bladero1 Posted July 10, 2009 Report Share Posted July 10, 2009 Hi all I hope there is somebody out there who can help me, I have several TY 175's that I have had for about 10yrs now one is completely in bits and the other I have never had it running properly in all the time I have had it, it has plenty of compression, been de-coked, new reed valve, plug, points, condenser, crank seals,I have 3 carbs and have cleaned and tried them all. When I got the bike it took about 20 kicks to start it and it was very sluggish and wouldnt tick over, I progressed from this to the bike going into melt down which was a bit frightening, flat out and not being able to stop it, plug must have been glowing as taking cap off didnt help, panic panic saved by key on flywheel shearing, bike back in shed for a while. I have had a bulb on the points and set the timing as close as possible to what the book says, I am running it on 50-1 in the tank and the oil intake on the carb has been soldered up, my strimmer and hedge trimmer love 50-1 and have done for years.So here we go my latest problem is 5 or 6 kicks and it is started with a minute amount of choke and have to keep slighty pulling choke(revving engine) which wants to rev to 10000 revs, have to keep this up for a couple of mins with my bum wobbling and can then control via throttle , bike goes ok over mid revs but over runs, ie it still carries on running for 2-3 seconds after you have shut it down which makes wheelies a tad hard as you always end up running after it.I have reset the throttle needle to what the book says it should be and have cleaned out 3 carbs many times. So is it an air leak? The throttle closes ok in the carb.Can anyone please help me Thanks in advance John Quote Link to comment Share on other sites More sharing options...
feetupfun Posted July 11, 2009 Report Share Posted July 11, 2009 (edited) It sounds like the pilot jet or pilot stream path is blocked. You are probably getting overrun because it is going extreme lean when you close the throttle coming off load. Most people would not get to that point because of how annoying it is to ride a bike with a huge flat spot. Edited July 11, 2009 by feetupfun Quote Link to comment Share on other sites More sharing options...
dave dix Posted July 11, 2009 Report Share Posted July 11, 2009 Could well be the pilot jet or crankseal leaking air or air leak around the manifold Dave Quote Link to comment Share on other sites More sharing options...
steve Posted July 11, 2009 Report Share Posted July 11, 2009 Before going in too deep I'd re-check all the basics first. It does sound like carburation. You've tried 3 carbs - all the same. When you swapped them over did you use the same carb top & slide assy. (easier as you don't have to fiddle around trying to change the cable) If so the problem could be in this area. You've re-set the needle? Check you have the needle fitted properly (clip plate holding it down ok?). Are you putting the slide in correctly? For your bike to rev so hard for so long it must have been fed with fuel, air and sparks. Ok so when it's screaming so hard the carbon in the head starts to glow so even taking the cap of wouldn't stop it. But there must have been fuel and air getting in. HOW? - find out and you've sorted it! Quote Link to comment Share on other sites More sharing options...
bladero1 Posted July 11, 2009 Author Report Share Posted July 11, 2009 Hi Australia thanks for your reply your description of the flat spot is spot on, its low down and Im guessing i have to keep revving bike at about3-4ooo revs to keep it going sweet, what do you mean that it may be the pilot stream path? I have had a small plastic pipe on all the places that the petrol should flow and blown succesfully through. I was up your way with my family a couple of years ago on tour in my camper, very nice Kind regards John Quote Link to comment Share on other sites More sharing options...
bladero1 Posted July 11, 2009 Author Report Share Posted July 11, 2009 Hi steve thanks for your reply I have got over that problem now, my head was polished and had no carbon on it so must have been the plug glowing. When trying different carbs I have also changed the slider to no avail but not the top cap and the book says this should be properly tightened so will try different cap and let you know Thanks John Quote Link to comment Share on other sites More sharing options...
bladero1 Posted July 11, 2009 Author Report Share Posted July 11, 2009 Hi Dave thanks for your reply I would discount the crank seals as I have fitted new ones and didnt think old ones looked that bad or any signs of leaking, I have fitted them the correct way round. I will take off the inlet rubber and have a good look and let you know. Thanks Kind regards John Quote Link to comment Share on other sites More sharing options...
feetupfun Posted July 11, 2009 Report Share Posted July 11, 2009 Hi Australia thanks for your reply your description of the flat spot is spot on, its low down and Im guessing i have to keep revving bike at about3-4ooo revs to keep it going sweet, what do you mean that it may be the pilot stream path? I have had a small plastic pipe on all the places that the petrol should flow and blown succesfully through. I was up your way with my family a couple of years ago on tour in my camper, very nice Kind regards John Good to hear you liked your travels over here. I too had a great time travelling around, living in a 4WD wagon with rooftop tent for 13 months back in 1993/4. About your bike, it is very common to need to remove the pilot jet to clean the hole in it, as it has a very tiny hole which sometimes blocks solid. Even a partial blockage will give symptoms as you describe. If you put it up to a light, you will see if it is clear or not. The pilot stream path is a passsage for air and air/fuel mixture to flow through and goes from the inlet end of the carby and comes out two tiny holes where the slide touches the venturi floor, and there is a passage for fuel from the float bowl, that incorporates the pilot jet. The air screw also forms part of this passage and controls how much air flows through the passage. To clean out the passage, remove the air screw and spring, remove the pilot jet and blow with high pressure air through all the passages. Quote Link to comment Share on other sites More sharing options...
rosscoman Posted July 12, 2009 Report Share Posted July 12, 2009 hi bud on the carb there is a pipe outlet on the right hand side that was originally for the two stroke pipe to attache from the pump, just make sure its either connected or you have to block it up, draws air you see, Quote Link to comment Share on other sites More sharing options...
bladero1 Posted July 14, 2009 Author Report Share Posted July 14, 2009 Hi thanks for that, the pipe on right hand side has been solderd up for a long time now so no air goes in there. Quote Link to comment Share on other sites More sharing options...
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