to rejet?

 

[JR Hammer]

I cut my stock mufflers off altogether. It is bloody loud now and I like it-- but the small diameter of the pipes gives the engine a snappety sound when it revs. I think it could be improved a lot with larger diameter pipes and shorty glass packs... and still be plenty loud.

and YES to answer your question. Anytime you drastically change the airflow into or out of the engine, the mixture will also need to be changed to compensate.

opening up the pipes and removing the stock airbox or installing uni-pods will cause the engine to run more lean. when there's more airflow you need to richen the mix so there will be more fuel for the extra air.

if you dont enrich the mixture your bike will run lean and backfire almost constantly. With the mix set properly, the backfire problem vanishes. happy bike = happy biker

 

[Joshuammorris]

I cut my stock mufflers off altogether. It is bloody loud now and I like it-- but the small diameter of the pipes gives the engine a snappety sound when it revs. I think it could be improved a lot with larger diameter pipes and shorty glass packs... and still be plenty loud.

I was thinking about chopping my stock pipes too, does it cause any problems in how the bike runs/idles? I know I'll have to rejet it,but other than that is just cutting my pipes going to be ok?

Also, would I have to go up or down in the jetting?

 

[Travis]

You'll probably have to go up, but not always by as much as you'd think. Modify your exhaust, then reset your mixture screws and go from there with the jetting. Some people to tend to over jet then end up coming back down closer to stock. They may have been better to start with stock, but then I guess you risk running lean.

Be sure you read these guides if you haven't already: http://www.xs650.com/forum/showthread.php?t=43

 

[BruceDeuce]

For those who attempt this. Ive spent $40.00 in cutting disc's. I should have just bought slip ons and cut the exhausts off.

 

[nj1639]

On the stock Special exhaust...I took a four foot length of 5/8ths ground rod and probed the opening in the rear of the exhaust. About a foot and a half to two foot in there's a stop. I then drove the rod through the stop on both mufflers. A bit more free flow and a bit more tone.

 

[pahako]

The metal plate on the back of the muffler is soft enough that you can take a flat screw driver and a hammer, and just go around it like a chisel and punch right through the plate. You will also need to go around the pipe too. When you get the plate off, if you have one of the newer nonslip cutting discs from Dremel, to cut the pipe shorter, you can do the whole job in a few minutes and only use one or two discs. I have done this on a couple of xs's. It will give you a much better sounding bike for zero dollars.

 

[jonasblack]

Im definitely doing this on Sunday, did anyone have any complications after drilling out your pipes? I understand about fuel mixture and such. My dad said he once ran short pipes with no baffles and it ended up burning holes in his valves.

the pipes id be modding are the stock ones, as long as I adjust the mixture I should be okay, correct?

 

[pahako]

Wouldn't hurt to go up one size on your main jet if your running stock air boxes. If you have pod filters, you might want to go up 2 sizes on your mains and 1 up on your pilot jet.

 

[crescendo]

I must admire your post. Your work is really appreciable. It helps many of us. Pictures were needed to understand the method properly. So thanks for helping us with such useful post.