Not that I can tell...looked all original, like it hadn't been taken apart before to my untrained eye.
'91 ST Fork Seals
- Thread starter jmpacella17
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STRider
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I used the fork seal replacement as an opportunity to strip and repaint the legs as mine had enough chips to justify it.
I used VHT Roll Bar and Chassis paint based on recommendations from a YouTuber that was doing a similar service on a different bike. I'm pleased with how it's holding up.
I used VHT Roll Bar and Chassis paint based on recommendations from a YouTuber that was doing a similar service on a different bike. I'm pleased with how it's holding up.
OK, new question/issue on this R&R:
I just replaced the fork seals (91 ST1100, non ABS), and I had a concern. It appears that they are not rebounding the same after compression (they're still off the bike).
I changed the seals, upgraded the springs with Progressive Suspension's and re-assembled. I used synth. 7.5W in the right, 10W in the left, based on the rec. of another ST'er. They both feel about the same in terms of force to compress. However, the left one rebounds almost right away, and the right one takes a beat to return to full ht./length. Do you know if they should be different? Do you know if there is a test/spec. to evaluate the rebound performance?
I unfortunately don't have a baseline to compare them to, and it seemed weird to me that they are different. I didn't want to just put them back on the bike if it was going to pose a dangerous situation. Any and all insights would be appreciated!
I just replaced the fork seals (91 ST1100, non ABS), and I had a concern. It appears that they are not rebounding the same after compression (they're still off the bike).
I changed the seals, upgraded the springs with Progressive Suspension's and re-assembled. I used synth. 7.5W in the right, 10W in the left, based on the rec. of another ST'er. They both feel about the same in terms of force to compress. However, the left one rebounds almost right away, and the right one takes a beat to return to full ht./length. Do you know if they should be different? Do you know if there is a test/spec. to evaluate the rebound performance?
I unfortunately don't have a baseline to compare them to, and it seemed weird to me that they are different. I didn't want to just put them back on the bike if it was going to pose a dangerous situation. Any and all insights would be appreciated!
STRider
Site Supporter
Though I can't say whether your experience is abnormal, I wouldn't expect this to pose a dangerous condition at all. Over the past 30+ years asymmetric damping in telescopic forks has become fairly commonplace - compression controlled by one leg, rebound in the other... Even this 1100 of yours preferentially increases compression damping on the left fork under braking. You did fill each leg with different weight oil after all.
I say reassemble it and take it for a ride. JMHO
I say reassemble it and take it for a ride. JMHO
Thanks for your comments! That seems to be the common feedback I've received from some other off the forum...I'll give it a whirl!
I completed the fork seal replacement, with the help of those who have gone before me. Major props to John O. for his tool kit and helpful advice along the way!
Some notes from my work:
- I took the Honda manual, a parts list that a fellow ST'er put together (sorry, I couldn't find that post again...maybe someone can provide that link) and bought the parts at my local cycle shop
- I upgraded the springs with Progressive Suspension ones (~$120 I think)
- I used synthetic fork oil (7.5W in the right, 10W in the left, per the advice of another ST'er)
- This post was super helpful along the way: http://www.st-riders.net/index.php?topic=907.0
- These videos were super helpful as well:
,
- I found that if I added the amount of fluid (volume-wise) per the manual it didn't match the recommended level when measuring down from the top of the fork tube. Not sure if anyone else encountered this as well? I went by the depth measurement (a little more than the rec. volume).
- As you may have read on this thread already, I seem to be the only schmuck that had a broken mystery seal of some sort in the bottom of the left fork case. Still a mystery as to what it is. Some argue if it's an original part; some wonder if it was even necessary...I still have no clue. Hopefully some one along the way will one day help solve this! I ended up making a mold out of polystyrene and shooting some RTV into it and made my own replacement part in the end since I couldn't find the right sized seal online.
- Holy cow, does this bike ride great now...it feels so much lighter and more responsive. Glad I did this job, and you will be too!
Many thanks again to those who did the job and posted about it; super helpful!
Some notes from my work:
- I took the Honda manual, a parts list that a fellow ST'er put together (sorry, I couldn't find that post again...maybe someone can provide that link) and bought the parts at my local cycle shop
- I upgraded the springs with Progressive Suspension ones (~$120 I think)
- I used synthetic fork oil (7.5W in the right, 10W in the left, per the advice of another ST'er)
- This post was super helpful along the way: http://www.st-riders.net/index.php?topic=907.0
- These videos were super helpful as well:
- As you may have read on this thread already, I seem to be the only schmuck that had a broken mystery seal of some sort in the bottom of the left fork case. Still a mystery as to what it is. Some argue if it's an original part; some wonder if it was even necessary...I still have no clue. Hopefully some one along the way will one day help solve this! I ended up making a mold out of polystyrene and shooting some RTV into it and made my own replacement part in the end since I couldn't find the right sized seal online.
- Holy cow, does this bike ride great now...it feels so much lighter and more responsive. Glad I did this job, and you will be too!
Many thanks again to those who did the job and posted about it; super helpful!
John OoSTerhuis
Life Is Good!
Congrats, Jon. Glad you found the kit helpful.
Hadn’t seen the first video (TheMotorcycleMD channel on YT) you posted. Not sure I’d use the file he used, nor would I ever use the volume method (fluid level only, spec per the manual). And I didn’t see the top/slider bushing installed… which can be an issue on our ST1100s, hence the little brass driver I made for the kit. Quick and dirty though and got the job done, but I’d be loathe to refill by pouring fluid through the bolt hole on the bottom of the silder with the whole fork assembly upside down.
edit: oh yeah… and unlike the first video, our STs have a torque value spec’d for the bottom fork bolt. I do my own work but if I knew my shop would do a fork seals and bushings R&R like that guy I’d find another shop. FWIW
John
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Erdoc48
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Interesting thread: My left fork seal on the 94 started leaking in the past couple of weeks. I bought the Honda OEM parts from Partzilla, as well as a proper driver from Summit Racing and a bike jack. Brings us to today…I removed the forks, no issue, however, to crack loose the Allen bolt in the lower fork, despite using the proper tool, damn thing won’t budge! I’m wondering if the prior owner used Loctite (and potentially worse, red Loctite) on that bolt- I even tried a impact driver to break the bolt free. No dice. I took it to the shop this AM and the mechanic tried to break it loose as well (bolt head is a little stripped)- he said he’s going to use a Torx elongated bit to see if he can break it free, but he won’t have that tool until Wednesday of next week. So my 94 sits on it’s jack in the garage, waiting…
I hope the mechanic can get it to break free, otherwise, I might be looking at a replacement fork (I really hope not). The prior owner used Sonic springs when he installed them and new oil in 2013.
I hope the mechanic can get it to break free, otherwise, I might be looking at a replacement fork (I really hope not). The prior owner used Sonic springs when he installed them and new oil in 2013.
Consider trying an old-fashioned impact driver; the kind you hit with a hammer.
Erdoc48
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I think they tried that. Wouldn’t budge. I really hope the prior owner didn’t use red loctite
Last resort is to use a drill to remove just the head of the bolt.
Erdoc48
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I guess I’ll know Wednesday how it turns out.
I just finished replacing the tires on my 2006. Front wheel removal did not go smoothly at all. The front caliper bolts were stuck tight and I actually broke an old short extension. Given there was no corrosion on the bike, I suspected a misuse of a thread locker at that point. Someone used an excess of red Loctite on all the caliper and bracket bolts. A local independent shop helped immensely. The rear wheel was no problem. I had already removed it to lube the rear end just after I got the bike.
Erdoc48
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It kills me when people use red Loctite inappropriately. Some things were meant to come apart in the future. If the shop can’t break that bolt free, I’ll probably drill off the bolt head, then remove the threads and use a new bolt (which it needs anyway). This was a relatively easy job gone very wrong.
It is quite possible that even if you can break it loose, if the bolt has thread locker on it, the damper rod could simply spin, making it difficult to remove after cracking it loose. If the bolt head is already butchered, I would consider drilling the head off and getting another bolt, before loosening it. If you have to drill the head off because of thread locker making the bolt hard to remove from the damper rod, you may wish you had left it tight to drill, although, with a rattle gun, you may be able to re-tighten the bolt
Erdoc48
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Epilogue…success! The shop was able to break the bolt clean (used an elongated torx bit tapped into the Allen head bolt from Snap On tools when the Snap On rep visited the shop and it was then removable)- unfortunately, the replacement bolt used was not OEM (but same thread pitch and size) so about 1 mm of bolt head was seen when looking into the opening for the axle- I called the shop about that and I think their plan was to grind the head down just a bit to allow for the axle (I can’t leave the house today as a contractor is doing some work on the house). I was going to get the OEM bolt from Partzilla but I really wanted to get the bike back together so I used a Dremel and shaved the bolt head just a bit to allow the axle to fit. I may get the OEM bolt at some point in the future if I need to remove the forks again but I’m hoping that will be some time down the road.