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Discussion Starter #1 (Edited)
Over the next couple weeks I'm having my suspension redone by John Curea. John is pretty well known nationally for his work on dirt bike suspensions, but he's done work on street bikes too. He was also the suspension guru on ThumperTalk up until a year or two ago. I've used him a few times for work on my dirt/dual sport bikes and he's only 15 minutes from my workplace. I spoke to John a few weeks ago to see what he could do for my bike. He's going to revalve the forks (including a new piston) and install heavier springs and oil. For the rear, he's going to revalve the shock and install a heavier spring. He's also going to put the shock on the dyno before the work to get some baseline numbers.

My complaints about the stock suspension:

1) There is way too much fork dive when riding two-up (even with full preload), obviously from soft springs

2) The front is pretty harsh when riding into shape-edged bumps or potholes, with the infamous "thunk"

3) With the preload cranked all the way up in the rear, the action is a little harsh, probably from a lack of damping

4) There is too much rear sag for 2-up riding (even at full shock preload)

5) Ground clearance is limited for offroad riding (duh). I hope to get a little more by decreasing the amount of sag.

So my goal is to correct these issues without spending a fortune. I bought my Wee used and it didn't cost me a lot. I can't justify spending 40% of the bike's purchase price on suspension upgrades. I told John I want the best bang for the buck so that's what we're shooting for. I plan to post up some results here once I get the suspension parts back. I'm dropping off my forks tomorrow for phase I.

In case anyone wants to know, my bike is a 2004 DL650 with 3,200 miles. In the past 2 weeks I've added all the farkles I feel are necessary to make the DL a good dirty-adventure bike. I did this so that my rear sag numbers would not be influenced by the weight of adding more farkles later. I'm 6'3" and 220 lbs. My favorite riding is dual-sport/enduro. My other bikes at this time are a street legal Husaberg FE570 and a plated KTM 250exc. Prior bikes have included a KTM 950 Adventure, a KTM 450exc, a DRZ400S, an '03 FZ1, an '02 ZX6R, and a VX800.

Here are pics from a ride last weekend to give you an idea of some of the trails I've ridden the Strom on:













 

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For that kind of riding, (off road, Fire / National Forest Service roads) good suspension makes such a difference. It does as well for aggressive street riding of course.

I went the spendier route with Race Tech fork mods, heaver springs and the Elka Shock. Huge different in handle the bump, ruts, washboard especially when pushing it. I'm not an real aggressive off-road rider (or street) but the better handling makes it easier to do so.
 

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Discussion Starter #4
I dropped the forks off Monday during lunch and should have them back tomorrow. I'm hoping to ride the bike up to the Allegheny National Forest (Rocky Gap and Marienville, PA) this weekend for some trail riding. I'll post some comments about the upgrades when I get back. John said he'll take pictures of the internals while he's doing to work, so hopefully I can post those up too.
 

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These kind of suspension upgrades make a nice bike a great bike.

Rich Desmond makes Sonic Springs, and is a well-known suspension guru in the SV and DL communities, another great resource.
 

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Discussion Starter #6 (Edited)
Yeah, after researching this forum and ADVRider, my original plan was to go with Sonic fork springs and RT fork emulators, along with a Sasquatch shock rebuild and new spring. However, after talking to John, this may be a much better value. John also told me that the piston he's installing in the forks will provide better rebound control, which the emulators can't do. Plus, I prefer doing local business when I can. To seal the deal, John is one of the best suspension tuners in the country.
 

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Piston in the fork would mean a cartridge is being used. Either he is doing a major conversion to a much better damping system or he doesn't realize the 650 has a damper rod fork and is in for a rude surprise.
 

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Discussion Starter #8
Piston in the fork would mean a cartridge is being used. Either he is doing a major conversion to a much better damping system or he doesn't realize the 650 has a damper rod fork and is in for a rude surprise.
No, he definately knows it's a damper rod fork (as our conversation about emulators indicated). He did say he's installing a piston of some sort. I'm used to cartridge forks, so these valving upgrades are new to me. As long as it works I'll be happy :mrgreen:
 

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Unless he means a cartridge emulator, a piston would involve a conversion to cartridge. Traxxion Dynamics is the only outfit I know of that does that.
 

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Discussion Starter #10
Unless he means a cartridge emulator, a piston would involve a conversion to cartridge. Traxxion Dynamics is the only outfit I know of that does that.
Not true. I went over to the shop this evening and John showed me what he's doing. His valving piston design is proprietary, so that's why you -or anyone else for that matter- have never seen it. He developed it about seven years ago as a solution to offer not only better compression damping, but also additional rebound damping (besides the damper rod) that you can not get from a cartridge emulator. In his opinion, emulators are "old '80's technology" and overpriced for what you get. Because they are essentially a one-way check valve, they can not offer any damping when the fork rebounds (fluid just rushes past the valve in that direction).
 

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Not true. I went over to the shop this evening and John showed me what he's doing. His valving piston design is proprietary, so that's why you -or anyone else for that matter- have never seen it. He developed it about seven years ago as a solution to offer not only better compression damping, but also additional rebound damping (besides the damper rod) that you can not get from a cartridge emulator. In his opinion, emulators are "old '80's technology" and overpriced for what you get. Because they are essentially a one-way check valve, they can not offer any damping when the fork rebounds (fluid just rushes past the valve in that direction).
That sounds pretty cool. What will a rebuild like that cost?

If ya don't mind my asking.
 

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In his opinion, emulators are "old '80's technology" and overpriced for what you get. Because they are essentially a one-way check valve, they can not offer any damping when the fork rebounds (fluid just rushes past the valve in that direction).
There are many things I haven't heard of. A one way valve is involved because compression damping needs to be a lot lighter than rebound damping. The problem with the rod is getting the compression damping light enough since the oil still needs to move inside the rod. I agree with his opinion on emulators. Maybe his solution allows oil to pass without all of it going through the damper rod. That would be great. A good emulator will have a check valve to increase the damping on rebound but open on compression, not letting oil rush by on rebound.
 

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Discussion Starter #13 (Edited)
Maybe his solution allows oil to pass without all of it going through the damper rod. That would be great.
Bingo.

I can't wait to see how it works in the real world.

BTW, I asked about drilling holes in the damper rod and he feels it's a waste of time. Without something else to control the oil flow (like a piston or emulator), the damping will only be good in one particular situation (i.e., type of impact), and be poor everywhere else.
 

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Subscribed...looking for a better ride
 

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Discussion Starter #15
Subscribed...looking for a better ride
Is that Engineer Pass in your avatar? I was up there last year. Awesome place!

I got the forks back and installed them this evening. I should have an evaluation of the weekend ride posted up on Sunday. My ride will include lots of twisty pavement, gravel roads, and 2-track trails (rocky and groomed) so it'll be a good test of all the terrain the Strom is capable of. I'm camping so I'll be hauling some gear too.
 

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Discussion Starter #16
That sounds pretty cool. What will a rebuild like that cost?

If ya don't mind my asking.
John cut the stock fork springs (for the rate we were shooting for) and then cleaned them up (lathed, deburred, reshaped the ends, etc), cut new spacers, installed his damping piston and shim stack, ran everything in the parts cleaner, reassembled the forks, and filled them with Motorex 20wt fluid. All that for $175.
 

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Subscribed. You are of course opening a can of worms - is he remotely prepared for an onslaught of Stromtroopers looking for a better suspension?
 

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Is that Engineer Pass in your avatar? I was up there last year. Awesome place!
Good eye, yes that is Engineers Pass. That was last year. The Wee likes to explore! I spent a week camping all over that area. :thumbup:
 

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Discussion Starter #19 (Edited)
I just returned from a 30 mile ride of 50% twisty pavement, 30% rough chip-n-seal road, and 20% gravel. John set the preload adjusters all the way out and told me to ride it like that for a while before adding more preload. The improvement in front-end dive while braking or decelerating is dramatic. That alone is worth the money spent IMO. I didn't get a chance to ride 2-up yet, so I'll have to post on that later. That'll be the real test of dive control.

The bike feels good on the rough roads. I did not experience harshness at any time, and it actually feels smoother than before. There is no wallowing (i.e., lack of damping for the heavier rate springs). I also ran up and down a grass field pretty aggressively and it felt rather smooth. I placed a zip-tie on a fork tube and there is about 1/4 of travel left before the forks bottom. I'm certain I would have bottomed the stock setup for as hard as I was ridding that section.

Tomorrow is the offroad test.
 

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Watching this thread keenly. I am a light weight 150 lb. rider and am still close to bottoming out the stock forks. I as well ride fire roads/trails aggressively. My zip tie indicator shows one inch from the top and with a super brace on that leaves about 1/8 of an inch to hitting the break line mess.
Just trying to follow all the old threads on the shocking mods to emulate but it is intimidating. Its getting me all wound up. Some one who understands the options could compress it all into one thread. OK enough puns.

I look forward to the ride report and pics.
 
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