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Hammerider

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About Hammerider

  • Rank
    TT Bronze Member

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  • Gender
    Male
  • Location
    Washington
  • Interests
    Off road riding (dual sport)
    Hunting
    Ham Radio
    Old vehicle restoration (motorcycles, pickup trucks)
  1. From all that Ive read then, that jetting you have should be fine for a baseline. Its something else.
  2. Well, honestly, I would look for another reason first, trouble shooting will really narrow things down for you. I try to remember the KISS method, because generally its the simple that has stumped me more often than not. Narrow it down one step at a time before you jump into the "I need to change...". One thing to keep in mind, especially with the jetting combo you listed, is that the bike probably ran just fine on that before, so what happened to make it do what it is doing now. Be methodical, be precise, and (at least in my case) double check. Consider what you are telling me, its hard to start, and wont idle. Yes, that screams carb issue, however there are ways to trick the bike into thinking the carb is normal and we should attack the problems carefully. So, hard to start, have you tried to verify if the choke is working? Have you tried starting fluid? Once again, cleaning the carb has bit me in the ass more times than I could count where some minor orifice was clogged, and no matter how many times I cleaned it the clog would not dislodge. Idling can be related, so that would be my focus. Other things that can affect it is more major issues, like leaking cases and bad reeds. Those need to be checked if you get to the point that you are positive its not a carb issue. As for 'starting fluid' Ive had good luck with a spray bottle of gas mix, spritz a little in the carb with the slide all open, then kick it over. Granted, its not gonna tell you much other than how easy it may be to start if it has a proper amount of fuel to fire on. Oh, have you id'd the carb yet? Have you checked on how the carb operates yet? There are some excellent tutorials about them that may help clarify whats happening when you start the motor. In this case, the pilot or slow jet is what operates for the starting and idle, as well as the choke, so those circuits would be where I would focus the most attention to.
  3. I found this site to be very helpful figuring out what carb I had. http://www.carbparts.com/keihin.html As for a rebuild kit, they have parts too, but other than the needle/seat I wouldnt think you would need much else to replace; well except the bowl gasket. However, Im at a loss as to why you would need a new idle screw? Is it missing? Assuming the carb is complete, my first plan of attack would be to completely disassemble the carb and clean it. Spray carb cleaner works in a lot of cases, but worse case you may have to soak it in a bath of carb cleaner, sonic cleaner, or some such to be sure to clear out those small orifices of gunk. I had one bike years ago that took a half dozen soaks, and a small wire to clear an obstruction that was causing a bad idle. (I dont typically suggest sticking anything through a carb orifice, I just ran out of options). While you have the carb apart take notes to the float height, the slide and needle, and the jetting. Once all that is clear, and you are confident it is completely clean, then you can try to set the slow jet air adjustment, and idle to see if that fixes your problem.
  4. Im going to do that; I was just hoping someone had experience with a baseline setting to start with. I have a hard time thinking a 70 slow jet is normal, especially sitting next to a 158 main. But Im also not opposed to dialing it in better, I just wasnt sure what or where I wanted to start with for jets. It'll get a bit expensive if I get one of each size, and time consuming if I order only one at a time, especially when I need only one set, and would be happier with only a few extra sitting on the shelf.
  5. I will definitely look into the reeds then, thanks for the info. As for the "whack the throttle" method, Im not familiar with that term. I get the impression it is a crack open the throttle quickly type operation? Yeah, I didnt adjust it yet, we are going to finish cleaning the carb tonight and get it back on the bike and see what it (the air screw) does.
  6. Yeah, I figure that too, lol; but Im not new to two-strokes, although its been a LONG time since Ive delt with carb tuning; and this problem screams carb issue. When I took it apart to clean the internals were pristine with absolutely no gunk in the bowl and no varnish to be seen. You could tell the carb hasnt been off the bike in a while too, so at least that is promising. That and I rode the tar out of it and find it to be a solid bike, other than normal wear and tear, and the motor sounded tight. I do believe the main jet is good, maybe a little big but performance suggests its within usable limits, especially since its not a race bike. Its just that that 70 slow jet is what has me rattled compared to the off idle bog that is so bad you have to really baby it to get the bike to move, but once you open it up and keep it up (probably 1/2 or more throttle at all times) it screams along just fine.
  7. Yeah, thats what I mean. One, they dont list the 1993 Yamaha YZ125, nor do they list the jetting for a different carb from stock. From what I can tell, the '93 came with a Mikuni carb stock, this is a Keihin 34mm PJ carb and so far I cannot seem to find any information that seems to be consistent with any 125 two-stroke with a PJ carb configuration. With the symptoms this bike has, it suggests that the slow jet is lean, however I thought the larger the number on a Keihin jet is a larger orifice which I believe should make for a rich condition. I suppose the current set up is fine and I still have a clogged port somewhere; Been down that road before. Im hoping to find someone familiar with the PJ carbs and get a base configuration; I guess it boils down to not wanting to buy a dozen jets if I dont need to. as for the rest; I was told its a new top end. Not sure about the silencer or reeds; but I would suspect if the top end was done the repair center would have addressed that at the time too. With the way it runs, I do feel confident in thinking most of that is in fair condition.
  8. So, I'm sure this has been discussed in depth somewhere; however I'm having a hard time finding out. Here's my story, just bought a '93 YZ125 for my son and I believe the jetting is horrifically unbalanced, or set up for something specific. None the less the thing has a horrific bog off idle and it takes a bit to get it to move, but once you get going and keep the throttle up high, it scoots right along. General information, we are at about 1300ft, dry conditions/desert living, stock YZ with the exception that the carb is a Keihin PJ with an R1470N needle, 70 slow jet, and a 158 main. So far I have been able to determine the slow jet is significantly big, but I cannot seem to find info on a baseline config for this set up. thanks for all your help.
  9. Hammerider

    Washington SB 5141 Hope this one passes

    Allows motorcycles to carefully progress through intersections if your scoot doesn't trigger the signal after one cycle in a controlled signal intersection. This happens to me a lot, with the dual sports, the Goldwing seems to activate them OK. But I've had to sit at lights sometimes untill a car pulls up behind me and triggers it.
  10. Hammerider

    Best mpg 4x4 vehicle

    1991 Suzuki sidekick, tows 2 bikes in a trailer fairly easily, 30mpg empty, towing about 23/25mpg depending on hills.
  11. You will probably have to change the differential ratio also, as automatics run a high ratio as a rule, or if it's a 4x4 you can change the transfer case ratio, easier than both differentials.
  12. I have towed my little Scamp trailer with extended hitch bar for 23 years, several times with a chev luv diesel, many times with assorted Nissan Frontiers all with tailgate down for bikes, no problem as long as it is designed to handle the load properly.
  13. Before I retired I always bought frontier 4x4 xcabs w/v6 for commuting, every 5/7 years, ALWAYS bought w/5spd trans, cause I hauled scoots and small camper to the mountains for riding, the last one I ordered w/5spd the salesman told me the automatic was rated for heavier towing, I checked the owners manual, he was correct, the auto was rated almost 1000 lbs heavier for towing. the rules change as time progresses........
  14. Hammerider

    Interesting to see how this plays out..........

    Well there partner I am 70 years old, been riding motorcycle since 1958, lived through no helmet law, helmet law, helmet law repealed as unconstitutional, rewritten and reinstated, I AM STILL HERE, think I wear a helmet?? yes, I do not like to be told by "MY" govt. that I have to..........
  15. Helmet Law again, hope it gets repealed, we do NOT need Mommy Govt. Telling us to wear them!!! http://www.thenewstribune.com/2013/01/31/2456172/motorcyclists-push-for-repeal.html
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