ST1100 Hyperpro Fork Springs

If you haven't done anything about your rear spring the combi kit from hyperpro upgrades the rear spring... (from the hyperpro link above).

I am very pleased with my front and rear hyperpro springs and shock/spring set up on my '01.
 
ST1100Y said:
According to their site (http://www.hyperpro.com/hyperpro/en/node/21) yes
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I wonder if any of you know what parts I need to refurbish the forks on my 01 ST1100 abs? there is a chatter in the forks,most noticeable say below 50 mph, on my VFR it's much worse,so I think the VFR's forks need the same attention,but I am going to do the Pan first.
I think I need new bushions,I wonder if the seals will be ok to refit since they are not leaking? or should I get new seals?
I am going to get the hyperpro fork springs and motul 10wt oil.the oem spacers will work with these.
I fitted the new wilbers 640 shock today,amazing difference,although I have to allow I am coming from a totally kaput oem shock.
 
broc11 said:
I wonder if any of you know what parts I need to refurbish the forks on my 01 ST1100 abs? there is a chatter in the forks,most noticeable say below 50 mph, on my VFR it's much worse,so I think the VFR's forks need the same attention,but I am going to do the Pan first.
I think I need new bushions,I wonder if the seals will be ok to refit since they are not leaking? or should I get new seals?
I am going to get the hyperpro fork springs and motul 10wt oil.the oem spacers will work with these.
I fitted the new wilbers 640 shock today,amazing difference,although I have to allow I am coming from a totally kaput oem shock.
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Not sure what exactly you mean by 'chatter', but make sure its not the steering stem bearings first. Put bike on centerstand and raise front wheel off the ground, remove wheel. Grab both upper fork tubes and try to rock them in the direction the wheel travels. If you get play by doing that then the steering stem bearings are loose. Now do it again holding onto the lower fork tubes, if you get play doing that then your bushings likely need replacement. You can also try it with the wheel still on the bike, but you probably get a better feel for things without the mass of the wheel and tire in the equation.

New seals are very cheap, so you should replace them while you're in there, it would be false economy to reuse the old ones especially if you don't know how old they are. Aftermarket seals are as good as OEM, and cost about $15 a pair or so.
 
broc11 said:
I think I need new bushions,I wonder if the seals will be ok to refit since they are not leaking? or should I get new seals?
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Well, since you'll need to disassemble the forks in order to get the new bushings in (besides other works like flushing everything intensely) you will need new fork seals... and the proper tool to put them in. While having the forks in parts I'd also suggest the following: install the new bushings, oil them slightly and assemble only fork tube with bushings; then move the fork tube in small increments/steps in from 'fully retracted' to fully compressed and try to wiggle it on all stops to figure out any wear on the fork bottoms. We'd some bad cases (oil change and shot bushings neglected for many miles...) where the bore of the fork bottoms had worn-out to an oval (barrel) shape, hence even with new bushings installed quite some gap, thus loose front wheel guidance was given. Some 'camouflage' this by deciding '..this Japanese suspension engineering sucks! I need a fork brace...' which is however not fixing the true issue though...

I fitted the new wilbers 640 shock today,amazing difference,although I have to allow I am coming from a totally kaput oem shock.
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Suspension upgrade is not complete until front and rear have matching spring character and damping. No use in having like a soft front which 'collapses' in a compression, while the rear stays firm... the impact on steering geometrics alone... So it might take you some time to figure out the proper setup on which fork oil works best with which shock settings (throughout the various payload conditions given ;-) ), but once that's figured out, you'll end up with an amazing ST1100, awarding with precise cornering abilities, previously unknown stability/tracking in high speed turns (even in full regalia with two up and luggage for two weeks) and noticeable improved stopping performance.
Riding my '00 model with suspension upgrade and the '94 ST with its worn down OEM kit, is like day and night... I seriously need to upgrade the '94 as well, in comparison it feels like riding my living room couch... :D
 
Thanks for the replies guys, changing the shock was so easy,though expensive, doing the forks will be the difficult but a lot cheaper,I think I will replace all the parts you have suggested,the head bearings seem fine but I will install the 'all balls' tapered bearings when I am at it,
I done that on the vfr already, the oem roller bearings were completely gone on her,big notch in the steering when I turned the front wheel from side to side.
What I mean by 'chatter' is hard do describe,it's like as if something is out of place inside the forks,same thing on the vfr only worse,at higher speeds it's not noticeable.
I thought when I replaced the stem bearings on the vfr that it would go away but it's still there, so I suspect it's the slider bushings.
 
broc11 said:
What I mean by 'chatter' is hard do describe,it's like as if something is out of place inside the forks,same thing on the vfr only worse,at higher speeds it's not noticeable.
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Possible that its the linkage of the LHS front caliper to the anti-dive mechanism? If that hasn't been lubed regularly the bores might be a bit worn out, so when running over small obstacles you'll feel/hear the caliper 'rattling' around. Some waterproof marine grease (or at least some Moly paste) should deal with that.
 
ST1100Y said:
Possible that its the linkage of the LHS front caliper to the anti-dive mechanism? If that hasn't been lubed regularly the bores might be a bit worn out, so when running over small obstacles you'll feel/hear the caliper 'rattling' around. Some waterproof marine grease (or at least some Moly paste) should deal with that.
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Thanks, I will look into that,that sounds like it could be the issue,hard to believe I suppose that its coming from inside the forks.
 
broc11 said:
Just looking at this pic from ebay, they look like ordinary progressive springs from this pic don't they
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Yep, regular '2 step' springs...
From their catalogue I can ID 3 spring types: SP-HO11-SSA002, ST1100 '90~'01 (apparently non-ABS/standard), SP-HO11-SSA003, ST1100 '92~'95 (obviously ABS-I) and SP-HO11-SSA004, ST1100 '96~'01 (thus ABS-II/CBS) (see details in catalogue http://www.hyperpro.com/hyperpro/sites/default/files/Hyperpro%20Springs.pdf page 7). Maybe you'll have to specify [linear] during the ordering process (I did so IIRC...)
 
ST1100Y said:
Maybe you'll have to specify [linear] during the ordering process (I did so IIRC...)
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That's what I was thinking Martin, what you have fitted is the hyperpro linear spring,
that spring on ebay is a progressive type spring,same as the oem.

Thanks for that hyperpro catalogue, where can I order those springs from? 125 euro isn't bad.
 
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ST1100Y said:
Maybe you'll have to specify [linear] during the ordering process (I did so IIRC...)
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I don't see how I can specify 'linear' when ordering as there is only one choice of spring for the abs2? SP-HO11-SSA004

looking at performance parts website, this is the only option;
http://www.performanceparts-ltd.com...eringDampers/174707-Hyperpro__Fork_Spring_Kit

from that pic it looks just like any other progressive spring to me,they say in their literature,'it's the perfect setup' with a slightly different spacing between every spring coil, linear/progressive as they claim,maybe they look different in the flesh,but from that pic it looks like a tightly wound spring at one end, and a softer spring,with similar looking spacings most of the way down.
I wonder what rate the spring is? someone said here the oem spring is rated at .6

one final question Martin, do you use the saito aftermarket oil seals,dust seals and tapered headstock bearings from Louis? thanks
 
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broc11 said:
I don't see how I can specify 'linear' when ordering
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Its not a 'linear' spring... their 'linear progressively wound' (Hyperpro raising rate spring)...
Each coil is spaced differently so as the spring compresses and releases, it's characteristics constantly change. When the spring is at rest all it's coils are available and it takes very little force for the spring to compress. As more force is added, more coils start to touch making the spring stiffer. The higher the force, the stiffer the spring
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details on the center of this page http://www.hyperpro.com/hyperpro/en/node/21 , and this is what you get with Hyperpro.
 
ST1100Y said:
Its not a 'linear' spring... their 'linear progressively wound' (Hyperpro raising rate spring
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Yes I have read that already,I am going to give them a try so I hope they will be worth the investment,I don't know whether to get genuine oil and dust seals or go for those saito ones you told me about from Louis,
wemoto also have a Kyoto brand aftermarket seal, the genuine ones are twice the price. someone said the dust seals rarely need replacing anyway.

If you are ever over in Ireland Martin I owe you a beer, thanks for your help,I will let you know what I think of the new set up in a few weeks when I have everything installed, and hopefully I am able to ride again by then if my foot has healed up ok.
 
I enquired directly with hyperpro in Holland and their answer is that they make just one spring for the st1100abs2 and it's a progressive spring.


I ordered the hyperpro's today from sportsbikeshop.co.uk, best price I could find,they include hyperpro 15wt fork oil with the springs,not sure if I'll go with that or the 10wt motul that I have already.
I have all the other parts ordered too,bushings, tapered head bearings,fork seals etc and the anti dive rebuild parts from davidsilver.
I hope to get it all installed next week,and hopefully my foot will be healed enough for a short ride,can't wait.
 
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I have all the parts ordered for the forks,but I won't have the fork springs from hyperpro for aroud 3 weeks,
can I fit all the other parts,and change the fork oil,and then just drop in the new springs when I get them?
can the new springs be fitted without removing the forks again,or should I wait and do all together?
 
broc11 said:
I have all the parts ordered for the forks,but I won't have the fork springs from hyperpro for aroud 3 weeks,
can I fit all the other parts,and change the fork oil,and then just drop in the new springs when I get them?
can the new springs be fitted without removing the forks again,or should I wait and do all together?
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I'd wait and do it all together, for a couple of reasons. First, changing from one spring to a different one will most likely have an effect on how much fork oil is displaced by the spring. So you'll want to fill the fork oil by measuring distance from the top tube, not by volume. Much easier to do that with the forks off the bike. Second, pulling the old springs out involves extracting a fair amount of fork oil which sticks to the coils as they are removed. This not only makes a big mess, but also changes how much oil remains in the tubes, so you're back to measuring the oil level again after cleaning up the mess. And that's just for the left fork, which is the easy one. Changing the spring on the right fork with it still on the bike is more difficult than doing it off of the bike.
 
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