frankd

The readings given in the manual were with the genuine Yamaha electrical tester, which was an analog (actual physical meter to read results). Most analog meters have full battery voltage (1.5 volt DC, on Rx1) across the leads when ohmeter is selected. Most diodes have about a .6 volt drop across them when they are conducting, so if you connect the leads from an analog meter across a diode in the forward direction, the meter will read approximately 2/3 scale. In the reverse direction, it shouldn't move. With a digital meter, as Micarl mentioned, the ohmeter leads only have a very slight voltage across them, and it is way too small to allow the diode to conduct. However, in the special range marked with a diode symbol, the leads do have enough voltage to test a diode. When the diode conducts, the meter will usually indicate .6-.75, and in the reverse direction, it will usually indicate over range ( or 1.----) on a good diode. I gather you are working on a charging problem on your 89. Regulator/rectifiers don't go bad very often. I did have one on my 83 that had 1 diode go bad. The other 5 were still fine. When you tested your stator, did you test the white leads to ground? When you check from any of the white stator leads to ground you should read infinity (open circuit). If your stator is NOT grounded and passes all the other tests in the manual AND all 6 diodes in your regulator test good (BTW, MiCarl was also correct when he said that all 6 diodes likely weren't bad), there is another stator test you can do. Connect a 75W incandescent lamp across each pair of white wires (3 lamps). Then start the bike and bring it up and watch the lights---all 3 should be equally bright. At idle they will merely glow, but at 3K RPM they get pretty bright. The last stator I had to change had an intermittent shorted coil. It read open to ground, and when you first started the bike, all 3 were equally bright. But after about a minute, one went very dim, and another went slightly dimmer. The attached picture shows how bright a good stator will light a lamp. I only used 1 lamp to do the test, but it'd be easier for you to use 3 lamps. Do this test with the stator unplugged from the regulator.

Yesterday when I called my local Yamaha dealer, I was told that the only items that haven't come in were the swing arm bearings. Mine aren't that bad, so I thought I'd just clean up and repack the old bearings and put it back together. That was until I got there and and when I opened the universal joint and rear yoke box I found that the other 2 bearing caps weren't included and had to be ordered separately. The good news is that they are in stock in Wisconsin, and will be at my dealer's Monday afternoon. Grumble, Grumble. It's my fault, I ordered the parts online to pickup at my dealer and it does show different part numbers for the 2 caps and clips. It's hard to understand why they are separate---who would re-use their old caps OR replace just the caps??? The front yoke had to come from Japan! I've attached a picture to show what happened to my u-joint. I don't remember any other discussion about universal joint failures---anybody have one completely bad like mine? BTW, we cut the top part off so we could get it apart easier, but it was also almost as bad as the bottom. I also see that the V-Max and the 2nd Gen. Ventures use the same part. That would indicate that there hasn't been much trouble with it. Another thought--when I backed off the throttle at 75MPH, I felt a vibration. I immediately rolled the throttle back on and brought it down slow so the driveshaft wouldn't be unloaded. I sure hope I'm not in store for a middle gear failure soon.

Here in Illinois, you don't have to wear a helmet when you ride. The only eye protection normally worn by the riders that don't use helmets is a pair of sunglasses. How many tickets has this LEO written for people NOT wearing proper eye protection when they don't wear helmets?

Well, my parts haven't all come in yet. Most came from Wisconsin (I live 50 miles SW of downtown Chicago), but the front yoke is coming from California. Maybe it'll be here Tuesday. I'd be more upset if it was warm and sunny outside, but today and tomorrow are going to be cool and rainy. Frank

Maybe....I think I'd also check it in neutral, turning the back tire over and listen to the u-joint. Although I had no indications or noises until the last 35 miles.

Yes, it was the U-joint. It looks like it was pretty dry and wore down. I found it with one 'arm' worn free. It's amazing that Barb and I got home OK on it last night. Both yokes were damaged. The back one comes with a new u-joint, but I had to buy the front yoke. I'll replace the seal in front of the u-joint while I'm so close. My 83 developed a leak there and I had to pull it all apart to replace the shaft drive seal, so may as well replace it while it's easy. There were a lot of metal chips inside of the swing-arm, and the swing arm bearing was trashed by them. If the parts are available in the Wisconsin parts warehouse, I should have them by Thursday or Friday. If they come from California, it'll be next week. At least we got home....At least we got home!!! Frank

Well, I'm in the middle of exploratory surgery to the shaft drive/rear tire of the 89. Last night my wife and I rode about 50 miles. At about 25 miles, I started to hear a 'clunk' somewhere from the rear every time I started from a stop, and every time I shifted the lower gears. That lasted about 10 miles, and then got quiet. The last 15 miles were on the expressway and I was running about 75 MPH, and when I let off the gas, I felt a vibration. Rolled the throttle back on and it got smooth. From a lower speed it didn't vibrate. I pulled the rear tire off, and the pins on the wheel hub were dry. The rear tire had only been on for about 14K miles, and I greased the pins then. Then I pulled the driveshaft out of the shaft unit--everything was fine, well lubed. Now the only possibility that I think of is the U-joint. Now I'll pull the swingarm and check the U-joint. Anything I'm missing? Frank

Is there any chance that your handle grip is loose? If in doubt, try to pull it off. If it comes, it was loose.

I also had a Black & White YM1 (305). The first time I pulled the heads to de-carbon the heads and piston tops, I found 2 head gaskets installed on each cylinder. I put it back together with 1 and the added compression woke the beast up. This one was very fast. My brother bought it from me when I bought the TX-500. He rode it a while and trashed the transmission. I found him another 305 for sale, and he bought it. This one was timid. My 305 used to foul spark plugs all the time, hated to run below 4,000 RPM, and like to keep the front tire up in the air. The 2nd 305 had no top end power, never fouled a plug--heck, it hardly smoked at all. Night and day difference.

I called my friendly Yammie dealer, and he told me that Yamaha no longer made Quick Gasket, and that the silicone sealers replaced it. Frank D.

I'm in the process of rebuilding the water pump off of my 89, and when I removed the old coolant seal, I could see that it had some kind of blue sealant applied to the outside OD of the seal. I looked it up in the manual, and it said to use "Quick Gasket" around the seal. What is Quick Seal equivalent to? The RTV based sealants used to replace gaskets? Frank D.

I bought my 83 brand new. I never babied it---I ran it though the gears thousands of times, shifting hard. When I was young and foolish, I used to often power shift it. Mine started popping in and out of 2nd gear @ 79,000 miles. I rode it until about 82K and rebuilt the transmission. Now the bike has 140,000 miles on it, and shifts great. This happens to most 83-early 85 bikes, but a few must have been put together a little tighter because some didn't develope this problem. In addition to a harder thrust washer, Yammie redesigned the dogs for 2nd gear. Some happened real early and were fixed under warranty. Some of the fixed units were marked with a punch mark near the the engine serial number. Another problem you need to know about on the 83's (only) is the frame breaking where the center stand and rear shock attach to the frame. Mine happened at 90K. I travel quite a bit 2 up with the bags stuffed, so this may have something to do with it. Some have said that theirs rusted and came apart. This may be true, but mine wasn't rusty. Mine appeared to be caused by metal fatigue. Some have done repairs by welding braces in, but I just replaced the frame with one from an 84. I feel that some of the metal fatigue may have been aggravated by the rear suspension bottoming out (low air pressure). I didn't regularly bottom mine out, but of course it happened some. Make sure you don't run the rear suspension too low on air. BTW, the Yamaha redesigned the frame and made the area that fatigued much heavier on the 84 frame. Some have added braces before the frame breaks which may be a good idea. Frank D.

You don't want to tighten those screws too tight!!! When mine were seeping fuel, I found that the O rings around the screws (you have to pull the screws out to see them) needed to be replaced. Over-tightening the screws won't fix this leak, and will make the screws way harder to loosen next time. Make sure you have a phillips screwdriver that fits good! Metric phillips and SAE phillips are NOT the same. To drain the carbs, all you have to do is loosen these screws.

I don't think anybody answered your other question....yes, you can remove the petcock with the the tank on the bike. I don't remember exactly what I used to remove the screws, but I did have the petcock off of my 83 many years ago, and I don't remember it being all that difficult. I probably would have used a phillips head socket on my 1/4" ratchet. To get the bag locks to release on my 83, I put the key in the middle position, then take a long thin screwdriver or my pocket knive and push the locking mechanism to the retracted position. While it's retracted, I turn the key the rest of the way, which holds the mechanism open. This is way faster than removing the entire lock. I also found that when you flood the lock with WD-40, the mechanism works better (still not like it did when new though).

Well, it looks like there are too many tickets for a hat, so please put my name in the barrel. Frank D.

Also, one of the cables may be adjusted too tight. They need just a little free-play.

The first think I'd check would be the battery. It sounds like it may have a bad connection internally. Connect a battery charger across it and measure the voltage across the terminals. I suspect it'll be pretty high (16volts or above). Also make sure the electrolyte level isn't extremely low.

What's wrong with the 89 engine that you're considering this? It's not a quick job!! Do you have the entire 91, or just the engine/trans? Frank D.

Randy, I just noticed that you have an 83, and a bell went off. Every time I had a very weak battery OR old spark plugs, my 83 would be a bear to start especially if it was cold (40 degrees or colder)....it'd crank but no fire. However, it'd bump start easily. My brother has been riding this bike lately, and he doesn't ride it a lot, so he had a lot of trouble with this. He'd charge up the battery a little bit, and it'd start right up. I did quite a bit of work on it last spring, and I removed the TCI and opened it up to check the diodes....everything inside looked perfect, so I decided to just put it back together and reinstalled the TCI. He'd put a new DEKA battery in the year before, and I also installed new spark plugs. He took the bike back home and about a week later he called me up and told me the bike now started instantly...no more problems. I know the new plugs helped, but it was more than that. Maybe the TCI connectors benefited by being removed and re-installed. I do know that my 89 is way different. I knew that the day I brought it home. It was in the upper 20's outside, and I trailered it home. We unloaded it, turned the key on, and it started instantly. No way would the 83 start that willingly at that temperature. Even with high mileage plugs, and an almost dead battery, it fires right up. Besides the way the boost sensor is connected, there is a another difference in the TCI, because the only Ventures that have the weak spark problem at lower voltage are the 83s. I checked the spark strength on the 83 with it running before I pulled the TCI and it was strong. But that was at higher battery voltage. Put brand new plugs in and gap them a little tight and your bike will start better. Maybe you could excercise the TCI connectors also. Take an ohm meter and measure from the plug connectors to ground and make sure you don't have an open plug wire (they should measure less than 20Kohm to ground). I can't say that will help for sure, but my brother says it's night and day difference now. Or you could install a later TCI and change the way your boost sensor is plumbed, OR buy and install the new style ignition module from Dingy. Then your problems will be solved.

Also, sync. the carbs. A lot more noises are heard when you have 1 weak cylinder.

Test the stator and make sure it is NOT grounded. You only need to check 1 lead to ground....if the stator is grounded all 3 leads will measure to ground. If it's not grounded the best way that I've found to test the stator is to connect three 115V, 75W incandescent lights across the 3 pairs (A to B, A to C, and B to C). All 3 should light equally when you bring the engine up to about 4,000 RPM. The last bad one that I replaced had intermittent shorted turns. It was NOT grounded, which surprised me. When I connected 3 light bubs across the 3 stator pairs (not connected to the R/R), when I first started it up, all 3 would light equally. Then after a minute or so, 2 of the light bulbs started going dim, and the 3rd was still reasonably bright. To connect the light bulbs, I used the sockets with pigtail leads. These are the kind that the used car lots used to use in the early 60's. They also use them on some construction sites and they should be available at Home Depot or Lowe's. Frank D.

Yes, the normal vacuum @ 1000 RPM is little over 9" of mercury. Frank D.

Last week I mentioned that I'd read a test of penetrating oils online and it agreed that the ATF/Acetone mix was the best. I don't have the website, but here is a printed version.

I saw a test on loosening rusted bolts online that indicated the torque needed to break them loose, and it also said this was the best by a longshot. It also said that you could mix ATF 50/50 with lacquer thinner and get the same results if you didn't want to use acetone. The next best penetrant was Kroil, then Liquid wrench. PB Blaster was only slightly better than WD-40. However, I do wonder if for some applications things come out different. I was getting my old Dodge Ramcharger painted, and wanted to pull off the trim. Some of the tailgate trim bolts wouldn't budge, so I soaked them with Kroil for a couple of days, but they still wouldn't loosen. A guy at work suggested PB Blaster, so I picked up a can and sprayed it. I let it sit overnight, and the next morning it loosened up easily. One of the mysteries of life, or did the Kroil finally do it's job? Did the solvent in PB Blaster let the Kroil sink into the threads?

I'd also be interested in a set....