cordodor
Full Member
'79 SR500
Posts: 109
|
Post by cordodor on Jul 14, 2007 19:45:21 GMT -5
I've got the front end of my bike torn apart and I'm trying to replace the fork seals in my '79 ( i think all years used the same forks ) I've got the forks out of the yolks and am attempting to remove the hex key bolt from the bottom of the fork as that is step one in the manual I got today as to how to tear these things apart. I broke it loose, but I turn it and turn it and turn it and it never comes out. I am making sure to hold the upper tube steady and just turn the bolt and still nothing. This same thing is happening on both forks. I'm kind of stuck as to what to do. Any ideas?  Also, does any one happen to know what size hex key to use on the tops of the tubes? IT'S HUGE!!!!! and I dont have that tool yet.   |
|
|
|
Post by G Man on Jul 14, 2007 22:05:39 GMT -5
I've got the front end of my bike torn apart and I'm trying to replace the fork seals in my '79 ( i think all years used the same forks ) I've got the forks out of the yolks and am attempting to remove the hex key bolt from the bottom of the fork as that is step one in the manual I got today as to how to tear these things apart. I broke it loose, but I turn it and turn it and turn it and it never comes out. I am making sure to hold the upper tube steady and just turn the bolt and still nothing. This same thing is happening on both forks. I'm kind of stuck as to what to do. Any ideas? It sounds like you have not pulled the top caps and fork springs out yet. I might do this first before proceeding to remove the damper rod bolt. After you have the springs out, and providing you do not have air tools, you need to make a long tool to hold the damper rod inside the fork tube to stop it from turning while you remove the damper rod bolt from the bottom. The better way of course is to use an impact and rattle the bolt out. No need to hold the damper rod this way. If you do not have your own air tools, maybe there is someone you can go to and get them to zip 'em out. I believe the hex socket size to be 17mm. In a pinch, you could go to your hardware store and pick up a short 10mm bolt. Install two jam nuts on the bolt, flip it upside down and use the head of the bolt to fit the cap. Use a wrench to turn the bolt by the jam nuts you have installed. Someone can correct me on the sizes above if necessary as I don't get to work on the bench too much, d**n service mgr... G Man |
|
cordodor
Full Member
'79 SR500
Posts: 109
|
Post by cordodor on Jul 14, 2007 23:06:02 GMT -5
Thanks for the info G Man. You assume correct. I have no pneumatic tools. I'm not exactly sure how i'm going to rig such a tool to hold the damper rod inside, but I'll try to get creative. Also, when you tighten it back up do you have to do the same thing? Hold it from the inside while you turn the bolt on the bottom of the fork?
Nice tip on the 10mm bolt. If i can't find a 17mm hex, i'll try that trick.
|
|
|
|
Post by canucksr on Jul 15, 2007 0:14:44 GMT -5
If you clamp the fork in a vice...be sure to use soft-jaws and be prepared for the spring to fly out when you loosen the 17mm cap.
|
|
|
|
Post by sjef on Jul 15, 2007 5:45:43 GMT -5
hallo cordodor, rebuild the fork in the yoke fix the clamps and then release the forkcaps, it is much easier this way.if heard of guys using a wooden broomstick to hold the damperrod  regards sjef |
|
cordodor
Full Member
'79 SR500
Posts: 109
|
Post by cordodor on Jul 15, 2007 9:43:11 GMT -5
yeah, i dont have a bench vice either, so leaving them in the fork yolks seems to make pretty good sense. Perhaps I'll put one back in before i start work again today. I'll make sure to wear my gloves and safety glasses when I pull out that plug. I just hope I dont lose the spring! It's good to be prepared for it though.
I wish Yamaha would have put that big bolt on top like they did with the XT and TT. Much easer to remove.
|
|
cordodor
Full Member
'79 SR500
Posts: 109
|
Post by cordodor on Jul 15, 2007 9:45:38 GMT -5
Am I going to have to take the WHOLE fork apart in order to replace the fork seal?
|
|
|
|
Post by canucksr on Jul 15, 2007 10:34:58 GMT -5
Once you remove the Allen bolt from the bottom, and remove the fork-tube from the slider....the seal can be replaced.
|
|
cordodor
Full Member
'79 SR500
Posts: 109
|
Post by cordodor on Jul 15, 2007 14:42:12 GMT -5
It sounds like you have not pulled the top caps and fork springs out yet. I might do this first before proceeding to remove the damper rod bolt. After you have the springs out, and providing you do not have air tools, you need to make a long tool to hold the damper rod inside the fork tube to stop it from turning while you remove the damper rod bolt from the bottom. The better way of course is to use an impact and rattle the bolt out. No need to hold the damper rod this way. If you do not have your own air tools, maybe there is someone you can go to and get them to zip 'em out. I went to the store today and bought a 17mm hex end for my 1/2" ratchet. Apparently the same style bolt is used for drain plugs in VW, BMW, and Porsche autos. I pulled the cap bolt off the top like you said, but I'm at a loss as to how to get the spring out of the top. nothing popped out at me, that's for sure. It seems like there is a nylon or plastic spacer in the tube first, but it doesn't look near as long as the one in the drawing in the manual. after that, there looks to be some empty spaceand then something else at the bottom of that empty space with a hole in it that I can only assume is the Spring Seat. How do i remove the spring through all this? I'm a computer guy and this is probably the biggest mechanical project I've attempted on my own. haha. Thanks again for the help |
|
|
|
Post by G Man on Jul 15, 2007 16:58:11 GMT -5
It sounds like you have not pulled the top caps and fork springs out yet. I might do this first before proceeding to remove the damper rod bolt. After you have the springs out, and providing you do not have air tools, you need to make a long tool to hold the damper rod inside the fork tube to stop it from turning while you remove the damper rod bolt from the bottom. The better way of course is to use an impact and rattle the bolt out. No need to hold the damper rod this way. If you do not have your own air tools, maybe there is someone you can go to and get them to zip 'em out. I went to the store today and bought a 17mm hex end for my 1/2" ratchet. Apparently the same style bolt is used for drain plugs in VW, BMW, and Porsche autos. I pulled the cap bolt off the top like you said, but I'm at a loss as to how to get the spring out of the top. nothing popped out at me, that's for sure. It seems like there is a nylon or plastic spacer in the tube first, but it doesn't look near as long as the one in the drawing in the manual. after that, there looks to be some empty spaceand then something else at the bottom of that empty space with a hole in it that I can only assume is the Spring Seat. How do i remove the spring through all this? I'm a computer guy and this is probably the biggest mechanical project I've attempted on my own. haha. Thanks again for the help I don't know what's going on with your set up, but the spring should be under some load and generally will extend out some when you remove the retaining cap. Take caution that one of the pieces is not jammed and could un-load some. Look through the attached image and see if you can sort out what is going on. G Man  |
|
cordodor
Full Member
'79 SR500
Posts: 109
|
Post by cordodor on Jul 15, 2007 18:19:24 GMT -5
i have that same diagram in the manual i bought. #16 looks like it's been tampered with maybe or is missing. what i have in its place is what looks to be a pvc pipe that's been jammed in there and I cannot remove it. Either these things have been quite modified, or they are from a different model bike.
I had a friend come over who has recently rebuilt the forks on this bike and he said that his look just like the diagram and there's something different about mine. I'm gonna take them to Yamaha and see what they have to say. I really would rather not replace them...
|
|
|
|
Post by StewRoss on Jul 16, 2007 2:43:53 GMT -5
There should be some preload on the caps as you remove them from the top of the fork. Because of that you need to be carefull as you fully undo them...push down on them for the last few threads as you undo them...they should pop up into your hands. If there is nothing there to do this then either the spacers have been left out of the springs have been played around with. There should not be a tight fitting spacer in there...have you ridden the bike? How did it feel? I'm interested to see what this is... SR |
|
|
|
Post by canucksr on Jul 16, 2007 8:36:32 GMT -5
If I pull the top caps off my forks...there's the cap, a spacer, a spring seat, and then the spring. It pops out a couple of inches when the cap is removed. Cordodor...It sounds like something's missing in your assembly.
|
|
cordodor
Full Member
'79 SR500
Posts: 109
|
Post by cordodor on Jul 16, 2007 9:30:00 GMT -5
There should not be a tight fitting spacer in there...have you ridden the bike? How did it feel? I'm interested to see what this is... SR I too am interested to see what it is. The spacer that is in there is very tight and I can't get it out pulling on it with my finger. Also, the spring cap #15 was not butted up against the "spacer" like I thought it should be. It seemed to be way down in the tube, held in place by something else... I was expecting that spring and spacer to pop out at me, but nope. I'm taking it in to Yamaha tomorrow to see what they have to say about it. I'm also going to e-mail the guy I got it from to see if he knows anything about them. He should be back from his trip today, so hopefully he'll answer his e-mail. I rode it VERY briefly just up and down the street in front of my house. It felt okay, but since I had crappy tires, no air filter, no registration, and a noisy engine, I didn't go very far. On a happier note, my tires should arrive tomorrow |
|
|
|
Post by miker on Jul 16, 2007 11:49:10 GMT -5
A short PVC spacer is a sign that the bike may have Progressive springs - they rec that you replace the spacer with a 1/2" something, Thuperstuff says to use PVC.
But yeah, your spring should come out the top. Be really careful ok? It could be ready to fly out.
Actually the standard tool kit has a tool to take the big hex plug out of the top - you stick the spark plug socket thru the double box wrench, and the little end of the spark plug wrench fits the hex in the top of the fork tube.
Make a tool to remove your damper by getting a 2-foot threaded rod and a couple 17mm nuts back to back on each end of it. That will hold the damper inside and give you something to get a wrench on.
Once you have the lower leg seperate, heat the end around the seal with a hairdryer or air gun to the point where its pretty warm to hold. The seal comes out (and the new one goes in) much easier with heat. Use the old seal on top to help you tap in the new one square.
miker
|
|
