Replacing a Gen1 rear shock with a Gen2

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Kevin Daly

YES I ran the fatty over!!
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So because I was somewhat unsatisfied with the FJR suspension (too spongy and soft) I wanted to firm it up but I didnt want to spend big money. I had heard that the Gen 2 rear shock was more heavily sprung to accomodate the longer swing arm. Since the shocks are the same configuration the gen 1 and gen 2 shocks are interchagable. So what follows is a brief description of how to swap out the rear shock and a review of the new shocks performance on the Gen 1. Note that the FJR How To page provides instructions to swap the stock with the Ohlins shock. I based this page on their description but cut out the unnecessary stuff.

Below are most of the tools you will need. In addition to what you see you might also want a hammer to tap out the bolts holding the dogbones and shock. Finally it should only take about an hour or two if you take your time.

DSCN1909.jpg


First, you need to get the rear end up high enough to allow the rear shock to slide down and out once loosened. I found 2 pieces of 2x6 ideal as eventually the one under the rear tire can be used to moce the rear tire/suspension to align the dogbones during reinstallation.

DSCN1905.jpg


Next, loosen the spring preload adjuster by first removing the bracket that it is attached to and then remove the preload adjuster from the bracket. There are two allen bolts holding the bracket on each subframe rail. here the bracket is in my had and the preload adjuster is hanging loose above.

DSCN1911.jpg


Next loosen and remove the upper dogbone bolt and allow them to drop down. you might have to tap the bolt through but its should pop loose. After they are free, you can then loosen and remove the lower bolt holding the shock. Finally remove the bolt holding the top of the shock and allow the shock to slide down and out the bottom of the swingarm as shown. Note that the holes on the bottom shock bracket are asymetric. the larger hole belongs on the throttle side (I believe). In either case keep an eye on that, it will matter.

DSCN1913.jpg


Note upon comparison, both shocks are identical in length:

DSCN1918.jpg


To complete the process, simply put the new shock and reverse the process. note that there are specifice torque values for various bolts:

1 Upper shock bolt, 64 Nm (46 ft-lbs).

2 Lower shock bolt, 40 Nm (29 ft-lbs).

3 dogbone bolt, 48 Nm (35 ft-lbs).

Finally reattach the spring preload adjuster to the bracket and then the bracket to the subframe and your done!

PERFORMANCE REVIEW

Anyone who has also done this I would love to hear your comments. The main reason for doing this was to get rid of some of the sloshy sloppy feeling you get when you are leaned over in a corner and hit a bump; commonly described as being in a caddilac. FYI, I weigh about 170 and typically carry my bags with food water and tools everywhere I go. the Gen 2 shock has ~3000mi on it so it is essentially new. I bought it used for $175 from FZ/FJR Mike. Looked like new.

Ok I wipped off 500 miles today to give this new shock a working over. I started out with the dampening at 10 clicks (the range is 0- ~20 clicks). I also set the preload to firm. After about 100 miles the firm was just too much relative to the front forks. I also noted that the rebound dampening was insufficient given the firm setting. on a couple occasions a pothole or bum would bounce me a little out of the saddle. So I first switched to the soft setting and whipped off another 100 miles. It was much more appropriate but was still a little springy so I pulled over and added another 2 clicks and that seemed to more or less dial it in nicely.

Overall I think the rear shock swap was and excellent move; the overall function of the rearend is more appropriate for a more "sporty" ride. I definately think that the weakness of the front end becomes much more apparent once yo are running with a Gen 2 rear shock. I think the front can be dialed in a little more but my bet is that I will need to get some heaver springs to more appropriatly balance front and rear.

So anyone else have any comments or information to contribute?

 
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Kevin, it's a shame you went to all of the trouble you did. The only difference between the Gen1 and Gen2 shocks is the difference in spring rate on the "soft" setting.

The hard/soft lever adjuster is not a preload adjuster. It's a spring selector. The FJR shock has two springs mounted up on it. A stiff short spring and a longer spring. When the lever is set on SOFT, both springs are in use. When the lever is set on HARD, the single longer spring is in use and the short spring is locked out. The longer spring has the same spring rate on both generations of FJR. At least the '05 and '06 models that I have tested at the shop. The shorter spring was a 1400 lb/inch spring on my '05 and on the '06, it tested at 1800 lb/inch.

If you are running on the SOFT setting all of the time, then you would notice a slightly stiffer ride with the Gen2 shock. If you were running on the HARD setting, there would be no change.

 
Is that a brand new Gen 2 shock? If so, where did you get it...how much? My 07 has 19,000 miles on it and I liked the suspension on it until a couple of weeks ago when me and my SO made a trip to Colorado, loaded down, and the shock just didn't work all that well. Had to crank the rear damping down to about #5 to handle the twisties and it rides way too stiff on the slab like that. When you loosen it up for the slab it feels "floaty". Didn't think I'd have to do anything to the shock this soon...

 
Kevin, it's a shame you went to all of the trouble you did. The only difference between the Gen1 and Gen2 shocks is the difference in spring rate on the "soft" setting.
The hard/soft lever adjuster is not a preload adjuster. It's a spring selector. The FJR shock has two springs mounted up on it. A stiff short spring and a longer spring. When the lever is set on SOFT, both springs are in use. When the lever is set on HARD, the single longer spring is in use and the short spring is locked out. The longer spring has the same spring rate on both generations of FJR. At least the '05 and '06 models that I have tested at the shop. The shorter spring was a 1400 lb/inch spring on my '05 and on the '06, it tested at 1800 lb/inch.

If you are running on the SOFT setting all of the time, then you would notice a slightly stiffer ride with the Gen2 shock. If you were running on the HARD setting, there would be no change.
Not a shame at all. First it was not difficult or perticluarly expensive. Second the soft setting is substantially firmer than the Gen 1 hard setting. I have never used anything but the firm setting on the Gen1 and it has always felt undersprung. Both I and my riding buddy Dick noticed a substantial difference. Second the firm setting was rock hard, way too firm for a single rider especially with the front shocks set as is. Now maybe at 29,000 miles I have just exhausted the original shock, but I dont think so.

 
Kevin,

Very Nice Write-up! Thanks for sharing your adventure in which I will be entertaining in the very near future.

 
That's cool!! I didn't think the shocks were the same between generations. I will be searching for one now!!! Thanks
As sportryder points more elegantly than I, there are some differences. In my opinion they do make a positive difference on the suspensions performance.

 
Now maybe at 29,000 miles I have just exhausted the original shock, but I dont think so.
Kevin,

I think you hit the nail on the head there.

Jwilly did the same swap. I gave him my Gen 2 after I put a Penske on the rear. The gen 2 oem had 6500 miles on it IIRC and Williys 03 has many miles on it so I know he felt a difference as well.

Lee, Good to see you posting again.

Love the AKs.

FWIW. before I would buy a gen 2 OEM and do a swap. I'ld pick up a Penske. The difference is HUGE. I know you go with what you can afford, and like I said JWilly's shock was free, so that is a good call on his part.

 
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Now maybe at 29,000 miles I have just exhausted the original shock, but I dont think so.
Yeah, it really is. The stock shocks tend to be good for 15K-25K depending on rider weight and use.

It's certainly an option under the price of an after-market shock that's serviceable and custom to the rider. You're replacing an old, worn-out, and unserviceable stock shock with a new, yet-to-be-worn-out unserviceable stock shock.

 
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Is that a brand new Gen 2 shock? If so, where did you get it...how much? My 07 has 19,000 miles on it and I liked the suspension on it until a couple of weeks ago when me and my SO made a trip to Colorado, loaded down, and the shock just didn't work all that well. Had to crank the rear damping down to about #5 to handle the twisties and it rides way too stiff on the slab like that. When you loosen it up for the slab it feels "floaty". Didn't think I'd have to do anything to the shock this soon...
Dude the slab? whats that :rolleyes: I never ride on the SS. The only reason why I like the SS is that it provides a place for all the cars so they dont have to travel on the state and US routes :) . I imaging that you could have a problem with the Gen 2 shock on your Gen 2 bike. I have never been on a Gen 2 but they do have a longer wheel base and swingarm (as I understand it) thus it exerts greater force on the shock. My understanding is that the Gen 2 shock was sprung heavier to accomodate this but I could be wrong. So I never ride it in a "floaty" state.

PS it wasnt new I bought it used but with only 3000 miles.

 
Now maybe at 29,000 miles I have just exhausted the original shock, but I dont think so.
Kevin,

I think you hit the nail on the head there.

Jwilly did the same swap. I gave him my Gen 2 after I put a Penske on the rear. The gen 2 oem had 6500 miles on it IIRC and Williys 03 has many miles on it so I know he felt a difference as well.

Lee, Good to see you posting again.

Love the AKs.

FWIW. before I would buy a gen 2 OEM and do a swap. I'ld pick up a Penske. The difference is HUGE. I know you go with what you can afford, and like I said JWilly's shock was free, so that is a good call on his part.
Well I was wondering if it was spent but it is kind of a surprise. even new however, I felt that the suspension generally was a bit wimpy relative to a sportbike. I knew jwilly did his swap, was hopin he would pipe in here as well.

For me it really was about the cost; while disposable like Igy points out, this saved several hundred dollars. I got kids and I have to get them through college on a professors salary (ironic that a professor cant affort to educate his kids??).

 
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Kevin, I was thinking last night after I posted my comment that I should have worded it a little bit differently and maybe omitted a comment or two. I shouldn't have said it was a shame that you went to the trouble of swapping it out with a newer OEM shock. Any increase in performance would have been detected due to the mileage difference between one having 29k miles vs one having 3k miles on it. I should also have noted that it's a good thing you took the trouble to post up pictures of your work to share with other owners who may wish to do their own work. Good on you for doing that. I suppose I've gotten to be like some of the techs I've worked with over the past few years - quick to point out things that are incorrect and not so quick to give praise when it is due. You learned something by doing the work and others probably learned something also. Good job! :) You saved a good bit of money and you are happy with the result.

Now maybe at 29,000 miles I have just exhausted the original shock, but I dont think so.
Kevin,

I think you hit the nail on the head there.

Jwilly did the same swap. I gave him my Gen 2 after I put a Penske on the rear. The gen 2 oem had 6500 miles on it IIRC and Williys 03 has many miles on it so I know he felt a difference as well.

Lee, Good to see you posting again.

Love the AKs.

FWIW. before I would buy a gen 2 OEM and do a swap. I'ld pick up a Penske. The difference is HUGE. I know you go with what you can afford, and like I said JWilly's shock was free, so that is a good call on his part.
Well I was wondering if it was spent but it is kind of a surprise. even new however, I felt that the suspension generally was a bit wimpy relative to a sportbike. I knew jwilly did his swap, was hopin he would pipe in here as well.

For me it really was about the cost; while disposable like Igy points out, this saved several hundred dollars. I got kids and I have to get them through college on a professors salary (ironic that a professor cant affort to educate his kids??).
 
Kevin, I was thinking last night after I posted my comment that I should have worded it a little bit differently and maybe omitted a comment or two. I shouldn't have said it was a shame that you went to the trouble of swapping it out with a newer OEM shock. Any increase in performance would have been detected due to the mileage difference between one having 29k miles vs one having 3k miles on it. I should also have noted that it's a good thing you took the trouble to post up pictures of your work to share with other owners who may wish to do their own work. Good on you for doing that. I suppose I've gotten to be like some of the techs I've worked with over the past few years - quick to point out things that are incorrect and not so quick to give praise when it is due. You learned something by doing the work and others probably learned something also. Good job! :) You saved a good bit of money and you are happy with the result.
Lee, dont worry bout my feelings, I appreciate critical comments. Now I know more about the shock than I did.

Since I have your ear, tell me, I understand in the literal sense that the "selector is not changing the preload on the main spring but is selecting an internal spring/s. Functionally, what's the difference? Are you not in both cases changing the total spring force of the shock?

-k

 
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Good job on the swap and sharing the pics. As Iggy mentioned, at 29k, most stockers will be noticeable worn. And you're quite right about the gen I not being all that stiff to begin with. It was common for riders to scrape hard parts on the 'soft' setting.

Just so you know, way back in the day, spacer shims were made up to bump the pre-load on the spring up a bit. Three sizes were done, 1/8", 3/16" and 1/4" IIRC. You would tuck this in below the spring, (required a spring compressor to disassemble and reassemble the shock), and it did help. This was primarily for the '03 shocks which were even weaker sprung than the '04/05 Gen I shocks, but it worked on any shock if the rider needed some help and was short on coin. These are probably still floating around in rider's garages.

Something I'd also like to mention - Rebuildable aftermarket shocks are a huge improvement if you can afford it down the road, BUT, they still need to be rebuilt every 20-40k depending on the rider and how they ride, (one up, two up, sporty, touring, etc.). Cost me about what you paid for the Gen II shock to have my Wilbers rebuilt and re-sprung. Most would not need a new spring, ($100), on other shocks, but mine was just too soft to begin with. Expect to pay about $100 to get rebuilds done, give or take.

 
I knew jwilly did his swap, was hopin he would pipe in here as well.
Sorry I just saw the this thread. I replaced my stock rear with 38K on it for the one I got from Fencer. There was a noticeable difference in the ride being more firm. Like Lee mentioned I think it's kind of a temporary patch because the stock shock has a limited life to it. With so many people on the forum replacing their stock unit with aftermarket it can make for an inexpensive replacement for those who can't afford an aftermarket shock.

I've only put a few thousand miles on mine so after EOM I will probably have more feedback.

Good pics and description Kevin!! I was able to do mine with Corona w/lime. Just so you know.

JW

 
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I knew jwilly did his swap, was hopin he would pipe in here as well.
Sorry I just saw the this thread. I replaced my stock rear with 38K on it for the one I got from Fencer. There was a noticeable difference in the ride being more firm. Like Lee mentioned I think it's kind of a temporary patch because the stock shock has a limited life to it. With so many people on the forum replacing their stock unit with aftermarket it can make for an inexpensive replacement for those who can't afford an aftermarket shock.

I've only put a few thousand miles on mine so after EOM I will probably have more feedback.

Good pics and description Kevin!! I was able to do mine with Corona w/lime. Just so you know.

JW
haha! :lol: cheap Mexican beer! :rolleyes: I was wondering if anyone would notice those sitting promenently in the background :rolleyes:

Thanks for the comments. It is a shame that the stock shocks are SO damn disposable and only last for such a small number of miles. I suppose we are talking about loss of function that most people in a car wouln't notice.

 
JWilly's old rear shock was blown. You could have bolted a steel rod in its place and improved the handling on his bike!

I'm just now starting to feel some substantial performance degradation on the OEM 07 rear shock. So that's 50,000 miles of excellent performance for a bike that we all know has been babied through every corner. :rolleyes:

In previous threads of days gone by, I've mentioned several times about the spring quality possibly being better on the Gen-II than the Gen-I. IMO, improved "grading" or quality control from the spring manufacturer definitely improves the predictability and overall performance of the Gen-II suspension pieces over Gen-I.

So I say "good for ya". You will, IMO, get a lot of bang for the bucks you spent on the Gen-II.

The downside is you have now raised the "going price" for all those leftover Gen-II shocks!!!

:(

 
Kevin,

When you actually have a preload adjuster, there are multiple settings, not just 2. If the shock body has threads on it, there could be an infinite number of different settings. However, preload doesn't change the spring rate so with the HARD/SOFT lever, you are actually selecting two separate spring rates. It's kind of a neat design and pretty ingenius how they did it but with their spring rate selections, they still missed the target. The longer spring on both my '05 and a customer's '06 that we have tested both were very close to 670 lb/inch springs. The Gen2 swingarm is a bit longer but it also has a different "L" shaped relay arm so they played with different geometry at the same time they lengthened the swingarm. On the '05, the soft setting was basically unusable it was so soft and the hard setting was still soft for two-up riding or one-up with a guy weighing much over 200 lbs and wishing to ride in a pretty sporting way. I believe the change they made to the shock springs was to firm up the rear suspension to make the SOFT setting a bit more usable. However, the hard setting was still too soft for someone over 200 carrying a passenger. This is why I feel they still missed the target. For most of the FJR owners I've worked with, the 850 lb spring on a Penske has been used most often. It gives a pretty decent ride one up or two up with gear with only a minor preload adjustment needing to be made for two up riding. I've never cared much for having to make a preload adjustment for every different riding scenario. This is why I liked the 850 lb spring on the Penske with the FJR and I've tested several different springs on it. If you wanted a soft cushy ride, you could back the preload adjuster off by 1/2 to 1 turn from the standard setting that I would prep the shock with. For 2-up riding with loaded luggage (side-bags only) I would add 1 to 1.5 turns on the preload collar. These changes only take a couple of seconds to complete. It's not as easy as a simple HARD/SOFT lever though. The 670 lb spring is pretty soft but Yamaha and Soqi (the shock manufacturer) use a lot of preload on the spring for their setup. We don't use much preload on the 800 to 900 lb springs that get put on the FJR Penske shocks.

Kevin, I was thinking last night after I posted my comment that I should have worded it a little bit differently and maybe omitted a comment or two. I shouldn't have said it was a shame that you went to the trouble of swapping it out with a newer OEM shock. Any increase in performance would have been detected due to the mileage difference between one having 29k miles vs one having 3k miles on it. I should also have noted that it's a good thing you took the trouble to post up pictures of your work to share with other owners who may wish to do their own work. Good on you for doing that. I suppose I've gotten to be like some of the techs I've worked with over the past few years - quick to point out things that are incorrect and not so quick to give praise when it is due. You learned something by doing the work and others probably learned something also. Good job! :) You saved a good bit of money and you are happy with the result.
Lee, dont worry bout my feelings, I appreciate critical comments. Now I know more about the shock than I did.

Since I have your ear, tell me, I understand in the literal sense that the "selector is not changing the preload on the main spring but is selecting an internal spring/s. Functionally, what's the difference? Are you not in both cases changing the total spring force of the shock?

-k
 
Kevin,
When you actually have a preload adjuster, there are multiple settings, not just 2. If the shock body has threads on it, there could be an infinite number of different settings. However, preload doesn't change the spring rate so with the HARD/SOFT lever, you are actually selecting two separate spring rates. It's kind of a neat design and pretty ingenius how they did it but with their spring rate selections, they still missed the target. The longer spring on both my '05 and a customer's '06 that we have tested both were very close to 670 lb/inch springs. The Gen2 swingarm is a bit longer but it also has a different "L" shaped relay arm so they played with different geometry at the same time they lengthened the swingarm. On the '05, the soft setting was basically unusable it was so soft and the hard setting was still soft for two-up riding or one-up with a guy weighing much over 200 lbs and wishing to ride in a pretty sporting way. I believe the change they made to the shock springs was to firm up the rear suspension to make the SOFT setting a bit more usable. However, the hard setting was still too soft for someone over 200 carrying a passenger. This is why I feel they still missed the target. For most of the FJR owners I've worked with, the 850 lb spring on a Penske has been used most often. It gives a pretty decent ride one up or two up with gear with only a minor preload adjustment needing to be made for two up riding. I've never cared much for having to make a preload adjustment for every different riding scenario. This is why I liked the 850 lb spring on the Penske with the FJR and I've tested several different springs on it. If you wanted a soft cushy ride, you could back the preload adjuster off by 1/2 to 1 turn from the standard setting that I would prep the shock with. For 2-up riding with loaded luggage (side-bags only) I would add 1 to 1.5 turns on the preload collar. These changes only take a couple of seconds to complete. It's not as easy as a simple HARD/SOFT lever though. The 670 lb spring is pretty soft but Yamaha and Soqi (the shock manufacturer) use a lot of preload on the spring for their setup. We don't use much preload on the 800 to 900 lb springs that get put on the FJR Penske shocks.
Right so, what you are saying is that the advantage of the aftermarket is more flexibility/variability in the total preload options. Thats a valid point but I guess what I dont understand is the difference between preload and spring rate. I mean preload is how much you compress the spring but is spring rate how much force it takes to deform the spring to some criterion?

I am also curious about this L-shaped arm you mention; are you refering to the pivot triangle that the shock connects to? How did they change it? just a curiosity.

I think too you have very elegantly pointed out the tradeoff between the stock and aftermarket shocks. If I had my druthers and the cash, I would certianly take a nice aftermarket shock (Seriously, somebody send me one and I'll write up a review with some pics and stuff :rolleyes: ).

 

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