LaFartessa Posted June 4, 2017 Share Posted June 4, 2017 Just purchased a used '16 FJ. When I took it for a test-ride, I honestly was looking around for a police vehicle- the whine was so loud it seemed like a siren. And this was with my customary earplugs. When I returned, asked the owner about the sound, and he hadn't noticed/didn't know the origin. Looked more closely at bike and found the chain bow-string tight. He'd gone by the owner's manual spec, AND he weighs 265. He loosened it up to my desired spec, and another test-ride resulted in no siren sounds. It's hard for me to imagine how he couldn't have heard that tranny whine. I can only hope that damage hasn't been done to bearing or seals. Link to comment Share on other sites More sharing options...
aeg Posted June 4, 2017 Share Posted June 4, 2017 And rear tire on the ground ...this is just like the oil debate. I measure on center stand, rear wheel off the ground... ~25-30mm. The tire on the ground is from the Yamaha owners manual for the FZ1. I can't imagine that would change for the FJ09. Link to comment Share on other sites More sharing options...
aeg Posted June 4, 2017 Share Posted June 4, 2017 Seems like whoever wrote this manual had too many sake shots. ? I'm sticking with FZ1 manual. Link to comment Share on other sites More sharing options...
Premium Member britelitebob Posted June 4, 2017 Premium Member Share Posted June 4, 2017 Page 7-24 Owners Manual. The slack figure is stupid... but the procedure is there. Well, I probably shouldn't get mixed up in this but since there's so much confusion over this issue ill just point out that the arrows showing where you take the measurement, #1 are also incorrect. That measurement should be taken from the same point on the chain, not the top and bottom as shown. BLB Link to comment Share on other sites More sharing options...
Premium Member DavidS Posted June 4, 2017 Premium Member Share Posted June 4, 2017 How I adjust my chain on my FJ-09: 1) Put FJ-09 on the center stand 2) Place a ruler on the ground at the center point of the chain 3) push the bottom portion of the chain up and measure the slack (how much the chain moves) 4) If it moves <= 1 inch, do nothing 5) If it moves > 1 inch, adjust chain Link to comment Share on other sites More sharing options...
xlxr Posted June 4, 2017 Share Posted June 4, 2017 There should not be any confusion about proper chain slack. The chain is tightest when the rear wheel axle is in line with a line formed by the center of the front pulley and swing arm pivot bolts. As the rear wheel axle moves further away from that line, up or down, the chain slack increases and is loosest at furthest point of travel away from that line. Prove this for yourself by taking off the rear shock mount and watch chain slack change as you move the wheel through full range of travel. Chains are NEVER meant to be adjusted so tight that all the slack is taken out at the point in wheel / swing arm travel where the chain is tightest. If you overtighten the chain, with the shock disconnected, you can feel the overtightened chain bind up wheel / swing arm travel. You can prove this for yourself, put the bike on the center stand, disconnect the rear shock mount, with the wheel hanging down, tighten up the chain as much as you can, then try to move the wheel / swing arm through full travel. The over tightened chain will not allow the wheel / swing arm to move to, or beyond, the line drawn through front pulley and swing arm pivot bolts. If you can feel the chain binding up wheel / swing arm movement, at the very least you will wear out chain and sprockets much faster, at worst, you will damage tranny, wheel, swing arm bearings. Adjusting the chain from too tight to just loose enough can be a fairly sensitive adjustment. Once you get some slack in the chain, a little extra slack beyond that point is not nearly the problem that a little too tight is. When my bike was new, and replacing shock, I took my shock off to check chain tension, 25 mm, bike on the kick stand, with all the slack out of the top run of the chain, is the MINIMUM chain tension needed. Adjusting the chain tension on the center stand will require more than 1 inch (25 mm) chain slack because the wheel will be further in the travel than on the kick stand. It is easier for me to check tension with bike on kick stand. I just checked the difference in chain tension on center stand 70 mm, on kick stand 33 mm. That is a huge difference, so 25 mm on center stand is way too tight. Another point to remember, new chains need one or two adjustments as they stretch and sprockets wear in. I have 7,000 miles on my bike, it has been 4 or 5 thousand miles since I last adjusted my chain, and will not bother to adjust it again until ..... I feel like it. Never listen to any one, dealer or service manual, who says anything differently. Link to comment Share on other sites More sharing options...
xlxr Posted June 4, 2017 Share Posted June 4, 2017 5 mm chain slack at full extension, on the center stand, is WAY too tight. Disconnect your shock and try to move the wheel through full travel, then report back. The proper way to set chain slack is at it's tightest point, not the loosest. " .... so long as you still end up with slack at full extension. " That phrase alone proves you are not understanding that the chain is tightest when the axle is in line with center of front pulley and swing arm pivot points. At full shock extension, chain is loosest, and may be overly tight when everything is in line. If you do not understand that, every thing else is wrong. "... That was with the preload adjuster at my preferred setting (5). I then turned the preload to the softest (1) and then the hardest (7) setting, and the slack remained the same (+/- 2mm), on the side stand." This is also a meaningless exercise because you did not measure the difference in wheel travel in relation to the tightest point. "... I get that the distance between the sprockets increases with suspension compressing" This statement is also incorrect. From full extension of the shock, the chain gets tighter as the axle approaches the tightest spot with axle in line with center of front pulley and swing arm pivot bolts. Once the axle moves above that line, the chain gets looser again as the shock continues to compress. I'm not trying to pick on you, just trying to help guys understand. I am waiting for a few other guys to measure chain slack on kick stand and center stand. Link to comment Share on other sites More sharing options...
xlxr Posted June 4, 2017 Share Posted June 4, 2017 "Oh, I understand... the wheelbase extension my friend." There will be a big difference from full shock extension, and longest wheel base position. But since you clarified that, 5 mm slack at full wheel base extension is still the MINIMUM. I don't know if there are any published specs on too much slack. But that does not concern me because I will never let my chain get that slack. That is not the way I look at it. The wheel base will be longest when the axle is in line with the center of the front pulley and swing arm pivot bolts. It is far easier to put a straight edge along those two points and, with the shock disconnected, move the wheel axle into alignment. I use a automotive car ramp to slide under the tire and raise it till everything is in line. I only do this one time when the bike is new, to verify minimum chain slack. From then on, I adjust it on kicks stand. Link to comment Share on other sites More sharing options...
Premium Member DavidS Posted June 5, 2017 Premium Member Share Posted June 5, 2017 ................. I am waiting for a few other guys to measure chain slack on kick stand and center stand. I measured on the kickstand and got just under 1 inch chain slack I measured on the side stand and got just under 1 inch chain slack Seems like both give me the same results................ Link to comment Share on other sites More sharing options...
xlxr Posted June 5, 2017 Share Posted June 5, 2017 I just figured out how you get the same measurement on kick stand and center stand. Either your spring rate is too high, or your spring rate is too low and you compensated with too much preload. Bike sag refers to how much the rear end drops under bike weight alone. Rider sag refers to how much the rear drops with bike and rider weight. If the shock does not compress under weight of the bike when on the kick stand, you will get the same chain slack measurement as on the center stand because in both cases, the shock remains fully extended. Now that I am thinking about it, I have not checked my bike sag or rider sag in a long time. It is possible I have too much rider sag if the spring has loosened up a bit. I'll have to double check that tomorrow. Link to comment Share on other sites More sharing options...
xlxr Posted June 7, 2017 Share Posted June 7, 2017 Now you are on the right track, but it makes me wonder why my numbers are so different. I will have to double check and see if I did something wrong. Link to comment Share on other sites More sharing options...
kiwicanuck Posted June 7, 2017 Share Posted June 7, 2017 I took mine for a ride today after setting to 30cm on the centre stand I noticed a lot of new odd sounds, the alignment is spot on I think as I even used calipers to measure each side, any ideas. Link to comment Share on other sites More sharing options...
kiwicanuck Posted June 7, 2017 Share Posted June 7, 2017 I will recheck and put back to 25mm just to see if noise goes away. Well spotted piotrek , I just had a good laugh. Link to comment Share on other sites More sharing options...
xlxr Posted June 7, 2017 Share Posted June 7, 2017 The best way to set chain tension is by checking it with shock disconnected and with axle in line with center of front pulley and swing arm pivot bolts. That is the way the chain is supposed to sound. I find it hard to believe that an extra 5 mm can make any difference in sound, unless you already have some bearing going bad. You can double check and make sure chain is not hitting any thing when it is loosest, at full shock extension. Link to comment Share on other sites More sharing options...
ogryder Posted August 17, 2017 Share Posted August 17, 2017 New on the forum, and new owner of a FJ-09. It's a bit sad to find out here that, Yamaha could allow a Typo to cause so much damage. After riding my new bike home and getting good look at her in my garage. Notice chain seemed tight then looking at the owners manual spec me self that can't be right. Earlier today went for a 50 mile ride and notice a loud whine coming from trans when under load in 6th gear, and vibration through the handle bars at 4k-4.6k. (See post about vibrations). Just thinking this has been built into these bikes for over 2 years now. My bike being built this past January. Link to comment Share on other sites More sharing options...
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