Shorten fork 1 inch

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I have shortened the rear of my ST1100 (ABS II) approximately 1.65 inches; 1.25 inches with a shorter works shock and approximately .4 inch with a 60 series rear tire.

I slid the forks up in the triple trees 3/4 inch. That lowered the front approximately .65 inch. If I could shorten the fork 1 inch the front and rear would be in balance. Shortening the forks 1 inch would lower the bike only .88 inch, but that should be enough to get it pretty close. If I decided to go back to the stock tire I could simply alter the forks.

I spoke to the nice folks at Traxxion, and they could do the job for $500. I'm not sure what all that includes. The problem is that I would have to separate the forks from the bike and ship to them, or take the bike to Atlanta.

I have a pretty good independent mechanic locally who used to work for a dealer. If I got the parts and gave him instructions on what to do I'm sure he could do it.

I like a soft ride, so I am hoping to keep the stock springs, cut any spacer, replace the fluid, and bushings.

I need to give him directions on how to cut the spacers, how much fluid to put in each fork (ABSII), what weight of fork oil to use, and what bushings to replace. My bike is an 00 ABS II.

Does anyone have any ideas?
 
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Before paying $500 to have the forks permanently modified, have you experimented with changing the ride height with different size spacers in the forks?

Also, seems like a lot of trouble for an additional 1/4" difference, since you already have them 3/4" up in the tree. I'm not sure how much difference 1/4" is really going to make.
 
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jspringator
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I have never see these forks. Are there spacers they can remove? Im going to be lowering the forks an inch. That will lower the bike .88 inch. That plus the forks will be fairly close to 1.65 inch.
 

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I have never see these forks. Are there spacers they can remove? Im going to be lowering the forks an inch. That will lower the bike .88 inch. That plus the forks will be fairly close to 1.65 inch.
Just get thicker boots? :think1:
 

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I am a munchkin, 5'6" 26" inseam. I had Spencer lower my seat an inch and put in LD foam. I think that was less than $100
 
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jspringator
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I've already lowered the back. I'm just trying to get the front and rear to match.

I have a RDL. Great seat.
 
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I just re-read your original post and now I realize that what you want to do is lower the front an additional 1" over the 3/4" you already have, missed that first time, thought you wanted 1" total.

Yes, there are preload spacers in each tube that are the normal way of adjusting ride height. If you shorten the spacer the bike sits lower, but if you shorten it too much your available fork travel decreases and you may bottom it out over big bumps. There's really nothing to lose by experimenting with shorter spacers, you can make them out of 1" PVC pipe. I think you're probably OK going with 1" shorter spacers, plus the 3/4" you already have with the tubes dropped. You will lose 1" in available fork travel, but according to the service manual there's 5.9" of travel, so you'd have about 5" instead.

Also, if you think about it, if you're considering having the tubes shortened by 1" you're going to have to shorten the spacers by 1" to keep the spring preload the same anyway. So you can try the 1" shorter spacers first in the full length tubes, and if that 1" loss in available fork travel is problematic, then have the tubes cut down 1" and use the same spacers in the shortened tubes.
 
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Okay I have to ask. What is you goal in lowering the bike? I can think of many reasons not to lower it.

My wife had a 2000 ST1100 and she is 5'4" and was able to handle it in most situations. We did cut down the Corbin seat that came with the bike, we took almost 2" out of the saddle. She still was tippy toe while on the flat. Roads canted the wrong way did present issues. At the end of the day we got her a different bike that better fit her and her riding needs.
 
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My first thought when reading your post was why do you need to get the front lower? do you need the lower height to make it easier to touch the ground or is the bike displaying ill manners because you have changed the geometry. Or, do you feel that you have to mimic what you did on the rear? The reason I ask is because if you are thinking you have to lower it the same on both ends, that isnt always the case. By lowering the rear more, it will decrease the rake angle of the forks and give the steering a slightly slower feel and more straight line stability. I would be more concerned with having the front lower... this would make the steering twitchy. But , the amount of difference your talking about is minimal and you may not notice any difference in handling.
 
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jspringator
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I was just trying to make it even on both ends. I don't need it any lower. If it isn't going to make any difference I may leave well enough alone.
 
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jspringator
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Okay I have to ask. What is you goal in lowering the bike? I can think of many reasons not to lower it.

My wife had a 2000 ST1100 and she is 5'4" and was able to handle it in most situations. We did cut down the Corbin seat that came with the bike, we took almost 2" out of the saddle. She still was tippy toe while on the flat. Roads canted the wrong way did present issues. At the end of the day we got her a different bike that better fit her and her riding needs.
Best thing I ever did was lower this bike. It is a lot easier for me to handle. And I've still got the bike.
 
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I was intimidated by putting in gold valves (which means pulling the forks) on my 1300. Honestly, it turned out to be one of the easiest maintenance projects on my bike that I've done once the tupperware was off. Pull the front wheel, take off the fenders and remove the bolts holding the brake lines, then upper and lower fork clamp bolts and they slip right out. Since you will be putting in a shorter preload spacer (my stock spacer was 8" long) you will be cutting an 1 1/4" pvc sink tailpiece - a piece of cake. Then compressing the spring and putting the cap back on will be easier. If you do it yourself, pick up one of those syringe fork oil fillers - it makes the job a snap. I don't know how the 1100 setup compares to the 1300, but it might be similar enough that my experience is what you will encounter.

The only fly in the ointment will be if you compress the forks an additional inch, you have lost that inch, plus your original sag (on my bike about 2" and I weigh 170 geared up). So, you will have lost about 3" of the 4" available travel (I'm using Dave's number from his earlier post). I would think cutting the shock down will require shortening the damper rod inside as well as the tube - certainly doable, but expensive. Again, I'm using my 1300's experience an an 1100 might present other problems.
 
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You can push the forks up into the triples further but at some point some hard part will hit the underside of the triples e.g. the mudguard or the fork leg tops. Travel of forks is controlled by the bottoming stops, and the extension is controlled by top-out springs engaging with either the bottom of the fork tubes (damper rods) or between the top of the rebound valve and the inside top of the cartridge. To reduce the travel of the forks, you need to change the point at which the top-out springs engage to limit the extension, either with a spacer or a longer spring. On the cartridge damper that is inside the damper on top of the spring, and on the damper-rod leg that would be be below the top-out spring on the damper rod. In either case a simple metal sleeve of a suitable diameter should suffice. You would perhaps need to increase the spring rate a little (so that at full shorter compression the same force is needed to prevent bottoming as the original length).
 
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To reduce the travel of the forks, you need to change the point at which the top-out springs engage to limit the extension, either with a spacer or a longer spring.
correct me if I'm wrong, but this would only be true if the forks didn't compress at all under the static load of bike plus rider, and the fork travel started out in contact with the top-out spring. In practice that isn't true, the fork travel starts out slightly below the top-out spring, depending on how much sag is set. Which brings up a question, does Honda spec the fork travel from the top-out spring, or from the static sag start point with the factory fork settings? Next question is what would be the benefit of using a longer top-out spring?
 
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jspringator
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You can push the forks up into the triples further but at some point some hard part will hit the underside of the triples e.g. the mudguard or the fork leg tops.
I know 3/4 inch works and don't want to push it. After thinking about this I may be lower with my current setup, accounting for sag on stock 50,000 mile 17 year old springs, than with proper springs an inch shorter.

I remember when I pushed the forks up an extra quarter inch and it felt like the bike lost 100 pounds.
 

ST Gui

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I was just trying to make it even on both ends. I don't need it any lower. If it isn't going to make any difference I may leave well enough alone.

Keeping the bike 'even' by lowering the front and the rear generally maintains the prior handling characteristics but may affect ground clearance which may effect on handling depending on a given rider.

The ST1300 is faster handling than some other bikes and slower than others. Lowering the rear or raising the front slows down the handling. Raising the rear or lowering the front speeds it up.

Not that either of those is unilaterally a good thing but can be depending on what the rider is wanting to accomplish.

I'm betting that if you did lower it that you'd probablyfeel the difference based on what you've posted. The question is— how does the bike handle for you as is? Lowering it will make it handle faster? Is that something you want? I don't know where that puts you with its high-speed stability compared to stock. Faster handling than factory isn't for me.


jspringator said:
Best thing I ever did was lower this bike. It is a lot easier for me to handle. And I've still got the bike.
Lowering the front means making it tougher to put it on the center stand and could make the sidestand unusable in most situations. I may have missed it or forgotten— did you shorten the side or center stand(s)?
 
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I took an inch and 1/2 out of the sidestand. It takes 2 to get it on the centerstand, although a 2x6 under the rear tire would make it a one man job again.

It handles very well on the highway up to the mid 90's, the fastest I've gone. It does take work to throw around in the twisties. I was hoping to make it go into a curve easier with less work, but I can live with it the way it is. It has never scraped or even come close as far as I know. The centerstand scraped when it wasn't properly seated because of interference from an exhaust bolt. Once I fixed that, no problem. The tire installer removed the exhaust to change the tire and didn't put it back on right.

Honestly, It is hard to see a downside to lowering the bike, except use of the centerstand. And I lowered it a lot (1.65"). I had to spend some of that height on a Russell seat, but it was worth it. I don't think the bike is topheavy so much as heavy and tall. When the height is reduced it is just heavy. Heavy is easier for me to deal with than tall. Lowering the bike has to taken in the context of the alternatives. I could have just sold it and bought a CTX or cruiser. Any replacement would likely have more ground clearance problems than a lowered ST1100. These bikes really aren't worth anything, so it is more cost effective to mod what you have than replace it. Since Works has gone out of business, I guess the lowering shock option is over going forward.
 
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correct me if I'm wrong, but this would only be true if the forks didn't compress at all under the static load of bike plus rider, and the fork travel started out in contact with the top-out spring. In practice that isn't true, the fork travel starts out slightly below the top-out spring, depending on how much sag is set. Which brings up a question, does Honda spec the fork travel from the top-out spring, or from the static sag start point with the factory fork settings? Next question is what would be the benefit of using a longer top-out spring?
You quoted the correct part of my post "to reduce the travel". That is what spacers or longer top-out springs will accomplish, where I would define travel as the full range of fork movement from topped out to fully compressed. The spacers also "shorten the fork" which is what the PO was seeking.

Reducing the preload on the main spring or changing the spring length will change the ride height. It depends what you want to achieve. Just putting softer or shorter springs will change the ride height but would not be my choice for control as there will be a point after an extension (e.g. riding across a dip) where the fork will be in free-fall with little or no spring to absorb chassis energy. Using a top-out spacer keeps the fork under control throughout the full range of movement, and allows the use of a correct spring rate to keep the static ride height at around 1/3-1/4 of the full travel. I'm coming at this from the perspective of someone who likes to corner hard on even pavement, and someone who is happy touring around in a straight line will have different priorities.
 

ST Gui

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jspringator said:
Honestly, It is hard to see a downside to lowering the bike, except use of the centerstand. And I lowered it a lot (1.65"). I had to spend some of that height on a Russell seat, but it was worth it. I don't think the bike is topheavy so much as heavy and tall. When the height is reduced it is just heavy. Heavy is easier for me to deal with than tall. Lowering the bike has to taken in the context of the alternatives. I could have just sold it and bought a CTX or cruiser. Any replacement would likely have more ground clearance problems than a lowered ST1100. These bikes really aren't worth anything, so it is more cost effective to mod what you have than replace it. Since Works has gone out of business, I guess the lowering shock option is over going forward.
+1 Great post especially the above and especially[SUP]2[/SUP] the bit I emboldened. The new Wing has a lower seat height and fits me better than the ST. I'd consider lowering my ST a little if possible.
 
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