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Discussion Starter · #1 ·
Hello everyone,

I got picked up a 2011 GSX-R 750 shock to install on my ninja 400, as I see that it is a popular choice for a cheap shock upgrade. I also bought the Norton motorsports brackets so that the shock can mount up properly.

My question is whether these shocks can be rebuilt as they are or will I have to put in one of those aftermarket nitrogen valves (needles) to refill it? I have included a picture of the exact model shock.

I see online that there is a bronze colored GSX-R shock with a Schrader valve visible from the outside of the shock, but on this one there is no nitrogen refill valve visible. Is it hidden somewhere or does it not exist?

I want to install this shock but I was hoping to service it before I do so this way I don't have to take it back off for a while.

Thanks in advance,
17746
 

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Hi Tom,
I'm headed in the same direction. I purchased a GSXR shock on ebay, apparently off of a 2015 and looks just like yours. Like you, not knowing the history of the unit, I wanted to service it before installation. I contacted Super Plush Suspension in San Francisco and they are doing the work for me. It was surprisingly hard to find someone or a shop willing to take it on. I live about an hour north of SF and they were the closest shop that I could find.
 

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I always thought they weren’t serviceable other than changing springs...

Yes, the Suzuki service manual only tells you to drill a hole in it and throw it away, with no information about servicing.

I did talk to someone at Race Tech who said that they could rebuild it, and he thought they had developed a new schrader valve cap they could install on the reservoir. A rebuild would cost around $300 to $350.

So far mine has been working perfectly. I checked all three of the ones that I bought from ebay, and they seemed to have the same nitrogen pressure. I compressed them with the springs removed and the damping screws out all the way, and they all extended at about the same speed.
 

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I have had the GSXR shock on my 400 since 2019. Don‘t know the history of it, seems fine.
If I feel it is no longer working like it should, I will just get another one. In the 50 buck area, it’s a cheap replacement.
 

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Discussion Starter · #6 ·
Thanks to everybody who answered. I had seen a modification available from racetech which allows you to refill- non-refillable shocks. You basically drill a hole in the nitrogen reservoir, put in the needle and you have a Schrader valve.

To be honest I could probably just buy replacements but I like being able to service it. Not only for not having to keep buying them but also because I genuinely like working on cars and bikes, even some harder work like a shock service.

I have been looking for shocks made for the ninja 400 but I can't seem to find anything less than $500. If I could I would sell this shock, which I still haven't put in, and purchased it. The ohlin's shock seems very good, rebuildable, and the look is incredible (as a plus side).The GSX-R750 shock needs a new spring for my weight too- so thats gunna be like another 100$.

@Cornerman- is that new cap taken from the newer shock model (the bronze one with the Schrader valve clearly visible? or is it racetech's own contraption?)
 

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The GSX-R750 shock needs a new spring for my weight too- so thats gunna be like another 100$.

@Cornerman- is that new cap taken from the newer shock model (the bronze one with the Schrader valve clearly visible? or is it racetech's own contraption?)
Search back in the original Shock Swap thread and you will find a chart with stock shocks that have springs that will interchange with the GSXR shock. I am running the spring from a 2012 zx6r on both or our bikes. I paid $30 for the complete shock. You can also play around on RaceTechs site and find stock springs that will work too, this is how I found the my spring.
 

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@Cornerman- is that new cap taken from the newer shock model (the bronze one with the Schrader valve clearly visible? or is it racetech's own contraption?)
I’m not certain. I got the impression that they would adapt one from another shock, but I’m not sure which one.

I can relate to wanting everything to be as perfect as possible, but when you consider the cost of the GSXR shock, a spring, the rebuild, and shipping, I think if I wanted the very best I would opt for an aftermarket shock that was set up for me from the start.

As it is, the shock I’m using, off a 2016 GSXR 1000, is working better than I had hoped. I’m really picky about having good suspension, but after getting the sag and damping dialed, there’s nothing I want to change. With the stock tires I could still feel sharp edged bumps a little, but after I put on a set of Q3+ that is pretty much gone. The bike is still really agile, but now it’s also very stable on its side.
 

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Discussion Starter · #9 ·
I’m not certain. I got the impression that they would adapt one from another shock, but I’m not sure which one.

I can relate to wanting everything to be as perfect as possible, but when you consider the cost of the GSXR shock, a spring, the rebuild, and shipping, I think if I wanted the very best I would opt for an aftermarket shock that was set up for me from the start.

I am considering that route. Maybe I'm just waiting for something a little less premium/ more affordable to come out. Did you buy the Norton battery tray/ shock mount adapters in order to keep the ride height close to stock?
 

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I am considering that route. Maybe I'm just waiting for something a little less premium/ more affordable to come out. Did you buy the Norton battery tray/ shock mount adapters in order to keep the ride height close to stock?

Yes, it worked great. If you haven’t had your ECU flashed yet that would be a good time to do it, since the ECU has to come out to install the Norton shock mount adapter.
 

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Discussion Starter · #11 ·
So it rides basically at stock right? I am going to flash quite soon. I have the full akrapovic system and am ordering the norton velocity stacks. The dyno graph for those two is impressive.
 

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Flipping the shock mount will be enough, the shock mounts flipped when I measured the distance between flipped and normal was like 14.xx mm difference so I said call it 15mm, so if we loose 5mm to the lower shock and raise 15-14mm we should be at a gain of 9-10mm in the rear on the GSX-R shock which puts us at what the Spears raises the stock shock...which it feels spot on to me, I am all for the Spears mount but with loosing 5mm on the GSX-R shock it seemed gaining 10 was better than 5

Here’s a post from the main GSXR shock thread ⬆

@b0Xcrash found the increased rear height (at the shock itself) with the stock upper shock mount flipped to be 9 or 10mm.

After flipping the mount and installing the GSXR shock I measured an increase of 21mm from the rear axle straight up to a point on the rear bodywork with the suspension at full extension.
 

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Discussion Starter · #13 ·
Hello everyone,

Sorry to revive the post but I got in touch with racetech. Their shock bladder caps (that have schraer valves) are not compatible with the GSX-R shock BUT they sell this nitrogen needle that appears to be self-sealing.


LINK: Amazon.com: Race Tech Tsnn01 Nitrogen Needle: Electronics

Does anyone know how this works? Do I need to buy a new bladder, or will the old one self-seal? I haven't seen this type of thing before.

Thanks in advance.
 

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Sorry to revive the post but I got in touch with racetech. Their shock bladder caps (that have schraer valves) are not compatible with the GSX-R shock BUT they sell this nitrogen needle that appears to be self-sealing.
No need to apologize. That sounds like good info.

(y)

Shouldn’t need a new bladder unless yours is leaking. After you charge it the hole seals up similar to the way a basketball does when you fill one with a needle.
 

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The Shock Swap Myth | ComputrackBoston.com explains why you shouldn't bother with cheap shock swaps. If it's something that drops right in and works well as is (like these GSXR shocks for us), it can be a decent upgrade over budget OEM stuff. But if you actually look at the cost and final product of trying to make it perfect, it's not a very good value.

I completely understand being a perfectionist/tinkerer on stuff like this. However, the GSXR shock is designed to be a disposable unit, just a better one than our stock disposable shock. My like-new GSXR shock cost less than that nitrogen needle. As stated above, a rebuild of the shock will cost close to the price of a new aftermarket shock designed specifically for you and your bike. If you're going that far, you might as well just buy the right product to begin with, instead of starting with a cheap hack and ending up paying just as much (or more) to wind up with something that still isn't quite right for the bike.

If you just want to toss a different spring on the GSXR shock you have, this is my post with other shocks' spring rates (look at some of the following posts for more detail on certain models that people have tried).

If you're planning to spend hundreds of dollars trying to make the GSXR shock "perfect", just cut to the chase and start looking at aftermarket. You can also find used aftermarket shocks from partouts, retiring racers, etc. for relatively cheap (even including the cost of a refresh). I snagged a used Penske for my 500 for only $400 (around $1,000 new, from what I've found).
 

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My like-new GSXR shock cost less than that nitrogen needle.
Exactly!

We’re just lucky that we have a decent shock to upgrade to that is so cheap.



I snagged a used Penske for my 500 for only $400 (around $1,000 new, from what I've found).
You lucky dog!

Wish I could find a Penske three way for that price! 😁


I want to install this shock but I was hoping to service it before I do so this way I don't have to take it back off for a while.
I don’t want to make your head hurt, but as the bladder ages it is possible for the nitrogen to begin to leak into the oil without escaping from the shock. You would still see the correct pressure when using the needle, but the damping would begin to get soft.

If mine starts to do that I’ll fling it in the dumpster and install one of the other ones I’ve got.
😃
 

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The Shock Swap Myth | ComputrackBoston.com explains why you shouldn't bother with cheap shock swaps. If it's something that drops right in and works well as is (like these GSXR shocks for us), it can be a decent upgrade over budget OEM stuff. But if you actually look at the cost and final product of trying to make it perfect, it's not a very good value.
+1 I feel into this trap when I first started racing. Bought a 20 yr old GSXR400 with a tired shock so I purchased a late model GSXR600 shock (which pretty much went straight in bar a bit of Dremel work on the knuckle) AND paid to get it serviced. The improvement was marginal. I would have been better off getting the GSXR400 shock serviced as it was fully adjustable or even better, put that money towards a decent aftermarket shock.
 

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Discussion Starter · #18 ·
I definitely would like to buy an Ohlins but since I already paid $50 for the shock and $20 for the norton motorsports mount (that keeps ride height close to stock) I am already invested at this point. The install for me is not just for the performance but the install itself. I am one of the few weirdos that likes the work as much as riding.

I'll probably keep the same spring because it is a 10.5 kg/mm whereas the stock ninja spring is a 10 kg/mm. If I don't like it then I will surely use your thread to find a replacement.

Lastly, the service in my case won't really cost me anything- $15 for the shock oil and another 15$ for the nitrogen needle (the example I included ended up being the wrong model). I'm not going to replace anything else because its not leaky.

I'll service it and let you guys know how it goes in terms of difficulty.
 
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