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Discussion Starter · #1 ·
Has anyone come up with a cheap way to improve the rear suspension?
Maybe a shock swap from another bike, or stiffer spring swap?

It would be great if a used $100 dollar shock from another bike like an R6 or SV650 would fit.

Anyone have any idea's, or tried anything yet? Is the spring removable on the R3 shock?
 

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buy the Ohlins or YSS from Thailand(?). Anything else is just wasting money and time.

BTW http://www.r3-forums.com/forum/562-suspension/56553-compatible-shocks.html. That's the thread for this. And no, no answers yet.

If you want to search for possible candidates, this might help.
http://www.bikehps.com/ohlins/ohlins_application_list.pdf

Suspension DESERVES money to be spent on it. People spend hundreds on useless cosmetics and noise, yet ignore the most important part of motorcycle dynamics.

I'm not saying the shock doesn't come apart - it should. In which case have a tuner put a Racetech GV and shim stack in there. And replace the spring with the correct rate. A 'sportbike' shock at less than $100 looks attractive but if you don't spend another $150-250 to revalve/respring it you're just wasting money.
 

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Yes you can resprung your rear shock but that's only half the battle since the oem one doesn't have any damping adjustability. There are tools you will need to respring your shock, that may cost hundreds of dollars. There are a few cheaper solutions as well, and even a few home made contraptions. If you go to the weraclsssifieds there is a guy that was selling one. I am sure with that picture and some square tubing and meta plate you can have a welder fabricate the same spring compressor for less than $100 in parts and labor.
 

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Discussion Starter · #4 ·
Thanks for the info. I totally agree with you about how people spend all kinds of money on useless things that don't add any performance. So far the only things I've spent money on are some s20 evo tires and a ss brake line in the front.

For me, at 240 lbs I'm not looking at fine tuning a shock that is ok and does the job already, I'm looking at finding something with a stiffer spring rate that will work better for my weight. If I was under 160 lbs I'm sure the shock would be just fine for me. That's why I was looking for options. It really isn't all that bad as is, but I know it probably could be better. Because of my weight, I always re spring immediately when I get a new dirtbike. For the R3, If I could get away with some preload adjustable fork caps and a stiffer rear spring I think that would be all I need to be happy. Right now it rides like a big marshmellow with my weight.
 

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Has anyone come up with a cheap way to improve the rear suspension?
Maybe a shock swap from another bike, or stiffer spring swap?

It would be great if a used $100 dollar shock from another bike like an R6 or SV650 would fit.

Anyone have any idea's, or tried anything yet? Is the spring removable on the R3 shock?

I run lighter tyres (S20) remove sprocket ring, chainguard, lighter Non oring chain, (and alloy rear sprocket coming.)
6mm lower forks in the clamps and spring on 6/7.
Running a longer wheelbase as the fwd weight bias offsets the leverage ratio, my bike is planted yet turns in perfectly.
All these things take the workload off the shock.


Yet to have any rear shock problems and I push pretty hard, done about 50 track, tuning and race days in the past 4 years on MC41 and Ninja and the R3 feels like a dream to me.


I wil be racing on the std shock as dems da rulz.
 

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If you get preload adjusters get th spears racing ones. There are cheaper ones I have bought before from eBay and they were ok but boring silver. The spears ones look to be well made for only slightly more. Just be sure t seals properly. Mine was leaking air at one point because of a bad oring.
 

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buy the Ohlins or YSS from Thailand(?). Anything else is just wasting money and time.

BTW http://www.r3-forums.com/forum/562-suspension/56553-compatible-shocks.html. That's the thread for this. And no, no answers yet.

If you want to search for possible candidates, this might help.
http://www.bikehps.com/ohlins/ohlins_application_list.pdf

Suspension DESERVES money to be spent on it. People spend hundreds on useless cosmetics and noise, yet ignore the most important part of motorcycle dynamics.

I'm not saying the shock doesn't come apart - it should. In which case have a tuner put a Racetech GV and shim stack in there. And replace the spring with the correct rate. A 'sportbike' shock at less than $100 looks attractive but if you don't spend another $150-250 to revalve/respring it you're just wasting money.
I agree with Matt. A lot of people will say the shock is ok and that's fine. If you do get to ride a bike with an actual tunable suspension you will definitely know the difference. Once I got a bike with an actual tunable suspension I never wanted to go back. If you ask why my R3 hasn't been upgraded yet it's because I know I would only own the bike for a few months before having to sell again. Otherwise my forks and shock would have been the first to be upgraded.

I didn't think an upgraded suspension was worth the money when I still owned my N650 but once I took the leap I definitely then knew what everyone who raved about suspension tuning meant. My first real "upgrade" to my suspension was intiminators. Going from non adjustable forks to those were a difference maker. Going from that to a zx6r fork upgrade was definitely a huge improvement. I also ended up sticking an ohlins shock on that bike. It was a KA906 that adjusted the reb/comp with one adjuster. That was a big upgrade imo. After getting an 09 zx6r with pre/comp/reb adjuster up front and pre/hi/low comp/ reb on the rear, I definitely no longer want to own a bike with just preload adjustments. I can talk about how great it is all day but in the end you really have to try it to appreciate what a great suspension set up can do for your bike and how much it improves ride quality, weather you track or not, push it or cruise.
 

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I wonder if the yss shock has a stiffer spring rate than stock shock?
highly doubtful. YSS generally comes with just one spring. An Eibach can fix that right up. Unless the rate as delivered and desired is hugely different the internals can probably cope with the extra force.
 

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lowering can be done via:

changing actual length of shock piston rod
changing the perceived length of piston rod with a spacer (but will lose travel)
dog-bones

most aftermarket shocks lend themselves to easy part swaps so the first 2 options are increasingly available.

No, the above shock by itself and in factory condition won't lower your bike but there's a good chance you can have a YSS builder swap out the shaft.
 

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lowering can be done via:

changing actual length of shock piston rod
changing the perceived length of piston rod with a spacer (but will lose travel)
dog-bones

most aftermarket shocks lend themselves to easy part swaps so the first 2 options are increasingly available.

No, the above shock by itself and in factory condition won't lower your bike but there's a good chance you can have a YSS builder swap out the shaft.
Thanks - finally someone who can educate me on suspensions! So what's your take on the T-Rex Lowering Links? My impression is that they don't look very safe. Is there *any* way to make adjustable rear lowering links for the R3?

What do you think of the Honda Grom rear shock swap that others have been talking about (and some have done)?

Could you (don't faint here) cut one of the windings on the stock spring? Or buy a shorter spring with the stock shock? I've seen the Krooz option of a shorter shock with the stock spring - but wouldn't that make it too bouncy?

Sorry for all the questions, just trying to understand the options.
 

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short cuts will almost always guarantee lousy results. Rather than thread jack, I posted in the "shorten" thread.
 

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I posted this response to another similar thread explaining the unique suspension on the R3:

"I wish I would have seen this post awhile ago, I can offer some input here. There is only 1 OEM shock on the market (that I've found) that comes close to working with the R3, and here's the reason why...

Most bikes use a progressive link type rear suspension (there are dog bone links under the shock), and therefor, use a similarly soft shock spring (the OEM spring on an R6 shock is about 600 lb/in and works well for a racer around 225lbs or a street guy around 260 lbs, I ran a 550 lb spring on my R6 and I weigh 160). The progressive link allows the suspension to feel softer at the beginning of the stroke, but it gets stiffer and stiffer the more you compress it, so it can be soft at the start, and still support the rider at higher speeds, while cornering, and while braking by changing the leverage through the stroke. The R3 is one of only a few bikes that doesn't have a progressive link type rear suspension (the Ninja 650R is another one). This means the rear suspension is linear. A soft shock spring will feel plush and lower speeds, but as you go faster and compress the shock more, smaller bumps and throttle changes cause a large change in the rear and you blow through the stroke. A stiffer spring will feel rock hard when riding slow and hitting bumps, but when under heavier load while cornering, will sink into the middle of the stroke and work properly. But, the linear, linkless suspension has a much different mechanical advantage. The "super soft" stock spring on the R3 is around 700 lb, which would be rock hard on a lot of other bikes. I run a 1200 lb spring on my Penske shock. It feels very hard when sitting still, but works amazing when going fast, and the valving in the Penske must be very stiff to match the different mechanical advantage and the heavier spring.

This difference is why you can take a shock from a GSXR (about 317mm eye to eye length and I think the spring is around 500lb) and put it on a Ninja 250 (OEM length about 315mm) and have it work great, as they both use similar mechanical link systems and the small length change benefits the Ninja, but if you try to put a 317mm GSXR shock on an R3 you run into tons of problems. The R3's OEM shock is 275mm eye to eye, so it's very short, and the R3's stock spring is (estimate) 700 lb, so the GSXR's 500 lb spring is going to be even softer. The R6 is another one to consider, as the length is shorter, 291mm, but it has a stock spring of about 600lb, so again, it will be even softer than the stock R3 spring.

For those of you not as familiar with suspension valving, the valving inside the shock must be closely matched to the load on the shock (the rider weight pushing against the spring (at least within the adjustment range). This means you can't just take an R6 shock and change the spring out for a way stiffer one, or the valving will be too soft and be ineffective at damping the higher forces generated by the rider and the spring with the mechanical advantage of the R3s suspension setup.

By now, it's pretty common knowledge amongst racers that the R3 benefits from raising the rear by lengthening the shock, which increases the angle from the chain to the swingarm, and increases ground clearance. So a longer shock is a good thing, but there's a limit. For example, I run my shock at 287mm, 12mm longer than the stock shock.

So, what is the OEM shock that works for the R3? Well, looking back at that other bike with a linkless suspension, the Ninja 650. The 650 OEM shock is also very short, at 290mm, which is a good length to raise the R3 slightly. And the Ninja 650 is a heavier bike with a more powerful motor than the R3, so it would make sense that it may have a stiffer spring and valving. The Ninja 650's oem shock has a 970 lb spring, and valving to match, which again, is decent, especially for an upgrade for street riders. The downside to the 650 shock, is that it only has basic preload adjustment, like the R3, so it may be an upgrade, but it's a pretty limited upgrade, and it will only work well for 1 particular weight, since even though it has preload adjustment, ideally, the preload must be matched to the rebound damping. Still, it's a cheap upgrade. I have a 650 shock showing up in a day or 2 so I can put together a cheap mounting kit to use it with the R3. I think it might be a nice little budget street upgrade.

But, the bigger news, is that I still have wanted to find a budget racer solution, that's fully adjustable. So watch for a full post on this in my forum, but I finally finished and installed the first R6 shock conversion in a local rider's bike this past weekend. I took an OEM R6 shock, machined the mount to shorten the length from 291 to 287, to match what I use on my bike. Then machined some spacers and put together a mounting kit to mount it on the R3. I then shipped the shock off to Traxxion Dynamics to tear it down and rebuild it with new valving to match a stiffer spring (in this case, the rider weighs 160, like me, so it's built with a 1200 lb spring). The valving is also centered in the adjustment range, so it has plenty of adjustment for different rider weights and even a few different spring rates.

To mount the shock on the R3 requires a small modification to the bike. I will do a complete How to guide very soon, but basically, a small bracket in the subframe and part of the front of the battery box must be trimmed out to make room for the piggyback canister on the R6 shock.

The install was actually quite painless, and the results so far are excellent. The bike will be on track testing it out and working with my local suspension guy this coming weekend, so I'll have more results then, and will be offering this for sale in the next week or 2. A few extra machined parts were needed, so the cost is a little higher than the $360+ OEM R6 shock core that I initially was hoping for, but not by much."


That all being said, as torrid_pace noted, I have release my R3 Race Spec. shock, which is rebuilt from an R6 shock. And I'm also making a spacer kit to fit up a Ninja 650 shock to the R3, which will be available soon. And, in 3 weeks at Buttonwillow, I'm going to run the piss out of my Penske, my R3 Race Spec. shock, and a Ninja 650 shock back to back to back at a track day and then I'll be able to give some good apples to apples feedback on all three and we'll see what happens to my lap times.

Cheers
 
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