luvmy40

New plugs and a carb sync.

Yep, My manual matches Steven's. Bongobobny, No YICS chamber. It was cracked so I just took it off and capped the ports. It is possible that the caps have developed leaks since I last checked, so I'll check that again as well. I got new plugs today and will run another comp test and install the plugs gaped at .032". I had been setting the gap to factor spec of .036". I do alternate running Lucas fuel additive, Sea Foam and Star Tron enzyme. Not every tank but fairly regularly. My current tank is treated with the Lucas. I'll try to dig up a bore scope and see if I can get a look at the piston heads and valves.

I'll snag new plugs tomorrow as well. Any befit in going up a point in heat?

Yes, The float levels have been checked and are good. The compression spec from the service manual is 128-156 psi. It would appear that I am quite high. I will run another test ASAP just to make sure I wasn't reading the gauge wrong. I have been told since I ran that test that you should only cycle 4 times and I'm sure I chugged it much more than that. That may account for the high readings.

Here are the compression test results from 3/9/2018 Compression test results: #1 190psi #2 185psi #3 190psi #3 190psi #3 190psi #3 190psi #4 180psi I ran #3 multiple times as that cylinder was giving me grief at the time. The only change to the carbs other than new OEM gaskets and o rings are Skydoc's needle shims. No other modifications. I'm not sure what you mean when you say you are not impressed with the plugs. The plugs are new this season and have approx. 1700 miles on them. I checked for vacuum leaks around the same time I ran the comp test but I'll do it again tomorrow. Didn't find any leaks then. The main diaphragms and the coast diaphragms looked good from a visual inspection. I stretched them looking for pin holes and found none. If the acceleration was much more crisp, I'd have whip lash.

I just swapped the needle shims for Skydoc's shim set that is supposed to stop the popping.

Tried to get the popping on video. And when I got back from that ride she was stumbling at idle again.

I got some pics of the spark plugs and I decided to play around and do some vid clips. The popping and stumble doesn't come through in the audio as well as I'd like but here goes. The plugs all look way lean to me. N0.1 No.2 No.3 N0.4 I re tuned the pilot mix to best highest vac and ended up enriching all 4 cylinders a good bit. After bI got them tweaked to the highest vac. I opened them up 1/4 turn further, Then synchronized. Here's the result.

I used Skydoc's needle shims when I rebuilt the carbs. I have had the popping tuned out almost completely but it was definitely a rich mix. I'm going to pull the plugs later and see what they tell me. Right now the pilot circuits are tuned to highest vac reading then synced at 1000 rpm.

I mentioned this in another thread started by oldfailthful but didn't want to clutter his line up, so... I have been working on getting my pilot mixture and synchronization perfect. I've gone several different routes on the pilot mix. I first went with a color tune which I have used for years with great success on my XJ bikes. I didn't get the same level of feedback with the Venture so my results were only so-so. I then just tuned by ear with very poor results. So back to the color tune. Then I tuned to vacuum. BTW, My sync is always tight. That's never a problem. So here's the deal. No matter how I set the pilot circuits, I always either have a lot of popping on deceleration or sluggish throttle response off idle. Right now i'm getting both. She pops like crazy on decel and takes forever to warm up. Once warm, the throttle response is good. She's also developed a lope at idle. An intermittent "miss". I haven't investigated the miss as yet. Ok, so here's the strange thing. Tuned as is with the popping, slow warm up and lope at idle, I'm getting the best fuel economy I have gotten to date. My last tank ran 39.5 MPG as close as I can figure by filling to the same level in the neck visually. Up till now I'd been getting 33-35 mpg and before the carb rebuild I was getting 28-29 mpg. On a possibly related note; My voltage meter is showing 12v at idle and sits solid at 14v while riding but when not rolling, in neutral or with the clutch in at a light it will not rise above 12v at any rpm. This is a new bug. I just noticed a couple days ago and it went away for a short time but is back now. :confused::confused: ETA. She pulls strong once warmed up. Plenty of power and no detectable miss at speed.

oldfaithful, No I haven't dug into it at all yet. Cowpuc, I just posted up in another thread that I saw a sluggish rise to 14V for the first time since I have had The Beast. It only happened once but it took about 30 sends to get from 12 to 14V from a stop at idle when I took off. Then it was all good again.

My '83 has an intermittent stumble at idle. I've got her dialed down a bit low, about 950rpm+/- and I don't know if it's one specific cylinder or not.

DragonRider, If you do not already know about it, check out xjbikes.com another great forum dedicated to the Yamaha XJ series. One of the members(probably the owner) is a spectacular source of NOS and aftermarket parts for the XJ bikes. If chacal doesn't have it, it's not available.

Yes, That is exactly what this fix takes care of. My shouldered bolt was tight, just the jamb nut was loose, but I had an inch and a half, give or take of up and down play in the side stand when on the center stand. The Beast was leaning way too much when on the side stand. There's a thread thad has pics of the repair somewhere. But it really is simple. I used grade 8, 1/2" hardware. The thread I mentioned used M12-1.25 hardened parts. The 1/2" stuff requires a little more drilling than the M12 but I think it tightens things up better. I used a 1/2"-13x2" lag bolt and two 1/2"-13 nuts. I couldn't find a 1/2"-13 jamb nut so I just cut a regular nut in half with a right angle grinder and cut off wheel. Try to get a lag just a bit shorter than the shoulder on the OEM bolt. The lag should be long enough to extend through the top ear of the side stand, through the mounting tab and into the bottom ear but not through the bottom ear. Mine was just barely to the bottom ear. Drill the holes in the ears on side stand and the hole in the mounting tab out to 1/2". This drilled very easily with a cordless drill on low speed as you are not removing much stock at all. With the M12 hardware, I believe you only need to drill out the threads on the bottom ear of the side stand. I don't remember what size drill was recommended. Stick the bolt through the side stand and thread the nut and jamb nut on finger tight. Mark the length of the bolt flush with the jamb nut and cut it off. Remount the side stand on the bike. Tighten the first nut up until there is little to no up and down movement of the side stand but it still moves easily. Then lock it up with the jamb nut. A little medium strength LocTite wouldn't hurt but I didn't bother with it since that's exactly what the jamb nut is for.

I, and a couple local guys who ride Gen 2 bikes use Rotella T5 with Lucas additive. Works well and the Lucas smooths the shifting out immensely.

How's it going on the Maxim? Are the controls going to work for you? They were for the XJ750 originally.

Just to clarify. The voltage has always dropped to around 12V at idle. It just always picked back up to 14 as soon as the rpms were back up over 1500 or so. That fairly typical of motorcycle charging systems. This one time, it took a while to get back up to 14V. I know the Gen1 MK1 had an issue with the stator not getting enough oil for cooling. I'd just assumed(I know!) that at 130K mi. any problems would have already been dealt with or would have been obvious from the start.

I'll take a look at them tomorrow but I do keep a close eye on that kind of stuff and they were fine before I left for MD, about 1K mi. ago.

I noticed something I'd not noticed before while out on a ride this afternoon. While stopped at a traffic light my voltage was down at 12V. This in it's self is not odd. I've got the idle a little low, around 950 rpm+/- and the volt meter has always been solid at 14V when over 1500 rpm. I gave her a little throttle while still stopped, up to about 1800 rpm and the voltmeter didn't budge. When I took off from the light, I watched the voltmeter and it took a long time, maybe 30 seconds to come up to 14V. The next time I stopped, everything was back to normal. 12V at idle, 14V as soon as I took off. I haven't checked to see if the stator mod has been done or if she has an after market stator. There hasn't been any need as of yet. What exactly am I looking for on the stator cooling mod? Is there any way to determine if the stator is original or aftermarket? Does the simptom above sound like a stator or rectifier issue? Or, is it just a normal thing that I never noticed before? Thanks in advance for any input!

I love when I can help out another rider in need. Kris and I were out for a short CTFW session this afternoon. We'd been randomly running the back roads in our rural area for a couple hours and were headed home when I saw the tail light go out on a bike sitting at a traffic light for the freeway on ramp. The rider and his passenger pushed the scooter off to the side of the road as we went by. I spun around at the next light and came back to them, a younger guy and his GF/Wife on a beautiful older yellow Moto Guzzi bobber. When I asked if I could help he said "It's something electrical, I just lost all power at the light" I said it might be the main fuse and asked if it had glass fuses. He said he didn't know but that the lights came back on but everything went dead again when he hit the starter. Sounds like a bad ground at the battery to me, I said. He pulled the seat off and sure enough the negative battery connection was very loose. So, I tossed him a six way and he tightened the connections and the bike fired right up. They thanked us for stopping with a round of high fives and we rode off in opposite directions. I hope he learned a lesson today. Always check the little stuff and always carry a tool kit.

Well, if it's the original brake line, you'll definitely need a longer line to move the connection. But you should probably replace the rubber hoses anyway due to age and deterioration. That is if you have an '83 with the same rear MC as I do anyway. My rear MC is significantly different in configuration than the diagram in the service manual depicts. My question to any who have de-linked is why not remove the proportioning valve and tie directly into the MC without the valve?

I'd label that as "dinnerapplebees060918" or wherever/whenever. But why not open it in paint and tag the people?

Those are definitely for "Wing" air deflectors. I'd be interested in them if you decide to sell them.

I read this when first posted and checked my side stand to find the jamb nut loose and a good amount of wiggle. I just got around to fixing it with grade 8 1/2" hardware. Thanks Randy!

I fixed my loose side stand with grade 8 1/2" bolt and nuts.