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Discussion Starter #1
OK, so I installed the R6 shock yesterday without much drama -- the most difficult part was getting the washer shims to stay on the eye of the lower mount when inserting the bolt. But, anyhoo, everything buttoned up properly.

So now it's adjustment time, and I need a little help here. The preload is obvious. But I do have a question about the top (compression, I assume) adjustment -- that little slotted screw head. Turning left makes it softer, right? And the bottom knurled wheel adjuster (rebound?) -- which way does what?

As you can see I'm pretty uninformed about these things. On past bikes I just fiddled with the preload, or on Harley and Goldwing added air pressure to taste.
 

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Mike, The R6 owner's manual page that explains damping adjustments for the shock is on page 8 of this thread from the RCForum.

Shock Swap with 99-02 R6

Briefly:

Rebound (bottom adjuster)
Anti-clockwise (viewed from above) increases damping, clockwise decreases. 25 click range min-max. Standard setting is 9 clicks out from closed position (fully clockwise)

Compression (top screw)
clockwise turn increases damping, anti-clockwise decreases
13 click range min-max from fully anti-clockwise position
Standard setting is 7 clicks out from fully closed

I set mine on the standard settings just to try it and found that those setting were just about right. I have not felt the need to alter those settings since, but it is nice to have that option. The R6 shock does not work miracles but it is a HUGE improvement over the OEM part. Fitting the R6 shock is a very good move you will certainly not regret.
 

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..I set mine on the standard settings just to try it and found that those setting were just about right. I have not felt the need to alter those settings since, but it is nice to have that option. The R6 shock does not work miracles but it is a HUGE improvement over the OEM part. Fitting the R6 shock is a very good move you will certainly not regret.
By the sound of it you fit it with the R6 spring in place? Or did you get it rebuilt and resprung with the correct spring for your weight?
 

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The stock spring on the R6 shock is the incorrect length and ratio . Ideally you replace it with a Racetech spring . You should find a tread about all this here on the forum : better go over to the RC390 forum . Matt from formula390 is a great guy and he did all the research and can supply you with all the parts you need to do the conversion properly
 

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Johann, If you are interested in the R6 shock conversion, please read the thread I posted above lifted from the RC Forum. It details the search by Matt of Formula390 for a suitable replacement shock for the 390, the genesis of the conversion and the spring requirements for the shock to work correctly on the 390.

On the R6, the shock works through a lever which increases leverage, but on the 390 the shock works directly between swingarm and frame. The stock R6 spring (rated at around 8-9 kg/m) is too light for the direct application (although a few 390 owners have used the R6 shock with the stock spring). To get the correct sag and performance it is really necessary to swap out the stock R6 spring for a higher rated (10-12 kg/m) spring, tailored to the rider's weight. Mine took an 11.6 kg/m spring from RaceTech, along with a screw-type preload adjuster to replace the ramp-type adjuster that comes on the R6 shock. The conversion also requires a set of bushings and shims to adapt the shock's lower eye to the 390 swingarm mount. The end product is a very competent shock, with complete compression-rebound adjustability, that fits both 390 variants perfectly and is light years ahead of the OEM shock in performance. Total cost for the conversion was about $230, if I recall correctly. The shock is easily rebuildable, but mine performs perfectly without being rebuilt. A rebuild can wait for a future date if needed at all: or another R6 shock can be had cheaply from eBay. For anything short of full-bore racing, this is an excellent shock for a fraction of the price of an Ohlins/JRi/Wilbers/Etc.
 

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Discussion Starter #7
Got out on it today and cannot believe the difference. I deliberately sought out some of the roughest (paved) roads around my house, and the durn thing felt like a gen-yoo-wine touring bike. Even hit a big frost heave that should have heaved me off the bike but got over it with surprising grace. I know many of you have fiddled with different spring rates and things like that which, I am sure, would improve things even more. But on the theory that if it ain't broke don't fix it I'm going to stick with this R6 shock in OEM trim.

Now about those forks.....:D
 
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Johann, If you are interested in the R6 shock conversion, please read the thread I posted above lifted from the RC Forum...
I'm on page 19 of that thread already, my question was more asking what YOU did? Did you buy a complete or kit from formula390.com? Did you buy a shock from eBay? Did you replace the spring?
 

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Johann, I bought the R6 shock off eBay for about US$35. I took off the stock (yellow) R6 OEM spring and replaced it with parts I sourced from Matt at Formula360.com. Matt is, among other things, a dealer for RaceTech and Tyga, and he was able to supply all the necessary parts to upgrade the shock and customize it for my weight:
--Racetech spring
--Racetech screw-type preload adjuster
--12>10mm bushings (2)
--shims (2)

It is very convenient to buy all the needed parts from a single source.

Matt is also able to rebuild the R6 shock if this is needed. Mine did not need a rebuild.
If you are interested in this shock conversion you might want to just buy an R6 shock off eBay and try using it with the OEM yellow spring. In that case you would need only the bushings and shims, which you can surely find locally. Mikebet has just done this and, even though it is not ideal, it seems to work for him. If you try it and find the OEM spring too wimpy, then you can respring the shock.
 

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Discussion Starter #10
I'm on page 19 of that thread already, my question was more asking what YOU did? Did you buy a complete or kit from formula390.com? Did you buy a shock from eBay? Did you replace the spring?
Based on my post above you can see that I'm quite happy with the OEM R6 shock, spring and all. You may want to try one in stock trim before modifying it...you can always do that later if desired. I expected a marginal difference, if that, but this one gives a better ride than I could have hoped for with a bike this light.
 
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..Formula360.com. Matt is, among other things, a dealer for RaceTech and Tyga, and he was able to supply all the necessary parts to upgrade the shock and customize it for my weight:
--Racetech spring
--Racetech screw-type preload adjuster
--12>10mm bushings (2)
--shims (2)...
I'm pretty sure its Formula390.com? Anyway, the thread has info on spring specs to order, so I can do that from a local trusted supplier. The rest of the bits I may source from Matt, or may even look locally for bits that'll do the job. I think I'll get a shock from eBay and see how I go!
 

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Based on my post above you can see that I'm quite happy with the OEM R6 shock, spring and all. You may want to try one in stock trim before modifying it...you can always do that later if desired. I expected a marginal difference, if that, but this one gives a better ride than I could have hoped for with a bike this light.
MB, would be very useful if you could give us an idea of your weight and also if you could update your impressions once you have put on a few more miles.
@YesEvil was happy with the stock R6 spring (thread HERE) but only weighs 70kg, a weight I would need drastic surgery to get near.......
 

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I think the RaceTech upgrade components - spring and preload adjuster - are excellent, but a bit on the expensive side. I'm sure an appropriate spring can be had for less from a number of sources, in UK or elsewhere, and the R6 shock's OEM preload adjuster is serviceable. The OEM spring appears able to function OK for those on the lighter end of the spectrum, but even if you have to respring the shock, the whole operation can be done for a very modest sum if you are resourceful. It's hard to think of any other upgrade with a better cost/benefit ratio than the R6 shock conversion. The trick is to find a good used shock on eBay.
 

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Johann, Sorry for the typo. You are right, Formula390.com
 

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Discussion Starter #15
MB, would be very useful if you could give us an idea of your weight and also if you could update your impressions once you have put on a few more miles.

@YesEvil was happy with the stock R6 spring (thread HERE) but only weighs 70kg, a weight I would need drastic surgery to get near.......
Well, I'm no featherweight at about 80kg, but the sag seems about right and the shock works for me. I hasten to add that I am not particularly fastidious about getting everything dialed in to the nth degree. If it runs and gets me there without extreme physical discomfort or outright injury I'm usually satisfied. Just for the record I once rode round-trip from Ohio to the Yucatan on a 250cc 2-stroke enduro, and to Alaska on a Honda Shadow 1100 cruiser, neither bike admirably suited to the task but sufficient for my limited needs. Those of you who have more nuanced sensibilities with regard to your riding should not take seriously anything I say.

Come to think of it you should not take seriously anything I say on ANY topic.:laugh:
 
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