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Not a GS, but got a new bike and have some questions...

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    Not a GS, but got a new bike and have some questions...

    Ok so we got my wife a 1982 honda CM450 and i have some technical stuff to figure out on it and i know people here actually know their ish.
    We knew when we bought the bike that it would need some work and messing around with to get it fully working properly. The more i started to dig at it the more that it became apparent that the PO was a bit of a clown. he seems like a nice guy but doesn't know bikes that well. he was fixing it up for his wife but she didn't like it so he got her a 400 honda with an automatic transmission.
    The only real difficulty that I'm having with the bike now is the flipping carbs. I swear they're off of a bigger bike, but i've looked at a service manual and they look to be what should be on the bike. they're a bugger to get onto the boots coming from the engine because the diameter of the carbs is a little bit larger then the diameter of the boots.
    anyway so when i got the bike, the boots from the airbox to the carbs where cut off at the airbox side so i had to get new ones of those before i could tell what would be going on when i got everything together. before getting the boots on the bike would only rev if it was at full choke and even then it would hesitate before revving up, so it was running ghastly lean right? (i always mix up what signals mean what). I pulled the carbs and cleaned them out, they where pretty clean to begin with, and finally got everything together how it should be on the bike today, but now it idles quite high and when it is revved up it hangs for a bit, which means its running too rich now right?
    I didn't get a chance to take it out for a spin because the garage door is frozen shut still. I'm living in calgary now and this winter has been brutal

    Since the carbs that i have on there are such a pain to get to (have to take off the rear fender to move the airbox back to put the carbs back on. the bike has been chopped and customised a bit) could I put pod filters on it and have it run well? and where would i find a carb kit for a bike like this?
    also i'd want to move down in sizes of the jets if the whole range of the carbs is running rich right?


    on another note, i just used a por 15 tank sealer kit on my 82 GS1100E and whatever connects the float to the fuel gage unit thing has totally gone missing, anybody have any pics of what type of bolt or whatever it is so i can rig something up for that that'll hold the float to the rod that its supposed to be connected to?

    #2
    Wow not even a reply, its a GSR first!
    anybody know of a good honda forum where somebody might know about these bikes?

    Comment


      #3
      Originally posted by Talon View Post
      Ok so we got my wife a 1982 honda CM450 and i have some technical stuff to figure out on it and i know people here actually know their ish.
      We knew when we bought the bike that it would need some work and messing around with to get it fully working properly. The more i started to dig at it the more that it became apparent that the PO was a bit of a clown. he seems like a nice guy but doesn't know bikes that well. he was fixing it up for his wife but she didn't like it so he got her a 400 honda with an automatic transmission.
      The only real difficulty that I'm having with the bike now is the flipping carbs. I swear they're off of a bigger bike, but i've looked at a service manual and they look to be what should be on the bike. they're a bugger to get onto the boots coming from the engine because the diameter of the carbs is a little bit larger then the diameter of the boots.
      anyway so when i got the bike, the boots from the airbox to the carbs where cut off at the airbox side so i had to get new ones of those before i could tell what would be going on when i got everything together. before getting the boots on the bike would only rev if it was at full choke and even then it would hesitate before revving up, so it was running ghastly lean right? (i always mix up what signals mean what). I pulled the carbs and cleaned them out, they where pretty clean to begin with, and finally got everything together how it should be on the bike today, but now it idles quite high and when it is revved up it hangs for a bit, which means its running too rich now right?
      I didn't get a chance to take it out for a spin because the garage door is frozen shut still. I'm living in calgary now and this winter has been brutal

      Since the carbs that i have on there are such a pain to get to (have to take off the rear fender to move the airbox back to put the carbs back on. the bike has been chopped and customised a bit) could I put pod filters on it and have it run well? and where would i find a carb kit for a bike like this?
      also i'd want to move down in sizes of the jets if the whole range of the carbs is running rich right?


      on another note, i just used a por 15 tank sealer kit on my 82 GS1100E and whatever connects the float to the fuel gage unit thing has totally gone missing, anybody have any pics of what type of bolt or whatever it is so i can rig something up for that that'll hold the float to the rod that its supposed to be connected to?

      sounds to me like a bad filter or something if your running to rich then you have to much fuel and not enough air. are you sure the Jets in there are the right sizes right now? if you get pods it makes logical sence that they would fit but if the bike has CV carbs then I would say just stick with the air box. i havnt been able to find a old honda bike web site becasue if my 550F I have been looking for one but not found one.

      Hope I helped
      Jake

      Comment


        #4
        Did you pull the jets out and clean them all? Go through the carb cleaning links on BikeCliff's page.

        I think its still lean but not as bad.
        sigpic Too old, too many bikes, too many cars, too many things

        Comment


          #5
          Originally posted by 850 Combat View Post
          Did you pull the jets out and clean them all? Go through the carb cleaning links on BikeCliff's page.

          I think its still lean but not as bad.
          its a honda for one thing and I dont under stand the second line of what you wrote

          Comment


            #6
            nope i'm not sure if the jets are the correct size, i'm thinking not because of how it's running right now, and i haven't found a proper manual for the CM450 yet, altho i have one for a CB400-450 which is similar, but not quite the same.

            I totally don't want to keep the airbox because of the hassle of getting the carbs off. i did see that i can get a replacement K&N filter for it so maybe i'll try that first and if it doesn't make a difference then switch to pods. I figure if i'm messing around with the jetting anyway i can use some pods on it. I thought the difficulty of pods on the GSs was more with the engine and having 4 cylinders rather then the carbs, but now that i think about it it does make sense that the carbs could pull in different amounts of air from each other and all that.

            I did a somewhat quick job of cleaning the carbs because it was cold in my unheated garage, but really there was only a tiny bit of crud at the bottom of the float bowls, all of the jets where clear when i pulled them and all the passageways had spray coming through them fine. I thought when the engine revved and hung a bit it was because it was rich, having the excess fuel burning off...

            anyway i should go take it for a ride quickly tonight and feel how it runs.

            oh and the thought has crossed my mind of putting some slide carbs on it, it'd be not too expensive for only 2 of them... but then again this bike is supposed to be for my wife.

            Comment


              #7
              ok, so 850 combat was right, still lean. have to have full choke to rev it up fully on the road and there was a little bit of popping on decel

              has anybody used a "keyster carb kit?"



              Its probably easiest and chepest to get a full kit that restores the carbs to stock and my wife is anxious to get her bike on the road...

              Comment


                #8
                A carb is a carb, Kehien, Mikuni, Hitachi, Amal, they all are pretty much the same thing, CV's aren't that different from slide type when it comes to cleaning them. Yours sound like they still need cleaning.


                Originally posted by nisom512 View Post
                its a honda for one thing and I dont under stand the second line of what you wrote
                sigpic Too old, too many bikes, too many cars, too many things

                Comment


                  #9
                  If you are having lots of trouble getting the carbs back on ? You probably have shrunk, hardened boots. Not sure if they have an O ring like Suzuki's if they do change them..

                  Comment


                    #10
                    ok, so i pulled the carbs off again tonight and looked at the jets. I found a manual that tells me i need a 115 needle jet (main secondary in honda terms) and a 75 main (main primary) doesn't say anything about the pilot (slow jet) for my particular model. also i'm supposed to have a model # VB22J carb

                    What is in there is a 108 needle, 70 main and 38 pilot and a model # VB22MW, but i don't think the model number really matters, more the jets.
                    also the same manual said that an 83 CM 450 SC needs a 38 pilot, as well as the 85/86 450s, so i think the pilot jet is the correct size.

                    now do i need to buy a new main needle and air mix needle with the jets or would just the new jets be fine?

                    Comment


                      #11
                      ok new question.
                      I just cleaned my carbs again, switched out my main jets for 118s and 75s and then cleaned the air jet needle and set it back to the reccomended 2 1/4 turns, and fired up my bike to find it idling at probably 5000ish rpm or more (no tach), with some white smoke coming out of the pipes. I'm thinking the crazy high idle is an air leak from of my carb boots coming from the engine?
                      I do have hardened shrunk boots on this honda, i had them off this last time, they're the type with the metal backing and an o ring that bolt flush to the engine. I find it easier to put them on the carbs while the carbs are off of the engine then bolt them to the engine while on the carbs still...
                      just checking to see if my reasoning is correct?

                      Comment


                        #12
                        I restored a CM400A so I know the beast pretty well.

                        I would suspect the anti backfire diaphragms on the carb are stuck and full of goo. Each carb has one, about 25 mm in diameter. If they hang open or closed it screws up the idle. GS carbs don't have this problem.

                        The intake boots DO have o rings, they cost more than the GS boot rings but you should replace them. They are around 7 US dollars a ring.

                        These bikes need a proper airbox and a filter. There are two silver screens in the airbox. Do not toss them as they are flame arrestors. They prevent the air filter from catching fire in the event of a backfire.

                        The choke system is more like a car, it has plates that restrict air into the carbs. These are a pain in the butt to adjust because the fast idle cam seldom works right. It either does not pick up the engine speed or it hangs up and keeps the speed too high. Check the choke to make sure the plates close and open fully, and that the idle speed cam picks up the throttle and lets it go when off.

                        The Keister kits are OK, I used a pair on my carbs. They do not include the anti backfire diaphragms, they are 24 dollars each. Don't use ethanol in the bike, it ruins the anti backfire valves.

                        As for the boots, you know the deal. No leaks and properly installed.
                        1981 GS650G , all the bike you need
                        1980 GS1000G Power corrupts, and absolute power corrupts absolutely

                        Comment


                          #13
                          thanks for the info, i'll look at the manual that i have to try and figure out where the anti backfire diaphragms are. I know the importance of having a proper airbox and all that and as far as i can tell/i've seen from the manual its all there, even the mesh.
                          here's the thing that has me scratching my head tho is that it was idling before i replaced the jets and adjusted the air mix screws.
                          the choke plates work fine, fully open and close, i'm going to have to look up that idle speed cam and see where/what it is.

                          I'd go mess around with that bike right now but its at a garage that i'm renting about 10 min away, and i'm pooped for tonight. I just got back from pushing my GS from my apartment to the gas station and back... I didn't drain my carbs before winter or put fuel stabilizer in the carbs. I did a por 15 coating kit on my gas tank so i figured it wouldn't have gas in it anyway so it should be fine...

                          I think i might go get the stuff to try boiling my carbs in lemon juice, just to make sure everything is extra super clean.
                          Last edited by Guest; 04-15-2009, 11:42 PM.

                          Comment


                            #14
                            I have a CMX 450 with 23000 on her and just did the carbs for the first time. Had to readjust the idle after reassembly, it was a bit fast as well. Don't forget to check the valve adjustment while you are fussing with the old girl. Stock, clean and properly adjusted carbs will make it run quite surprising.
                            V
                            Gustov
                            80 GS 1100 LT, 83 1100 G "Scruffy"
                            81 GS 1000 G
                            79 GS 850 G
                            81 GS 850 L
                            83 GS 550 ES, 85 GS 550 ES
                            80 GS 550 L
                            86 450 Rebel, 70CL 70, Yamaha TTR125
                            2002 Honda 919
                            2004 Ural Gear up

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