Bagstr 288 Posted August 12, 2013 As August is part of my Slow riding season, bike maintenance is my only moto recreation. At 12 months and 148 hours a suspension service is in order. Hear is the point of this post. A question. The manual specs 110mm air gap on the forks. Well, how and where is this measured? My method was as follows: screw out all adjusters, compress spring, insert wrench and remove preload/cap, remove spring, compress fork. At this point the oil was 125mm below top of outer tube. Mmmm. I flushed new fluid about three times while exercising the dampening rod, then installed 620ml of 5wt Maxima. Again, I measured top of tube to fluid, 80mm ?? Mmmm. Install spring and spring preload cap. Cleaned dust seal and lower tube. I was expecting the fluid to be the manual spec 110mm, but no 80mm without sping. There is no way I can see to measure the air gap any other way that I can think of. Anyone have an explanation?? I am thinking the cartridge had not sucked up all it's oil. Special Thanks to all offering explanation. Wheel is still off, 2nd tube tomorrow. B Share this post Link to post Share on other sites
amgems 79 Posted August 12, 2013 Dave I've done it this way and it's working good for me. I use the Motion Pro tool for setting level. Jim Share this post Link to post Share on other sites
Bagstr 288 Posted August 12, 2013 Thank You, I will do the second side per { Slavens? ) and see how the measurements match. The Shop Manual notes the precaution on running the spring pre-load all the way down. I admit to not understanding what is being said. Using a wrench, the bottom of the adjuster appears to down without the need to hold the damper rod. I will see if my clicker has full range. Good Stuff Share this post Link to post Share on other sites
tlking6 0 Posted August 12, 2013 Lets discuss this in detail up at Coon labor day weekend while we feast on all you can eat tacos and sip cold brews. You've been officially called out! Share this post Link to post Share on other sites
Spaugh 1 Posted August 12, 2013 you need to measure it with the cap off the rod and no spring with the fork leg compressed. To get air out before final oil height setting, you want to pour in oil, hold your hand over the top of the tube and cycle the fork to get air out of the oil. Once the air is out, use a bic pen or anything you want as a dipstick and make sure you get a oil line at your 110mm line from the top of tube to oil. PS, put new bushings in while you are at it. Share this post Link to post Share on other sites
Bagstr 288 Posted August 12, 2013 "You've been officially called out! " Yeah, that always works to get me moving. He, he. I know much sympathy will come my way when I say, "It's been a long hard summer." Starting to regain some of my Zip, and think of these "Short Hard Weekends" We will see. Share this post Link to post Share on other sites
Suspenders 43 Posted August 12, 2013 To draw the fluid out you can go to the drug store and get an extra large syringe. I saw one guy use a turkey baster. With the syringe you can just put a pen mark at 110mm and put the line at the top of the forks and suck. There is in many manuals a minimum amount of fluid and a maximum amount of fluid. If you were not bottoming your bike at all you might consider putting your fluid level at 120mm initially. This will reduce your bottoming resistance at the last inch or two of travel but will give you a more plush ride. Keep in mind you should bottom the forks once in a great while so you know you are using it all. The reason to go light initially is because you can add fluid through your bleed hole at the top of the fork quite easily compared to taking fluid out. Putting too much fluid will make your forks harsh so do not over do it. The fluid level adjustment is one of the top ten items done when testing to set the bike up properly for an individual. Each time I do a service this is adjusted after talking to my customer about riding level etc. Share this post Link to post Share on other sites
tlking6 0 Posted August 12, 2013 Yeah, that always works to get me moving. He, he. Did I mention all you can eat tacos, Huevos Rancheros breakfast??? And thats just for starters! Share this post Link to post Share on other sites
Bagstr 288 Posted August 13, 2013 Dust Seal appears to be in fine shape. The out of sight oil seal is not leaking and clean. I cleaned the dust seal with the Motion Pro thin plastic hook. Applied White lithium grease to inside of dust seal and pushed into place with hand pressure. Smoke came out with the one year old factory oil. 148hrs. Air Gap - The Shop Manual spec is 110mm. The factory oil was measured to be 125/130mm. I did have occasional hard bottoming. Spring out, damper and outer tube fully compressed. The Shop Manual calls for dumping 620ml into the empty tube. That resulted in a much too high oil level 80mm oil, and too small air gap, Used Motion Pro syringe to set oil to 110mm. Pulled shock and off to see Suspension 101 Tuesday for oil change and check-out. No leaks to this point. Rear rider sag set to 110mm. Note: I am still un-easy about the damper rod assembly spinning while tightening the spring pre-load adjuster. Is the rod threaded at the bottom? Should the rod be held to stop rotation? I did not control damp rod rotation other than holding it with the wrench above the spring to torque the pre-load to 25Nm. Also, that black smoke. My guess is it is a result of friction from the non-metalic spring centering device at the top of the damper rod. Share this post Link to post Share on other sites
Spaugh 1 Posted August 13, 2013 on the end of the rod there is a nut that is threaded on below the cap. you need to spin that nut down away from the rod end before putting on the cap. Then you thread on the cap until it bottoms out on the end of the rod at which point the rod will rotate with the cap and the nut will thread back up until it hits the cap and keeps it all tight. makes sense? smoke is just oil vapor. Share this post Link to post Share on other sites
Bagstr 288 Posted August 14, 2013 After setting the oil level/air gap, use careful assembly to maintain function of the rebound damper adjusting knob. Component Description, Top to Bottom: Rebound damping adjustment tube, Piston rod, Water excluder ???/ Cartridge. The black non-metallic part looks to be a spring centering device for my money. Finally, the outer tube. During assembly without understanding how the components inter-act, a non-performing rebound dampening adjuster developed. It would not find bottom when turned clockwise. After investigation, I determined that during dis-assembly and assembly the cartridge/water excluder was spinning up and down the piston rod. When the black thingy is too far up the threads, the rebound damper adjuster knob would spin off the threaded piston rod. These two photos show the "water excluder" high and low on the rebound piston rod. As I learned, proper installation technique is to spin the cartridge all the way down hand tight. This will expose the maximum length of threads on rod. Install the spring and the loose nylon spacer. Pull spring down while installing an open end wrench. Spin on the pre-load adjuster. There will be a gap at this time between the water excluder and pre-load adjuster. The piston rod is attached in the bottom of the tube and does not spin. By hand run the cartridge up to contact the pre-load adjuster. Torque the pre-load adjuster to the piston rod at 25Nm. Raise the outer tube and spin on the rebound adjuster. I installed the fork tube in the triple and tightened the lower to near 15Nm. With the top triple loose, torque the spring preload adjuster to 50lb. Torque upper triple at 20Nm. At this point run the compression and rebound adjusters clockwise in, and then out to final setting. Turn the spring pre-load adjuster in from full out to final setting. Share this post Link to post Share on other sites