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  • Carburetor rebuild

    I just got a Hawk from my uncle that I have been lusting over for years. It has been in storage for a few years and is gonna need to have the carbs rebuilt. Should I just get a gasket kit from Honda or splurge for a dynojet? The bike has no mods as of now.

  • #2
    Most people here use Factory Pro and not Dynojet.
    Brian - Richland, WA
    1991 Hawk GT

    Comment


    • #3
      just follow the steps illustrated in the service manual for a simple cleaning, paying attention to idle jets. usually, most "carb kits" aren't needed, just clean things up and reuse parts.

      post-3647-0-85981000-1347898810.jpg

      new float bowl gaskets can be made from standard industrial O-rings. -.041.
      Last edited by squirrelman; 06-30-2022, 04:26 PM.
      "It's only getting worse."


      MY rides: '97 VFR750, '90 Red Hawk, '88 Blue/Black Hawk, '86 RWB VFR700 (3), '86 Yamaha Radian, '90 VTR250, '89 VTR250 (2), '73 CB125, '66 Yamaha YL-1

      Sold: '86 FJ1200, '92 ZX-7, '90 Radian, '73 CB750, '89 all-white Hawk, '88 blue Hawk, '86 FZ600, '86 Yam Fazer 700 , '89 VTR250, '87 VFR700F2, '86 VFR700F.

      Comment


      • #4
        Originally Posted by squirrelman
        just follow the steps illustrated in the service manual for a simple cleaning, paying attention to idle jets. usually, most "carb kits" aren't needed, just clean things up and reuse parts.

        post-3647-0-85981000-1347898810.jpg
        This. If its stock you shouldn't need anything. just a couple screwdrivers, some stranded wire and get at er
        Don't spend money and buy, spend time and learn.

        Comment


        • #5
          Some people just keep it stock.
          Gino
          Chain Roller

          NEVER UNDERESTIMATE THE PREDICTABILITY OF STUPIDITY

          2012 CCS LRRS ULSB Champion
          2012 CCS LRRS P89 Champion
          2008 CCS ULSB National Champion
          LRRS HAWK GT Racer CCS Expert #929
          ECK RACING

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          • #6
            Thanks for the info guys. It's leaking from the left drain screw. I removed it, cleaned it, and it's still leaking plus it's only hitting on one cylinder so I suspect some nasty stuff in the carbs. Gonna go ahead and change the plugs while I'm this far in. Also, any recommendations on air filters? K&N doesn't make one anymore. All I'm finding is Hi-flow brand. I'd like to get one that is cleanable.
            Last edited by CMilam; 06-30-2022, 04:11 PM.

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            • #7
              in addition to the fsm, there is an excellent tutorial on cleaning hawk carbs on this site.

              leaking from drain screws is very, very rare, so suspect damaged parts.

              "It's only getting worse."


              MY rides: '97 VFR750, '90 Red Hawk, '88 Blue/Black Hawk, '86 RWB VFR700 (3), '86 Yamaha Radian, '90 VTR250, '89 VTR250 (2), '73 CB125, '66 Yamaha YL-1

              Sold: '86 FJ1200, '92 ZX-7, '90 Radian, '73 CB750, '89 all-white Hawk, '88 blue Hawk, '86 FZ600, '86 Yam Fazer 700 , '89 VTR250, '87 VFR700F2, '86 VFR700F.

              Comment


              • #8
                Originally Posted by squirrelman
                in addition to the fsm, there is an excellent tutorial on cleaning hawk carbs on this site.

                leaking from drain screws is very, very rare, so suspect damaged parts.
                Where can I find tutorial? I'm not a novice at this but any tips and heads-up are welcome.

                Comment


                • #9
                  Originally Posted by CMilam
                  Thanks for the info guys. It's leaking from the left drain screw. I removed it, cleaned it, and it's still leaking plus it's only hitting on one cylinder so I suspect some nasty stuff in the carbs. Gonna go ahead and change the plugs while I'm this far in. Also, any recommendations on air filters? K&N doesn't make one anymore. All I'm finding is Hi-flow brand. I'd like to get one that is cleanable.
                  If it is leaking from the drain screw then it is an issue with the O-ring. Not a really strange part to find but probably a little hard to figure out the size but a cheap and effective method for getting the right one would be to go to Harbor Freight (if you are in the continental US) and purchase their metric o-ring kit. Chances are high it will be in there and you won't spend a lot of money on it, plus have some spares to boot. 9 bucks well spent -


                  Amazing deals on this 397 Piece Nitrile Metric O-Ring Assortment at Harbor Freight. Quality tools & low prices.

                  88 Blue Hawk GT - Under construction but rideable (guest approved)
                  89 BlackHawk 2.0 - On the lift and being assembled
                  90 Hawk GT (color as to yet be determined) - Still on the shelf in crates

                  Comment


                  • #10
                    ^^ you might be correct but i believe drain screws on hawks should seal fine without O-rings just by the interlocking of the threads.
                    Last edited by squirrelman; 07-01-2022, 01:20 AM.
                    "It's only getting worse."


                    MY rides: '97 VFR750, '90 Red Hawk, '88 Blue/Black Hawk, '86 RWB VFR700 (3), '86 Yamaha Radian, '90 VTR250, '89 VTR250 (2), '73 CB125, '66 Yamaha YL-1

                    Sold: '86 FJ1200, '92 ZX-7, '90 Radian, '73 CB750, '89 all-white Hawk, '88 blue Hawk, '86 FZ600, '86 Yam Fazer 700 , '89 VTR250, '87 VFR700F2, '86 VFR700F.

                    Comment


                    • #11
                      Originally Posted by CMilam
                      Also, any recommendations on air filters? K&N doesn't make one anymore. All I'm finding is Hi-flow brand. I'd like to get one that is cleanable.
                      i suggest you avoid Unifilter as their foam disintegrates into dust after a few years.stock filters are good but kinda pricey.
                      Last edited by squirrelman; 07-01-2022, 01:37 AM.
                      "It's only getting worse."


                      MY rides: '97 VFR750, '90 Red Hawk, '88 Blue/Black Hawk, '86 RWB VFR700 (3), '86 Yamaha Radian, '90 VTR250, '89 VTR250 (2), '73 CB125, '66 Yamaha YL-1

                      Sold: '86 FJ1200, '92 ZX-7, '90 Radian, '73 CB750, '89 all-white Hawk, '88 blue Hawk, '86 FZ600, '86 Yam Fazer 700 , '89 VTR250, '87 VFR700F2, '86 VFR700F.

                      Comment


                      • #12
                        Originally Posted by squirrelman
                        ^^ you might be correct but i believe drain screws on hawks should seal fine without O-rings just by the interlocking of the threads.
                        They may. I personally have never known for sure if there was a compression element to it. I've never seen witness marks on the tip of the screw so I've just assumed the O-ring sealed more than any other compression devices. Usually the kits I buy have them so I replace them anyways and No leaks at this point so either they worked or something else worked, lol.

                        Also Squirrel, I have always been curious what makes that happen to the UNi filters and the best I can figure is maybe someone cleaned them with a solvent or maybe oiled them with the wrong oil (or maybe didn't oil them at all). I figure solvent and long sessions of being dry and hot is bad on the foam, but I have no way to confirm or prove that. I just know I have had them for years and no issues on some of my own bikes so not sure if I have just been lucky or whatever. FWIW all I do for cleaning is warm water and dish soap, then very light oiling with the UNI oil. I've definitely seen some destroyed on some project bikes though, especially ones that have been sitting for a long time so it's always made me question what does that to them.
                        88 Blue Hawk GT - Under construction but rideable (guest approved)
                        89 BlackHawk 2.0 - On the lift and being assembled
                        90 Hawk GT (color as to yet be determined) - Still on the shelf in crates

                        Comment


                        • #13
                          Originally Posted by rpcraft
                          (or maybe didn't oil them at all).
                          I'm guessing this.. but they are cheap. They cost what filling the hawks gas tank once costs.m They are not a part that you need to keep for the rest of your days. Wearables in my world.

                          Don't spend money and buy, spend time and learn.

                          Comment


                          • #14
                            I used to clean my Unis with warm and dish soap and re-oil with filter oil. They lasted maybe 6-7 years before starting to disintegrate. I now do not oil or wash them. I just shake the dirt off once in a while. Looking good so far (maybe 4-5 years now). Those numbers are just guesses off the top of my head. I have records at home but I'm not at home right now.
                            Brian - Richland, WA
                            1991 Hawk GT

                            Comment


                            • #15
                              The tip of the drain screw into the aluminum carb bowl is absolutely what seals it. The o-ring will prevent some very slight weeping that can occur. It's always best to maintain matched sets of drain screws / float bowls. If installing new screws, you should seat and un-seat them a few times so they find their new "home".

                              If you've ever removed the screws from nasty float bowls, there is a definitive line where the conical tip sealed against the float bowl and the very tip looks like the rest of the float bowl.
                              Last edited by Captain 80s; 07-01-2022, 12:38 PM.
                              "I couldn't afford NOT to buy it!"

                              Comment

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