The Journey of a wrench and his first motorcycle

Running non-stock intakes or exhausts will cause most issues for tuning. Also with your year carbs the idle mix screws tips tend to break off in the carbs making tuning impossible.
 
Setting the timing by static method is only the first step. This will only get you in the ballpark of where the timing should be. Next, you need a timing light to get the timing perfect and then you can get both cylinders firing when they should be. I forget how the points plate works, but I thought it was that the plate controls the right side and the left side is adjustable once the plate/right side is set?

You cannot continue tuning until you set timing with a light. Which also brings up the possibility that you probably didnt check valve lash either.
 
Running non-stock intakes or exhausts will cause most issues for tuning. Also with your year carbs the idle mix screws tips tend to break off in the carbs making tuning impossible.

Thanks xschris I appreciate the wisdom. The plugs arn't nearly as lean looking after upping the pilots but its starting to look like my midrange is a little rich going to put another tank of gas worth of miles on the current settings and check the overall color again. Idle mix screws are intact and the passage ways are clear.

Setting the timing by static method is only the first step. This will only get you in the ballpark of where the timing should be. Next, you need a timing light to get the timing perfect and then you can get both cylinders firing when they should be. I forget how the points plate works, but I thought it was that the plate controls the right side and the left side is adjustable once the plate/right side is set?

You cannot continue tuning until you set timing with a light. Which also brings up the possibility that you probably didnt check valve lash either.

As per the manual i believe what you refer to as valve lash I know as valve clearances I re-check or adjust mine every 6 months or 4000 miles setting mine to a loose slip fit 0.08mm inlet and a loose slip fit 0.16mm exhaust. Honestly I do mine on a shorter time frame since i regularly check points gap and timing and if i have a "cold" engine I'm going to take 15mins to double check clearances. Also per manual the complete contact breaker plate effects the left cylinder and "separate smaller base plate" effects the right cylinder. If i lived near you NewHavenMike, would you show me how to dynamically time my engine or would you tell me to kick rocks? Whats your views on the youth? Are you convinced yet that they are our future? Help teach and guide is my moto. The advice on the air leak was sound, but your other comments on how I'm trying to hard, i don't know what I'm doing, I'm skipping important steps and that I'm getting frustrated easily isn't really necessary. If all the mean in the world hadn't hardend my skins years ago your replys read like the only thing i should be doing is writing a craigslist add to sell my bike. I digress. It sounds like you don't have points ignition anymore but in another universe i bet we could go into a feeler gauge technique session and learn something from each over. I'm also going to continue tuning as my timing is set up according to the manual, which is good enough for Yamaha and is good enough for my beater introduction to motorcycle engines. I'll upload some recordings of it at idle and i could use your wisdom on what you hear.
 
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Hey dude, i am the youth too. If you lived closer id be more than happy to bring out some of my tools. Itd actually be nice to have a friend with the same bike near me...Its just that these first steps are very important. Im not trying to put you down, my XS360 is my first bike and i went through a ton of bugs with the carb and ignition before i got it decent. If you upload a clip of the bike running, someone on here will confirm that your timing is off, if it is. I had a lot of trouble with my points ignition and didnt want to deal with it anymore so i changed it out. That technology was outdated in the 70s. Owning one of these bikes will make you a mechanic thats for sure.
 
I actually feel pretty stupid asking for help, then getting all defensive. I do have a stroboscope? "Timing light" but the bikes been hacked up pretty bad and im missing the centre stand and probably the mounts to attach on. Need to get me a proper lift.
 
I actually feel pretty stupid asking for help, then getting all defensive. I do have a stroboscope? "Timing light" but the bikes been hacked up pretty bad and im missing the centre stand and probably the mounts to attach on. Need to get me a proper lift.

Look at your frame if the mounts are there I have a center stand somewhere. Yours for shipping if interested.

Mine only has the side stand and wish I had a center stand.
 
I removed my center stand and now use it as needed.

I suppose if you could lean the bike on a wall on the right side and put blocks of wood on both ends of the wheels, checking the timing could be done.

You need to remove the side cover to get to the timing marks and also have access to the points.

When I first got my bike going after a whole new top end build, I went crazy. I timed the bike statically thinking it would be OK. The bike would not run unless I was revving over like 4k. I hooked up the timing light and found out that I was somewhere near 10 degrees ATDC on both cylinders. I changed it and the bike ran great..

Then I rode it around and the points needed more adjustment and then wouldnt stay still and one cylinder was firing too late. I was still riding it just fine though. I pulled up to my brother to show him my newly finished/registered bike... He immediately told me something was up with the timing. I checked it later and sure enough, one cylinder was still too retarded. I fixed it and the bike was a whole different machine afterward.

Then I got the Pamco and will never go back to points again. I get a much better spark now and its easier and more accurate to tune.
 
I agree on the Pamco ignition. Have an older unit on mine and love it. The new ones look even better.
 

lol try and post a video of the idle and all i do is yap over the duration of the video
 
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Are you running stock exhaust on it? Saw one pipe but the plate was in the way of the other one........
 
Im pretty certain they are headers that were cut right at the start of the muffler. Or if they made headers that didn't get welded to mufflers at the factory, i got a pair on ebay. Then i put the original slip ons back. This was an attempt to get it back to how i got it. Which i remember running well before i thrashed the original headers not sure how *i suspect running lean after i downsized the main when i knew a little less, the headers splintered down the length from sustained 7k+ rpm on a fast ass ride i took for a couple hours 75mph +* and replaced them with NOS 2 too 2 with an h pipe under the engine. This dramatically changed my jets due to the restricted exhaust flow. but because there are no mounts left for passenger pegs or mufflers the h pipe slowly developed a crack from vibration. So i replaced with new headers and the old slip ons. Rejetted and have been kinda leaving it alone. I think my slightly high idle needs a 145 pilot up from 142.5 due to slight leaness and using performance and feel i think i need a 145 main, down from a 147 since it seems to rip around 6k to redline when cold then loses a little "pull" after about 30+ miles when its really warm.
 
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Still keeping the machine rolling. Thought i would ask if the sages hear any subtle clues and looking for a pointer on the idle hang. Is it normal or is it hesitation. Going to make another manometer very soon if not tonight and double check the balance.
 
Idle hang is either cable-related (hanging cable,ill-adjusted tension at the handle,rusty or ill-adjusted return spring)...or an air leak at the intake
 
That seems to be my take on it. I know I use to drive it that way, sometimes I would adjust the idle at stop lights. Most of the time it would drop as soon as you drop it into 2nd gear, and slowing down a little bit more (engine braking). I think the rule of thumb I used the most, is "sometimes the Italian tune up, is best." meaning to give it a try. (safely).
 
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