k91 Posted March 23, 2008 Share Posted March 23, 2008 I was out on a test ride yesterday and the bike started bogging and barely kept running. I checked the plugs and they are both black which I figure makes sense since the airfilters have been soaked with fuel many times. So I pull the filters out and run again. Much better. But I check the plugs again and I'm lean of course. I have a set of pod filters to put on and I want to replace the stock mufflers. Any thoughts on how many sizes to go up? Maybe 2 sizes to start? Link to comment Share on other sites More sharing options...
Moderator drewpy Posted March 23, 2008 Moderator Share Posted March 23, 2008 I was out on a test ride yesterday and the bike started bogging and barely kept running. I checked the plugs and they are both black which I figure makes sense since the airfilters have been soaked with fuel many times. So I pull the filters out and run again. Much better. But I check the plugs again and I'm lean of course. I have a set of pod filters to put on and I want to replace the stock mufflers. Any thoughts on how many sizes to go up? Maybe 2 sizes to start? try raising the main needles and see what happens there? Link to comment Share on other sites More sharing options...
xs360 Posted March 23, 2008 Share Posted March 23, 2008 this might help as a rough guide , my 1976 kawasaki z750 twin runs mikuni bs38 carbs , the main jets were increased from 125 to 140 , and the pilot jet from 45 to 50 . you might also need a small crankcase filter ... but if you remove the air filter there should be provision for another tool box ? it's my coffee pot mod !! sure it's the wrong bike but you'll see what i mean !! Link to comment Share on other sites More sharing options...
k91 Posted March 25, 2008 Author Share Posted March 25, 2008 drewpy - You mean change the location of the clip? Do I move it towards the tip of the needle more or back towards the top of the diaphragm? I think now the clips are on the 3rd ring back from the tip of the needle. xs360 - The pods I bought say they are for 1980 XS400s but they were too small to fit over the carbs but fit perfectly on the intake tubes. So I didn't really gain any extra space. I think the mains are 132.5 stock right but what are the pilots? I was thinking about the Part #07-0041 taper tip mufflers from www.mikesxs.com to replace my blown out stock cans. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted March 25, 2008 Moderator Share Posted March 25, 2008 drewpy - You mean change the location of the clip? Do I move it towards the tip of the needle more or back towards the top of the diaphragm? I think now the clips are on the 3rd ring back from the tip of the needle. xs360 - The pods I bought say they are for 1980 XS400s but they were too small to fit over the carbs but fit perfectly on the intake tubes. So I didn't really gain any extra space. I think the mains are 132.5 stock right but what are the pilots? I was thinking about the Part #07-0041 taper tip mufflers from www.mikesxs.com to replace my blown out stock cans. raising the needle (lowering the clip will let more fuel in to compensate for the extra air) its a case of suck it and see! Link to comment Share on other sites More sharing options...
k91 Posted April 10, 2008 Author Share Posted April 10, 2008 Anybody know what size the pilot jets are on a 1980 XS400? I got it to run more consistently after replacing the faulty coil so I'm looking to place my order soon. Oh and the carbs don't have the movable clip on the needles its the 79 that does. Link to comment Share on other sites More sharing options...
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