Upgraded suspension finally!

Well, I pulled the trigger on a right side cartridge fork from a 2000 this morning. Got it for $55 free shipping off of sleazebay. I'm gonna get it apart so I can wrap my head around what the parts actually look like, and how it works. I'm sure I'll have some more questions for ya pretty soon, if you don't mind....

Frank

Bueller said:

Well, I pulled the trigger on a right side cartridge fork from a 2000 this morning. Got it for $55 free shipping off of sleazebay. I'm gonna get it apart so I can wrap my head around what the parts actually look like, and how it works. I'm sure I'll have some more questions for ya pretty soon, if you don't mind....

Frank

Click to expand...

No worries, I'm happy to help if I can. Did you get the fork cap with that damper? If not you will need to source one from somewhere, as the stock left leg cap has no threaded socket. Something like this:

http://www.ebay.com/itm/1991-Honda-ST1100-Right-Upper-Top-Fork-Tube-Front-Suspension-Cap-Top-Lid-/161259341109?hash=item258bce4535:g:0yQAAOxykmZTMaxT&vxp=mtr

Yea, the fork is coming complete as a sealed unit.

If I understand correctly, you sourced both aftermarket rebound and compression pistons from Daugherty's along with the shims that all fit inside the stock cartridges. Doesn't look like they sell them on separate on the website unless they do the service, so you apparently have the brother-in-law hookup, lol.

I've been poking around on the interwebs, and found several places that have the shims. I am assuming that the racetech, traxxion, etc. pistons fit inside the cartridges?

I appreciate your willingness to help btw...this is good knowledge for me, cause my Buell and my Harley have cartridge front ends as well....

Frank

I don't have any specific knowledge of Traxxion parts but the 20mm i.d. cartridge/ 10mm OD shaft is a very standard size so they will undoubtedly have parts to suit. If you follow the specific shim stack recipes in the RT instructions, you won't go wrong, and any brand of shim of the correct dimensions could be used.

If you know what you want, I'd certainly try Jamie for the parts, he's been good for me to deal with. I've bought springs, valves, shims and a shock from him over the last two years. He can be a little slow to respond occasionally but he's an honorable guy, and very highly rated by VFR riders for his model specific knowledge.

At about 90,000 km (Spring 2016) I replaced original OEM parts with Progressive springs in the front and the 465 shock on the back + a heavier oil. Much improved ride. As the OEM parts were just plain worn out I've no idea to what extent the Progressive parts improved performance vs. installing new OEM parts but I hear and read that the 465 series shock is much better than OEM.

As others have commented to TerryS that is one super video with a nice twisty road, great engine sound and a skilled rider.

Yea, on mine, the 465 by itself made enough difference from the stock shock that the front end actually spooked me just riding it around the block. I just wanted to see how much difference it made changing one end and not the other. Definitely don't recommend going that route, lol

Frank

My ST1100 had already had progressive springs fitted in the front when I bought it in 2014 but the rear although looking good felt a little wayward. After a long tour to Portugal it was very soft but no sign of leaks or spring damage.
I got a good deal (I think) on a NOS rear shock from Silver's. WOW, the difference was immidiate and the ride and handling were superb (for a big heavy wobbly old thing, but that's enough about er'indoors). I suppose nearly 20 years and 50000 miles take there toll.
My bike is non ABS and the replacement NOS all seem to be ABS, all the better for it though.
Upt'North.

Hey terry...I'm suspecting that you changed the valves out at same time that you put in the cartridge the first time around? I'm kind of planning to install without new valves starting out, just to get a reference point. Looking back at previous posts you mentioned beefing up the shim stack on the compression side. Do you have a pseudo-educated guess on how many shims to add?

The other question I had was on preload. I'm assuming you checked it when you were going together. Do you think the loss of the damper rod is going to soften it up quite a bit? Am planning on cutting my spacer down to what the right side is now, cause I kept it proportional to how much I added on the left side.

Frank

Hi Frank

Yes I changed the shims over to C32 and rH16 in both sides when I did the damper installation.

For the spacers, you should be compressing the springs by about 15mm when the fork is assembled. With the fork tubes compressed, put the spring and two flat washers in, then pull the damper rod up to full extension with the lock nut and fork cap fitted as normal, and holding the cupped washer in it's usual place under the locknut. Now measure from the top of the washers on the spring to the underside of the cupped washer, then add 15 mm to that length and that will be the spacer length that will give 15mm of preload.

Ok, so you tried the C32, and rH16 stack ups with the factory pistons? Does the 15mm preload give you the 35-37mm sag that seems to be the general consensus?

Frank

Interesting read for those following along..

http://www.dvosuspension.com/blog/shims-what-do-they-do/

Frank

Bueller said:

Ok, so you tried the C32, and rH16 stack ups with the factory pistons?

Click to expand...

Yes that is right, but I now have the Daugherty pistons in there. The factory piston (compression especially) has too much free bleed area (the little notches in the sealing faces) which allow more free movement (looseness) than I think is needed.

Yesterday I pulled my forks down and increased the free bleed size in the rebound to 1.3mm dia, which also matches the size in the compression valve, as the 1.0mm hole previously was just a little harsh. As part of the experiment I also increased the rebound shim stack to rH19, as I found RT instructions which suggested these for the ST13. I took a quick ride today and the change is noticeable with a better response to bumps, you feel them but there is no jolt, and handling is solid, so that is pretty close to optimum I think.

Bueller said:

Does the 15mm preload give you the 35-37mm sag that seems to be the general consensus?

Click to expand...

I do get around 38mm; I figure for the long travel (150mm) ST11 fork, it probably should be at the upper end of that scale. I also set the oil level to 130mm and that has firmed up the bottoming resistance a little which feels good.

The sag that you get will depend on your weight and spring rate. Probably best to cut the spacers a little longer and try them, as you can easily pull them out and shorten them if needed with the forks in the bike.

Got my fork the other day and got it all apart. Been educating myself as much as possible with what's available on the inter webs. Now just trying to figure out what shim stack to go with. Was gonna try to go with what you had in yours at first, but I think its probably better to go a little firmer because of our weight difference, and I ride with a passenger quite a bit. According to the race tech compression formula chart for my situation, I should go with C36. The problem now, is figuring out the rebound stack since you have to actually 'buy' the race tech valve to get the key to access the DVS on their site. Since I have more time than money at this point, the stock valves will have to do right now. I think I might start out with rH21 and see how it feels, along with 140mm, and 10w for a baseline. It should be a drastic difference from how it feels right now, between going from a damper rod and cartridge to 2 cartridges, different stack, and less fluid. The only thing I'm keeping constant if I go this route, is the 10W which is probably a bit heavy for the cartridges. It's definitely not a scientific approach since so many things are changing at once.

For posterity, the stock stacks are:

Compression- Rebound-
.10x17 (2) .10x17(5)
.15x17 .15x17(3)
.15x15 .15x15
.40x12 .20x9
.20x10
.20x9

Race tech numbers:

Compression (C36)- Rebound (rH21)-
.15x17(6) .15x17(10)
.10x15 .10x15
.10x13 .10x12
.10x12 .10x9
.10x11
.10x10
.10x9

It's worth noting that all they change from stack to stack is the number of face shims. The supporting stack stays the same compression and rebound respectively.

Thoughts?

Frank

(As a side note, there is this-http://www.shimrestackor.com available for $. Thought about it/still thinking about it, although I think it gets too in depth because there's parameters that may be hard to obtain by us mere mortals)

When I first started playing with shims and bought compression gold valves, I too was intrigued to learn that the only change between stacks was the number of face shims. Makes it relatively easy to go firmer or softer.

Also of note is that the standard recommendations (for Gold Valves, for the ST1300), is C34 and rH19, with a note that C32 provides a more touring-oriented set-up. I think you will find C36 a bit jolting especially with the higher spring rate that you have. I have tried C31 to C33, and 32 is my sweet spot in all my bikes.

I did have rH18 with my stock rebound valves and that was pretty good for me, but I'm now using rH19 with the new valves. I'd say that I have a lot less sensitivity to a rebound stack change than to the compression (i.e. I can't tell much difference).

As you are retaining the stock valves with quite large bleeds, a slightly stiffer stack would probably be better for you.

Yea, I'm concerned that C36 may possibly be a bit harsh too. That's my major issue right now is harshness on high speed big bumps with the stock setup. I'm sure the fast/squared rebound has a lot to do with it too. Maybe I'll try C33 and rH20 instead...aargh..decisions, decisions lol! I still gotta order the shims, so there's still time to ponder it, I guess. Although spring is right around the corner, so I better get it figured out!

Frank

It's your call, but as I have suggested before, the baseline RT settings are a good starting point, so I'd suggest C32 and rH19 for you.

Once you've had the forks apart the first time, the next times(s) will be easy!

90 minutes is my best time to make changes, ride-in to ride-out.

Ended up buying shims from SDi (suspension direct). They were the cheapest at $.89/piece BUT they absolutely rape you with a $17 shipping and handling charge! They could of sent them all in an envelope, but instead shipped them in a big arse box. Ok, off the soap box...

Went ahead, and re-stacked with C32, and rH19. Oil level at 135mm with 10w Maxima oil. Left the aluminum cap off, because as Terry stated, it won't fit into the recess on the bottom of the slider. As an experiment, I marked the left damper fork tube with a sharpie 1" above the dust seal, put the fork on a block of wood and on a weight scale, and compressed down to the mark. It was just under 100 lbs. Did the same with the cartridge side and a 3.5" spacer, and ended up being the same. Should still have the 1.5" preload I had before, but haven't been able to check it yet.

Just bouncing on it in the garage, it felt once again, dramatically different. After I get my fuel tank leaks fixed (Bad sender o-ring), I'll re-report on how it feels actually riding it. The process itself is cake. I did have to grind a couple of threads off of the bottom sealing bolt, because it would spin the rod without getting tight. After looking at it, it turns out that since the factory uses more shims that are thicker than what I installed, the bottom sealing bolt bottoms out against the compression piston bolt. A die run down on the bolt, and a couple minutes on the grinder, and it was all good. Stay tuned.

Frank

Finally got to go on about a 80 mile test ride. The changes made a BIG difference in several ways. First thing I noticed, was that this new setup makes small bumps nearly non existent. They can barely be felt. The larger bumps are still...well larger, but it seems like they're smoother. Kind of like instead of having a perpendicular line at the beginning and end of each bump, to having a ramp up and over each bump. The next thing could be considered more of a negative, but I got some of the fork dive back. Kind of expected that, since the anti-dive system was disabled. It's still not bad, and defenitely way better than stock was although the spring had resolved most of that the first time around. Now the most drastic change has happened in the corners. It's a totally different ride in the corners. It's like the bike already knows what to do when you enter the corner. I can take a corner 10-15 mph faster than before and not get nervous about it.

All in all it was worth the $100 investment ($55 for the fork, $45 for the shims) and time. My novice opinion is that there is still some room for improvement, wether that consists of fork oil weight/level, shim stack combo, or different rebound-compression pistons. I'll prolly ride it this season and get a good feel for it before deciding on what changes to try next.

Anyone considering making the mods, I say just do it!

Frank

Great result, Frank! Well done.

I think that some or most of the fork dive that you have is due to the large bleed area on the compression valve; this is where some of the ST's plush ride comes from as well, but as I understand it, dive normally occurs at a velocity below that which would open the shim stack, so most of the dive is controlled by the bleeds. If you were interested in an irreversible trial, I'd suggest taking the compression valves out, and filing the bleed slots off on one face so that you only leave three slots on the other face. I have valves (stock, out of a GSXR or something I think) just like that in my VTR1000 and it works really well.

For reference the drilled bleeds in my DMr compression valves are 1.3mm diameter.

Personally, I don't mind a bit of dive as long as the forks don't bottom out under brakes over bumps.

I thought about the bleeds maybe bleeding too much after I wrote my post. It does make sense to file the bleeds down. I'll try it next time I'm in there. Plus it's free! It's really not bad though. Just a whole lot different coming from the damper rod/anti-dive. It 'may' have only compressed 1/2" before, lol. I'm happy with it.

Now I just gotta get my new progressive shock damper figured out. Their instructions suck! The way it reads, it says not to go from setting 1 straight to 5. In my mind that means you can turn it 1-2-3-4-5 and BACK 5-4-3-2-1. Apparently that's not right. They should of said, "turn adjuster clockwise ONLY." Why would you make an adjuster so flimsy in the first place? Crap I'm ranting again! I'm not sure I wanna pay $80 to ship my 'new' shock back to them for warranty since they'll probably blame it on operator error and not fix it anyways...

Frank