hippiedreads
XS650 Enthusiast
Ah okay that helps clarify greatly. Even though I'm using the stock 45 pilot jet you'd go down to a 40?
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74 Running Super Rich
- Thread starter hippiedreads
- Start date
Jets come in 2.5 number increments so the next smaller size would be a 42.5. If you're checking your plugs immediately after starting with the choke, they will be black. Using the choke blackens them. It will take a good ride of a few miles to burn them clean again. I recently had to clean my plugs because of this. I did too many cold choke starts and short rides in a row and my plugs began to foul. I was never riding the bike long enough to burn them clean.
hippiedreads
XS650 Enthusiast
5twins, I've seen many people on here say jump by two sizes because one size will only make a slight difference. So from your personal perspective would you try the 42.5 instead of the 40? I am aware that the choke will blacken plugs and after a few starts its not needed so I just start it with the choke off. I will keep that in mind for the future though as I've got quite the road to get her running down the road ahead of me.
And wish I could tell you guys I've had more time this weekend to work on it but full time student and full time and bartend on weekends hasn't allowed me much personal time. Tomorrow morning before class I'm getting up early to get a couple hours in the garage and I'll keep everyone posted.
And wish I could tell you guys I've had more time this weekend to work on it but full time student and full time and bartend on weekends hasn't allowed me much personal time. Tomorrow morning before class I'm getting up early to get a couple hours in the garage and I'll keep everyone posted.
Well, if a certain bike generally needs a large jump in jet sizes when tuning for mods, like say 8 or 10, then sure, going up 2 at a time would be fine. But the 650 isn't like that. It usually only needs 1 or 2, or maybe 3 sizes different than stock, so just one size can make a real difference. But you have a rather odd case here. Usually we're jetting up for mods. You seem to need to jet down. That's strange. Did you check the air jet in the intake bell? The one on the right supplies the idle circuit .....
hippiedreads
XS650 Enthusiast
Yup, spray through the pilot hole side multiple times checking to make sure all 4 holes are shooting out carb cleaner. I seem to have the right cylinder dialed in okay but the left one is fouling still. One spark plug is a little weaker than the other (will buy new plugs later today) so I swapped cylinders with them. And still get about the same results, clean plugs put them in hook bike up and run at idle (somewhere between 1000-1400 rpm, still playing with everything) and after about 1-2 mins idling (no choke) I pull the left plug and it looks like this. Also the left cylinder has the stronger sparking plug in it for this picture. I really don't want to change the pilot jet because I think I'll just be compensating for another problem.
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No, I'm not talking about the pilot jet and it's passageways into the main bore, I'm talking about the air jet that supplies air to the pilot jet. If it's plugged, you'll get no air to mix with the pilot jet's fuel. Air enters through the holes circled above and comes out the air feeds on either side of the needle jet on the carb bottom. See the 1st pic in post 10.
The right hole pictured above feeds the pilot jet. The left hole feeds the main jet.
The right hole pictured above feeds the pilot jet. The left hole feeds the main jet.
hippiedreads
XS650 Enthusiast
Sorry I was confused with that picture you sent, I thought you were asking it that cleared our and yes it is. As for the air jet in the bowl its clean and clear as of two days ago, I didn't not clean it again this morning before work and class but I guess it is possible that something got in it and clogged it up or I didn't get all the gunk cleaned out of it even though I've cleaned the damn thing a half a dozen times.
I'm out of class at 9 then back to the garage I'll double check the air passages again.
I'm out of class at 9 then back to the garage I'll double check the air passages again.
Have a look thru the carb guide, and ensure that you've got the correct pilot jets for your bowl type, i.e., BS30/96 vs VM22/210. And, for that matter, the correct bowls for the carb bodies...
thats a good suggestion 2M I didn't think of that. This over rich idle is a bit strange given the info we have but the wrong pilot would certainly cause it.
Also Hippie the engine isn't idling at 1000rpm and above...... it should be idling at around 850-950rpm 1500rpm is way too high and the vacuum from the engine will presumably be lifting the diaphrams and drawing fuel from the needle jet.
I'm wondering if you have set your idle too high or your butterfly valves are out of sync or not returning completely to their stops .
It might be helpful to hear and watch a video of the bike idling.
The idle speed spec for these bikes is 1200 RPM. Yes, 1500 is too high, but 850-950 is too low. I tried running a lower idle speed when I 1st got my 650. All my other bikes used a lower speed and the 650 just sounded too fast at 1200. The bike would randomly stall at stops using the lower setting. Setting it to spec cured that. I've grown used to the 1100-1200 RPM idle now and it just sounds normal. I feel it is required. Besides the stalling, at that lower setting you will have little, if any, charging going on and less oil circulation.
hippiedreads
XS650 Enthusiast
I mean I guess I should check the jets out, all I did was pull the old main jet and pilot jet and replaced them with jets I got at a local dealership. Brought the old ones in and matched them with the ones that matched up. Is there an easy way to tell the difference between jets? The only indicator I could see on the new ones were the 127.5 on the main jets head and 45 pilot on the neck. None of the other jets were touched because it's a low miles bike before being torn apart and put into boxes and all other jets a securely in place and everything seems to operate smoothly.
Pulled the BP7ES plugs last night and the ngk resistant boots put on stock boots and the BP7RES that came with the pma pamco set up and now it won't even run. I ordered new BP7ES plugs last night and will be in hopefully tomorrow but maybe Friday so until then I won't be able to get a good video of her running.
I pulled a picture offline that is the same bowl type as mine and checks out. Attached is the pic and correct me if I'm wrong but it's the same bowl set up as all the old XS1,2 and early TX/XS models.
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hippiedreads
XS650 Enthusiast
However maybe someone can explain this to me, with this current set up of stock spark plug boots and the resistant plugs I can't get it to even hit. When I pull the left plug and ground it to the motor the right side will try to fire. When I pull the right side and leave the left side in the cylinder then the right one will fire. If I have both in the cylinder neither will fire. Both have a good solid big bright blue spark outside of the cylinder. I have a video of this I took on my iPhone but when I upload it it kicks back an error saying the video has no extension. Does anyone know how to get past this to post the video?
Note: battery sucks because I've filled and drained it a million times to get this sucker running. After charging it and getting the batter to 12.9V I take it off the charger turn the bike on and use the starter motor to turn the engine over and get nothing. Timing light shows I'm getting a spark. Without turning the key or killswitch off I'll pull one plug at a time and ground it to the motor and check my spark color. At this point whichever cylinder still has the spark plug in it will hit one time each cycle. So left hit nothing right left hit nothing right left hit nothing right. And vice versa of the right plug is in and the left plug is out. I'm chalking it up to being different plugs and hoping that getting new BP7ES will fix it. Just seems really odd to me that they will fire individually with one or but neither will hit with both in.
Note: battery sucks because I've filled and drained it a million times to get this sucker running. After charging it and getting the batter to 12.9V I take it off the charger turn the bike on and use the starter motor to turn the engine over and get nothing. Timing light shows I'm getting a spark. Without turning the key or killswitch off I'll pull one plug at a time and ground it to the motor and check my spark color. At this point whichever cylinder still has the spark plug in it will hit one time each cycle. So left hit nothing right left hit nothing right left hit nothing right. And vice versa of the right plug is in and the left plug is out. I'm chalking it up to being different plugs and hoping that getting new BP7ES will fix it. Just seems really odd to me that they will fire individually with one or but neither will hit with both in.
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Hey hippiedreads, not familiar with the apple world but I expect the process would be the same.
Create a YouTube account. Upload the video to that and then copy and paste the video URL into your post.
Video will then appear here.
Create a YouTube account. Upload the video to that and then copy and paste the video URL into your post.
Video will then appear here.
hippiedreads
XS650 Enthusiast
Thank you
The original factory spark plug caps are a higher resistance (like 8K or 9K ohms) than the NGK 5K ohm caps. You also stuck resistor plugs in there with them. That could be too much resistance in the circuit and may be why it's not firing. You only want one instance of resistance in the circuit, plug or plug cap, but not both.
Your mains are probably matched up OK, they're pretty easy. The pilots may not be though. The 2 types used in the 650 carbs look pretty much the same from the outside at a glance and will physically interchange, but they don't flow the same. And the float bowls differ depending on which type is called for. Your float bowls look correct for your carbs, yours use the BS30/96 type pilots and bowls .....
Here's how to I.D. the pilot jets by the location of the metering orifice (top or bottom) .....
Your mains are probably matched up OK, they're pretty easy. The pilots may not be though. The 2 types used in the 650 carbs look pretty much the same from the outside at a glance and will physically interchange, but they don't flow the same. And the float bowls differ depending on which type is called for. Your float bowls look correct for your carbs, yours use the BS30/96 type pilots and bowls .....
Here's how to I.D. the pilot jets by the location of the metering orifice (top or bottom) .....
where are you grounding the plugs when they are out of the cylinder head ?
Sounds like you might have a poor ground connection between the frame and the engine . Try running a jump lead between a clean point on the frame and the engine and see if your spark improves .
The fact that the cylinder is not firing when the spark plug is fitted might not be down to the ignition spark but something else. If you buy a spark plug tester for a couple of dollars you can check your spark safely whilst starting and running the engine
sorry to disagree 5T but If your engine is in a good state of tune like mine it should idle happily and stable at 850 -950rpm .I never get random stalls at traffic lights or on deacceleration but to be honest we don't have a lot of them out here in the countryside. The difference in oil flow between 950rpm and 1200 rpm is negligable and Yamaha designed the engine to have more than sufficient oil flow with an adequate margin.
Anyway the important point that I made which nobody else picked up previously is Hippies engine idle is set way too high to adjust correctly.
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hippiedreads
XS650 Enthusiast
Okay, yes I understand that 1500 is way to high for idle but I've been doing almost all the work around 1200 rpm which is also what my manual says is correct so if that's too high idk where to go because 1000 rpm and the sucker is clearly dieing out because of lack of fuel/air.
Peanut, the intention has been to get one but I always just saying eh screw it and pulling the plug. I will run a ground wire right to the plugs after class tonight and see if that helps.
Here is a video of what I'm talking about with these new plugs. Also I'm switching back to the BP7ES plugs as soon as they arrive and they were not giving me this problem. I'm just wondering if this could be a sign for something else.
Peanut, the intention has been to get one but I always just saying eh screw it and pulling the plug. I will run a ground wire right to the plugs after class tonight and see if that helps.
Here is a video of what I'm talking about with these new plugs. Also I'm switching back to the BP7ES plugs as soon as they arrive and they were not giving me this problem. I'm just wondering if this could be a sign for something else.
I see in your video you're running the pleated pods. They don't work right on CV carbs and may be contributing to your troubles. Also many have an inner lip on the mounting flange that can partially block the air ports .....
I would run some tests with them removed.
I would run some tests with them removed.
hippiedreads
XS650 Enthusiast
I know the pods aren't great for the CV carbs thanks to many post on here about it but that is all I have for the time being as the stockers were nasty with stink bugs. I've been running the bike with and without the filters and I haven't seen a difference with or without the pods. I just happened to have them on when taking the video. I was unaware that the stock plug caps were resistant! Someone actually told me to run the resistant plugs on the original boots because they were non resistant. Guess I could have used my multi-meter to test it rather than trust someone from a shop (duhhh, always fact check and not presume information is correct). So that is actually a lot of help in itself. I get out of class around 6 tonight then back at it. Ill pay even closer attention to how the filter compares to no filter.
If I cant come up with anything tonight, I am going to hang up this problem until I get new spark plugs and tackle other things with the bike. Expected delivery date of plugs is Friday of this week to Wednesday of next week.
Does anyone have any thoughts on why one cylinder will fire alone with only one plug in but both cylinders won't fire when both plugs are in?
