Hey 5Twins, thank for the responses. This bump is almost unnoticeable, its on the very bottom surface, that contacts the white plastic washer, no bigger than the tip of a pencil, and only protrudes 1-2mm. Its really tiny, and theres only one, as opposed to the two bigger ones that must be aligned to get the snap ring in correctly. This is actually below those.
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Carb Jetting
- Thread starter 09classic650
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- carburetors jetting
OK, yes many spring loaded needles incorporate this bump or nub. It cants the needle at a slight angle in the slide. I think this is done so the needle will remain in contact with the side of the needle jet during operation at all times (at all lift positions). I think this stops the needle from shaking around and vibrating in the jet, giving a more consistent and metered flow.
ahhhh...makes sense. I kept hunting for a place for it to go, great explanation. Just took it to the end of the road and back, ran great, lugged it in second, and stood on it, and bike pulled out of it great, no bogging, or sputtering, pulls hard at full throttle. May end up adjusting something once I actually put some miles on it, out on the highway, but for right now seems perfect. Go figure, stock jetting, 135 main--27.5 Pilot, and needle in position 3. Pods, slightly restricted straight pipes. Thanks for the help guys.
One more tip ..... take a look at the carb top screws in your carb set photos from post #26. Note that most of the screws peek out a thread or 2 from the bottom of the holes (as they should). Yamaha was nice enough to use 2mm longer screws (16mm) where the butterfly shaped bracket attaches to the inner mounting holes so they reach all the way through. For some reason though, they cheaped out on the screw holding the throttle cable bracket and used a shorter 14mm screw (like where no brackets mount). This screw only catches by a couple threads and if you're in and out of your carbs a lot, it will strip eventually (DAHIK). Best to right Yamaha's wrong and substitute a longer screw there. Yours isn't a glitch. Every set I've seen is like this.
Ahhh...great tip. Yes, really obvious in that picture. Truth be told, I thought they were all the same length, and didn't put them in any particular place. I will take a look, and make sure I have them in the right place, as well as "righting the wrong" Have been tempted to replace these with allen head screws, as the phillips head tends to get beat up, after removing them 85 times. Hopefully, I won't be taking them apart much from here forward.....
Thanks for the tip.
Thanks for the tip.Finally got the bike registered, and have put about 40 miles on it. Seems to run worse the longer I ride it. Stock jetting, 135 main, needle clip middle position, 27.5 pilot. The last thing I changed was putting the needle in middle position. This is the longest I've run it continuous, all previous rides were maybe 1/2 mile. Seems to cut out every so often, and sputters either out of the carbs, but sounds more like it sputters from the exhaust. Warmed up, and idling it sputters from the exhaust, like putting your hand near the end of the exhaust it lets out a pffft every few seconds. Going down the road it just cuts out briefly, but doesn't die. Sitting at idle if I remove a plug wire it stays running, however it runs higher rpm with one compared to the other. Doesn't start easy compared to in the past. Always was one kick, two at the most, now its like 5-10 kicks, and it doesn't always want choke even if its cold. Do I have a needle valve sticking? Any ideas? Checked the timing again, and its on the F at idle, though I don't have a tach so I don't know exactly the rpm.
bloodthirstysystem
XS650 Addict
synchronize the carbs. i did mine when they were off, slide a piece of paper under the butterflies and adjust until they feel the same. this should get them close enough. you can do it running and pulling a plug wire and adjusting until they both idle at the same speed.
Lunatic
XS650 Enthusiast
Have you checked your plugs? I was getting similar symptoms when I was going through jetting my carbs and they were really fouled. Similar scenario with a lot of initial short trips.
I pulled one of them, but not the other. I will check them both. The one I pulled was a bit dark. I've attempted a basic sync with the dead cylinder, but it really doesn't want to run on one of the cylinders, really irratic, or just dies. I had a coil overheat badly during tuning, wondering if that could be going bad. This problem seems to be getting worse the more I run it, so almost makes me thing its electrical...but I could be way off. Thanks for the ideas....time to pull the plugs.
Pulled both plugs, didn't look too bad, but cleaned them up a little (maybe unacceptable, but lightly with wire brush) put them back in. Started it back up, and have popping and blue flame coming from the exhaust of the left cylinder. I did fuel it up today, is it possible I got a shot of bad gas, or would there be buildup of fuel in that cylinder from deadening the cylinder for brief periods?
bloodthirstysystem
XS650 Addict
when i tune one cylinder at a time i open the vacuum barb on the carb holder. (take off the hose for stock setup or cap if you don't use vacuum) this way the cylinder isn't pulling in gas when the plug wire isn't attached - no fouling.
sounds light it might be electrical though. you should replace the condensers if you haven't already. they go bad and are cheap..
mine burned out recently. on the road it was lurching, backfiring, cutting out. when i tried dead cylinder tuning it would die.. i replaced the condensers and it is perfect.
advance auto - 1965 ford f100 condenser is $5 and change. get two, make a bracket
sounds light it might be electrical though. you should replace the condensers if you haven't already. they go bad and are cheap..
mine burned out recently. on the road it was lurching, backfiring, cutting out. when i tried dead cylinder tuning it would die.. i replaced the condensers and it is perfect.
advance auto - 1965 ford f100 condenser is $5 and change. get two, make a bracket
Sounds just like what mine is doing. It has to sit for a couple of days as I'm at work. Good idea on the vacuum barb cap (I didn't do that....:/, but will next time) Initially it was just sputtering, or missing, but kept getting worse the more I road. I changed the main jet to a 140 thinking it was starving for fuel, but that didn't help, then I tried to sync the carbs, but it wouldn't really run with just one cylinder (one side would; the other would) Ran very irratic either way. I will retrace my steps on my next day off, reverse what I've done, and start over, perhaps with new plugs, and a new condenser. I haven't replaced the condenser, are they basically all the same, or is the 1965 Ford F100 the only alternative other than getting one from mikesxs? Thanks for the help.
bloodthirstysystem
XS650 Addict
you should have 2 condensers, they're just back to back, one wire in each, one for each coil. you could probably use any condenser, the f100 is the cheapest one and the wire is rated for 600v. i wouldn't use one that's smaller than the stock part
Interesting. I have one condenser tied into two coils. Scratching head on that one. I wonder why mine is like that? Wonder if that is contributing to my problem? I'll have to find the spec's and run a check on my coils, also.
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bloodthirstysystem
XS650 Addict
this is how it should be. the colors on the wires might be wrong, i can't remember if grey or orange is right side
If you overheated a coil it is probably dead now. Leaving a points ignition on with the engine not running will fry a coil. I just did that on the first points bike I had messed with in a long time.
bloodthirstysystem
XS650 Addict
how long did you have it on for? it must be able to be on for a little while, like having trouble starting or testing lights..
I overheated one badly, can't remember exactly how, but I could have fried an egg on it, but basically the bike was running decent with a little skipping, but something might be on its way out, whether it be the condenser or coil. I'll run some resistance checks this weekend. Just looked at condensers on mikes, and he says one condenser pack per engine. http://www.mikesxs.net/products-27.html#products ..hard to tell from the picture, maybe there are two condensers in the pack.
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