rock hard front suspension
- Thread starter Mckeith
- Start date
kiltman
Site Supporter
- Joined
- Apr 27, 2013
- Messages
- 3,282
- Age
- 68
- Location
- Stratford, Ontario Canada
- Bike
- 2002,ST1100ABS
- STOC #
- 8826
Might be due for an overhaul, I just had mine done on a 2002 ABS model. Mine wasn’t leaking but I had new bushings and seals installed and fresh fluid. Made a world of difference.
Curious how long you've owned it and has it always been like that? When I bought my '94 ST, it had like 1 inch of travel before it would hit bottom. I knew something wasn't right, so I drained the forks and put in correct oil amounts. The PO had put WAY too much oil in them and they were hydrolocking. After the oil change they were like butter with full travel.
Slydynbye
Will ride for Pie
2 things to try:
Reduce front tire to 38 PSI
Check fork alignment, Do the loosen and bounce procedure.
It probably won't make a big problem go away but could help a little.
You didn't mention which tire is mounted. Or how old it is.
Reduce front tire to 38 PSI
Check fork alignment, Do the loosen and bounce procedure.
It probably won't make a big problem go away but could help a little.
You didn't mention which tire is mounted. Or how old it is.
ToddC
Site Supporter
Oil level, been there...done that.
T
T
Andrew Shadow
Site Supporter
In addition to the oil level, it may have had oil put in that is a much heavier weight oil than the forks are designed for. I would suggest draining and refilling with the correct oil rather than just adjusting the level if you are not going to do a full flush.
Check the springs as well. They may have been replaced with much stiffer springs.
Check the springs as well. They may have been replaced with much stiffer springs.
rwthomas1
Site Supporter
1. Put bike on centerstand, put a witness mark on the handlebar at the clamp, place towel on top of bike, unbolt handlebar and move it back/lay it down on towel just behind where it mounts.
2. Loosen the top triple tree fork clamps, and then loosen, but do NOT remove, the top fork caps.
3. Remove the fork caps one by one. The bike will sag forward abruptly with removal of the last, so be ready. The forks are now fully compressed.
4. Remove springs. One side will simply pull out, the other will require compression of the spring to remove the top of the damper rod assembly. Its not difficult, but a second set of hands is almost required. If in doubt, review the procedure for changing springs.
5. Remove the little drain plug bolt at the bottom outside of each fork. The fork oil will drain so have some containers ready.
6. Replace fork drain plugs and tighten, you are now ready to add fresh oil.
7. The manual will specify an oil level measured from the top of the fork tube, with the fork fully compressed. I make a simple gauge with a bit of welding rod, straight wire, etc. Bend a 90* and then measure down and nip off the end at the required length. Now you have a gauge. Add oil until it just touches the tip of that wire. Easy.
8. Reassemble in reverse order.
This is a relatively simple service to perform. Some will insist that the forks need to be removed from the bike, new seals installed, etc. etc. If the fork seals are NOT leaking, don't touch them. The fork bushings will be fine until the seals need replacement, so let it be. Change the oil and go ride.
RT
2. Loosen the top triple tree fork clamps, and then loosen, but do NOT remove, the top fork caps.
3. Remove the fork caps one by one. The bike will sag forward abruptly with removal of the last, so be ready. The forks are now fully compressed.
4. Remove springs. One side will simply pull out, the other will require compression of the spring to remove the top of the damper rod assembly. Its not difficult, but a second set of hands is almost required. If in doubt, review the procedure for changing springs.
5. Remove the little drain plug bolt at the bottom outside of each fork. The fork oil will drain so have some containers ready.
6. Replace fork drain plugs and tighten, you are now ready to add fresh oil.
7. The manual will specify an oil level measured from the top of the fork tube, with the fork fully compressed. I make a simple gauge with a bit of welding rod, straight wire, etc. Bend a 90* and then measure down and nip off the end at the required length. Now you have a gauge. Add oil until it just touches the tip of that wire. Easy.
8. Reassemble in reverse order.
This is a relatively simple service to perform. Some will insist that the forks need to be removed from the bike, new seals installed, etc. etc. If the fork seals are NOT leaking, don't touch them. The fork bushings will be fine until the seals need replacement, so let it be. Change the oil and go ride.
RT
It is just a turn of the screw...but there are quite a few screws to turn. You probably should check the sag before you start, to determine if you need stronger springs, or different spacers for preload.
If you do this there's a good chance the bike will lurch forward enough to fall off the center stand, so this technique is very risky. supporting the front end with a jack makes a lot of sense in this application, then you can gently lower the bike once the caps are removed.
Personally, I always take the fork tubes off the bike when doing any work on them. Its not that much extra work to remove them from the bike.
Jack under the engine oil pan, to support the front end. Remove the forks entirely and invert them and pump them to get as much oil out as possible. Just removing the two lower drain bolts won't get all of the old oil out. Use a synthetic fork oil for the refill.
A suspension specialist advised me to use (on my non ABS bike) different weights of oil in each fork, as their internals are different and work more efficiently that way. Left fork gets a 10W-15W weight, right fork gets 7W weight, both filled to the measured level of 7.5 inches from the top of the fork tube, with the spring out and the forks fully compressed.
For an ABS bike, the weight recommendations switch to the opposite forks and the oil level is 7 inches.
Works a treat for me for the last 19 years.
A suspension specialist advised me to use (on my non ABS bike) different weights of oil in each fork, as their internals are different and work more efficiently that way. Left fork gets a 10W-15W weight, right fork gets 7W weight, both filled to the measured level of 7.5 inches from the top of the fork tube, with the spring out and the forks fully compressed.
For an ABS bike, the weight recommendations switch to the opposite forks and the oil level is 7 inches.
Works a treat for me for the last 19 years.
rwthomas1
Site Supporter
Yeah, there's no chance. I thought the same thing. "Oh no! The bike will fall over! I put a strap through the front wheel, and through the centerstand to keep exactly that from happening. Yes, you DO have to catch the bike as the last cap comes off. But its not a big deal, get an extra person to help if you are worried. The bike doesn't "lurch", it smoothly slides down its forks. There isn't all that much weight on the front wheel while on the centerstand either. I'm guessing 50-60lbs, tops. If you are really worried about it, park the bike with the wheel against the wall, or chocked. Or have a helper sit on the back of the seat, holding the front wheel off the ground, then slowly lower it after the caps are off.
Regarding the "not that much extra work". Remove brake calipers, speedo cable, wheel, fender, etc. Then get up under the fairing and break the triple tree clamps loose, etc. That to me is quite a bit, and entirely unnecessary for an simple oil change. I did new springs and an oil change in about an hour and a half.
RT
I typically change the fork oil every other tire change, so I already have the wheel off the bike to begin with, forgot to mention that the last time. That leaves only the fender bolts and triple clamp bolts, hardly any extra work.
I like having the forks removed to pump all the old oil out, makes it easy to do by hand with them on the bench.
edit: even if you don't have the wheel already off for a tire change, removing 4 bolts for the calipers, one screw for the speedo cable, and the axle bolt takes only a couple minutes. Everyone has their own style, but to me those items are easily removed in very little time.
Last edited:
Imho even 38 PSI is too much for the front. Mine rides best with the 36 PSI factory recommended pressures for the front and 42 factory pressures for the rear. If I go much over that I start to feel every bump/ pebble in the road.
I gave up trying to re-fit the right fork leg top washer by myself and now refill the fork, less 10% of the posted volume, with a big syringe bought from a farm shop.
"Jacks?! We don't need no stinkin' jacks!"
Whereas, I had cupping of the front tire (Metzeler) at 36 psi, but cured it with 38 psi. I can't imagine that two psi is going to make the ride "bloody hard", as I believe the OP was insinuating is his problem.
Besides that thought, who has a tire pressure gauge that is that accurate to get it exactly at 36, or 38 psi? Some, like the stick type will read wrong if held with the stick pointing anywhere but straight up.
When I rebuilt my Nighthawk fork, i added 1/4" more fluid than spec'ed for a firmer compression.
I trust the TPMS while I'm riding, so I may as well trust it for filling, too.
My tires slowly seep air, so I top off to 42F/44R, and top off again when either one gets 4psi lower, about a month or so.
I guess you could say my tires see a range of pressures over time.
I trust the TPMS while I'm riding, so I may as well trust it for filling, too.
My tires slowly seep air, so I top off to 42F/44R, and top off again when either one gets 4psi lower, about a month or so.
I guess you could say my tires see a range of pressures over time.