Announcement

Collapse
No announcement yet.

Rejetting for straight pipes?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    #16
    Originally posted by bohisboh View Post
    You're saying going back to stock pipes would be best?
    I wouldn't say best, but almost certainly they would be better than untuned straight pipes. Defining what you mean by 'best' would help some. If you want smooth running with minimal noise and moderate power then stock is likely best. If you want more power and want or don't mind a louder exhaust then an aftermarket pipe will be best.


    Originally posted by Big T View Post
    Definitely
    Originally posted by Runeight View Post
    Stock is always best.
    Nonsense. Aftermarket pipes are just fine and will work just as well as stock if done properly.


    Originally posted by bohisboh View Post
    Makes perfect sense to me. Is there any black exhaust systems you would recommend that would fit this make/model whilst still achieving a throaty sound? I've been attempting to dig but don't know the first thing.
    As noted, take off H-D mufflers are all over the place for cheap and would be a good first try. If you don't like the chrome some sandpaper and header paint can make them black in an afternoon. I doubt you are going to get anything that sounds throaty, the engine is small at 650cc and just doesn't have the displacement to sound very big and deep.


    Mark
    1982 GS1100E
    1998 ZX-6R
    2005 KTM 450EXC

    Comment


      #17
      "Throaty" is different on a smaller cc bike. I would describe my exhaust as such at lower rpm. To get to that sound, you are going to let a lot of noise out on hard acceleration. I'm using a 4-1 with megaphone muffler. I had mine powdercoated (ceramic) instead of painted. Header wrap helped accent the rumble and tame a bit of the sound volume.

      Comment


        #18
        Originally posted by mmattockx View Post


        I doubt you are going to get anything that sounds throaty, the engine is small at 650cc and just doesn't have the displacement to sound very big and deep.


        Mark
        You should hear my 550/675. Throaty it has, at least when it isn't at 10,000 RPM.
        http://img.photobucket.com/albums/v5...tatesMap-1.jpg

        Life is too short to ride an L.

        Comment


          #19
          Originally posted by GSCafe View Post
          "Throaty" is different on a smaller cc bike. I would describe my exhaust as such at lower rpm. To get to that sound, you are going to let a lot of noise out on hard acceleration. I'm using a 4-1 with megaphone muffler. I had mine powdercoated (ceramic) instead of painted. Header wrap helped accent the rumble and tame a bit of the sound volume.
          What specific system did you get, if you don't mind me asking?

          Comment


            #20
            Originally posted by mmattockx View Post
            I wouldn't say best, but almost certainly they would be better than untuned straight pipes. Defining what you mean by 'best' would help some.
            By best I mean optimally rideable including freeway speeds. And I wouldn't mind a little more 'oomph' and some noise, while not being obnoxious.

            Comment


              #21
              Originally posted by bohisboh View Post
              By best I mean optimally rideable including freeway speeds. And I wouldn't mind a little more 'oomph' and some noise, while not being obnoxious.
              Optimally rideable really is a jetting issue more than the pipe, but some pipes can be extremely hard to tune for. It sounds like you want an aftermarket exhaust system in that case. It will still require rejetting, but shouldn't be goofy like your straight pipes likely are. Do you have some pics of the bike showing the exhaust system so we can maybe see what we are dealing with?


              Mark
              1982 GS1100E
              1998 ZX-6R
              2005 KTM 450EXC

              Comment


                #22
                Yes I found an older one. Apparently I can only have one file per post? No idea I'm on my phone.
                20160518_145824.jpg

                Comment


                  #23
                  Originally posted by mmattockx View Post
                  ...the engine is small at 650cc and just doesn't have the displacement to sound very big and deep.
                  Mark
                  An old Brit 650 twin with open pipes sounds pretty mean. Although the one I'm recalling may have been modified, at first I thought it was a Harley.
                  1982 GS1100E V&H "SS" exhaust, APE pods, 1150 oil cooler, 140 speedo, 99.3 rear wheel HP, black engine, '83 red

                  2016 XL883L sigpic Two-tone blue and white. Almost 42 hp! Status: destroyed, now owned by the insurance company. The hole in my memory starts an hour before the accident and ends 24 hours after.

                  Comment


                    #24
                    Originally posted by bohisboh View Post
                    What specific system did you get, if you don't mind me asking?

                    Kerker full 4-1 header with megaphone muffler was on the bike when I bought it. The original exhaust is rusted out. I've really come to appreciate the sound of the Kerker. I don't think it is sold anymore. (for '79 GS550)

                    Comment


                      #25
                      Originally posted by bohisboh View Post
                      Yes I found an older one. Apparently I can only have one file per post? No idea I'm on my phone.
                      [ATTACH=CONFIG]45653[/ATTACH]
                      Ouch. That looks like someone cut the stock pipes and then just tack welded on the extra pipe. In that case your easiest first try may be the Harley take off mufflers if they fit the head pipes where they were cut. That would get you closer to being right with the stock jetting. No matter what you do you are going to have to open the carbs up and see what you have and adjust to suit the exhaust you end up with.


                      Originally posted by Rob S. View Post
                      An old Brit 650 twin with open pipes sounds pretty mean. Although the one I'm recalling may have been modified, at first I thought it was a Harley.
                      Yeah, but that has 325cc cylinders whereas OP's 650 has 162.5cc cylinders. Not nearly as much oomph from the smaller cylinders.


                      Mark
                      1982 GS1100E
                      1998 ZX-6R
                      2005 KTM 450EXC

                      Comment


                        #26
                        Originally posted by mmattockx View Post
                        Yeah, but that has 325cc cylinders whereas OP's 650 has 162.5cc cylinders. Not nearly as much oomph from the smaller cylinders.
                        Actually, they are 168.25cc, but who's counting?

                        AND, ... since two of them come together, they are pushing 336.5cc through each of the mufflers, which is pretty darn close to the 325cc that you quoted.

                        .
                        sigpic
                        mine: 2000 Honda GoldWing GL1500SE and 1980 GS850G'K' "Junior"
                        hers: 1982 GS850GL - "Angel" and 1969 Suzuki T250 Scrambler
                        #1 son: 1986 Yamaha Venture Royale 1300 and 1982 GS650GL "Rat Bagger"
                        #2 son: 1980 GS1000G
                        Family Portrait
                        Siblings and Spouses
                        Mom's first ride
                        Want a copy of my valve adjust spreadsheet for your 2-valve per cylinder engine? Send me an e-mail request (not a PM)
                        (Click on my username in the upper-left corner for e-mail info.)

                        Comment

                        Working...
                        X