Looking for suspension advice for first track bike

[Yamahawk]

Ok, I thought about that, but was hoping the 06 GSXR1000 spring would be the same diameter as the 06 GSXR600 spring was. The 03 GSXR600 spring had a larger diameter lower ring also, but it would not thread on like the original GSXR600 lower ring, and then if you wanted a lock ring, there would be three rings, instead of two... I really don't want a larger diameter spring if I can help it, as the clearance in my 86 EX250 swing arm is going to be tight already. What year was the GSXR1000 donor shock that you got the spring from? And, thanks for the reply, brother!
Charlie

[daverdfw]

Originally Posted by Yamahawk

Ok, I thought about that, but was hoping the 06 GSXR1000 spring would be the same diameter as the 06 GSXR600 spring was. The 03 GSXR600 spring had a larger diameter lower ring also, but it would not thread on like the original GSXR600 lower ring, and then if you wanted a lock ring, there would be three rings, instead of two... I really don't want a larger diameter spring if I can help it, as the clearance in my 86 EX250 swing arm is going to be tight already. What year was the GSXR1000 donor shock that you got the spring from? And, thanks for the reply, brother!
Charlie

it was a 05-06 GSXR1000 shock

[Yamahawk]

Originally Posted by daverdfw

it was a 05-06 GSXR1000 shock

Ok, I have been on RaceTech's site and looking at the available shock springs, I see why there is a size difference. The 06-09 GSXR600-750 rear shock is a 40mm body, while the rest of the GSXR's (1000, early 600-750's) are all 46mm bodies. The pre-2000 GSXR shocks are 40mm, but the springs are markedly longer, so they are out... I am thinking that the best solution is to get a RaceTech new/used spring with the 8.5-8.9kg rating. That would give a spring that will be the right range for our Ninja's and rider weight 180... hehe if I gain 2-3 horsepower of the winter. (lose 10-15 lb.)
The number of the spring, if you are interested, is SRSP-5818085 or 089 fro the last three digits.
I will do some searching and see if I can come up with one reasonably priced.
Charlie

[pattonme]

why all the fascination with this GSXR spring or that? Buy an Eibach at the correct ID and correct rate. They are like $60. Otherwise shouldn't there be a thread that documents all the relevant shock springs, their dimensions and rates, and suitable rider weight range so folks can reference? Or did I miss it?

I'll absolutely second/third/forth those say to send the GSXR/R6 shock off to get serviced, lengthened (?) and revalved. It's madness to use the wrong item to "save" a couple dollars. If you're going to do it, spend the 350 and do it right.

Some of these 'light' bikes need 5-10mm longer shocks for best chassis and weight balance. I don't know if the 250/300 fall into this category or not.

First, fix the obviously wrong stuff - fork springs and a thick enough oil to compensate probably around 35-40cSt@40. If the frontend now won't track and is skittish when hitting bumps, drill some relief holes in the damper rod.

[Somchai]

Originally Posted by pattonme

why all the fascination with this GSXR spring or that? Buy an Eibach at the correct ID and correct rate. They are like $60. Otherwise shouldn't there be a thread that documents all the relevant shock springs, their dimensions and rates, and suitable rider weight range so folks can reference? Or did I miss it?

I'll absolutely second/third/forth those say to send the GSXR/R6 shock off to get serviced, lengthened (?) and revalved. It's madness to use the wrong item to "save" a couple dollars. If you're going to do it, spend the 350 and do it right.

Some of these 'light' bikes need 5-10mm longer shocks for best chassis and weight balance. I don't know if the 250/300 fall into this category or not.

First, fix the obviously wrong stuff - fork springs and a thick enough oil to compensate probably around 35-40cSt@40. If the frontend now won't track and is skittish when hitting bumps, drill some relief holes in the damper rod.

[cbinker]

Originally Posted by pattonme

why all the fascination with this GSXR spring or that? Buy an Eibach at the correct ID and correct rate. They are like $60. Otherwise shouldn't there be a thread that documents all the relevant shock springs, their dimensions and rates, and suitable rider weight range so folks can reference? Or did I miss it?

Not sure what you are pointing out here? are you referring to replacing the stock spring? if thats the case then you haven't seen the stock shock.

Originally Posted by pattonme

First, fix the obviously wrong stuff - fork springs and a thick enough oil to compensate probably around 35-40cSt@40. If the frontend now won't track and is skittish when hitting bumps, drill some relief holes in the damper rod.

In all honesty, I would suggest stiffening the rear first then finding a good front set up. You don't steer from the rear on these bikes, you ride the front end. The problem i have experienced with stiffer fork springs is that i am having a tougher time having feel in the front of the bike.

[pattonme]

I was just commenting on the several instances I read of "I put an '03 spring on an '06 shock or 08 spring on '03 shock or this OEM spring here or that one" and permutations of above as opposed to buying the right diameter spring and the correct rate. No doubt riders of a certain weight can utilize one of these OEM springs but lacking a chart that describes their characteristics, seems a bit of random what-if pairings being attempted.

So if you ride the frontend, why wouldn't you just ride around the shock's limitations (OE or GSXR etc.) while making sure the front is as sorted as best you can and trying not to unduly influence those settings because of the bouncy rear?

Fixing the forks comment was aimed at the original poster who is heavy. I can't speak to your preferences for 'mush' vs 'stiff' but I see you own a S1000RR so I expect you have some appreciation for firm yet supple (or not) forks are supposed to feel like.

[ROADandTRACK]

They are talking about using those springs on that year GSXR shock.

But, I agree. If you can't measure the spring rate yourself I wouldn't use a spring from some OEM shock.

Also, just putting on the spring, even if you get a rate that works for you, the shock is too short and putting on dogbones to compensate is not a very good way to gain decent suspension. The leverage ratio wrong. It is just a band-aid and it won't handle anywhere near as good as it could. But, the philosophy here is just get'er done CHEAP.

[SLOWn60]

Known as: "Penny wise; pound foolish!"

[Somchai]

Originally Posted by ROADandTRACK

They are talking about using those springs on that year GSXR shock.

But, I agree. If you can't measure the spring rate yourself I wouldn't use a spring from some OEM shock.

Also, just putting on the spring, even if you get a rate that works for you, the shock is too short and putting on dogbones to compensate is not a very good way to gain decent suspension. The leverage ratio wrong. It is just a band-aid and it won't handle anywhere near as good as it could. But, the philosophy here is just get'er done CHEAP.

[daverdfw]

I am definitely going to get the rear shock swapped out after my first season of track days. Probably will just fork out the $ for a Penske or Ohlins or the frankenstock from ROADandTRACK. I am hoping the GSXR with the other spring will at least be better than OEM for my first few track days. I also am going to do springs and heavier oil in the fronts

[Yamahawk]

I am going to fab up an adaptor for the lower clevis, and that should give enough height to the 06 GSXR600 shock to raise it a little more than stock. For racing, that will allow the bike to turn in quicker, and i figure that about 8-10mm higher than the stock shock will be a plus. I think Matt's suggestion of ordering an Eibach spring for it will be on the list, also. They seem affordable at around $60, and with the stock GSXR valving, it may be ok, at least it will be better than the EX250 stocker, which isn't good for much...
My plans are to make a bolt on adaptor that utilizes the stock mounting, and weld up some plate that will allow me to custom fit it to the lower rocker, alleviating any 'grinding' of the inner clevis, or the rocker. Also, it will allow me to keep the stock dog bones to give the suspension the same ratio/travel as it should have. Spring approaches fast, and before you know it, it will be racing season again!

[Yamahawk]

Originally Posted by ROADandTRACK

They are talking about using those springs on that year GSXR shock.

But, I agree. If you can't measure the spring rate yourself I wouldn't use a spring from some OEM shock.

Also, just putting on the spring, even if you get a rate that works for you, the shock is too short and putting on dogbones to compensate is not a very good way to gain decent suspension. The leverage ratio wrong. It is just a band-aid and it won't handle anywhere near as good as it could. But, the philosophy here is just get'er done CHEAP.

There is a chart, I believe from InvisiBill, that shows all the spring rates from the different years and models of GSXR1000/750/600 shocks, and that is where I was referring to for my previous posts. I agree, that randomly selecting an unknown spring from a bike and making it fit is a bad idea. After careful research through RaceTech's spring calculator, and looking at the differences in shock diameter, I don't think swapping a 46mm shock body's spring (03 GSXR1000) onto a 40mm shock body (06 GSXR600) is a good idea for the EX250. The clearance in the swing arm area is already tight, and adding the larger diameter spring from a 46mm shock, would just add to that problem. So, I am going to order one that will be a proper fit and spring rate for the GSXR600 shock, and work with it. Also, with the cartridge conversion for the front forks, and the 17" wheels off the EX500 2nd gen, it should handle pretty well!

[Somchai]

Charlie for adjustability of the height maybe the attached picture could give you an idea?

[ROADandTRACK]

We measure springs all the time that are supposed to be a certain rate from a certain bike and they are not even close to that. So if you can't measure it yourself what is the point. Just buy a new spring, they aren't that much $$$.

Using dogbones to correct the ride height does not work correctly.

[Yamahawk]

Originally Posted by ROADandTRACK

We measure springs all the time that are supposed to be a certain rate from a certain bike and they are not even close to that. So if you can't measure it yourself what is the point. Just buy a new spring, they aren't that much $$$.

Using dogbones to correct the ride height does not work correctly.

I agree. Lengthening the shock is the way to go for proper suspension setup for the track. If it was just something I would ride around as a commuter, I would think about the adjustable dogbones like Somchai posted a picture of. I appreciate that too, Somchai! Thanks!!

[Somchai]

@ROADandTRACK and @Yamahawk
My advice about the adjustable dog bone was just for an easy and quick solution.
Some time ago I'd already post this:
https://www.ninjette.org/forums/show...5&postcount=62
From there: "And let me say one word about the GSX-R shock, when one reads in the German gixxer forums one can read that around 50% of all 600/750 Gixxer-rider (not the 1000 cc) change the spring of the rear shock to a softer one and this also means nearly no rider is happy with the rear spring, but some guys just take it like it is."
https://www.ninjette.org/forums/show...8&postcount=64
From there: "But please remember what you are doing:
- with a shorter shock (which from the low sales price could be understood at the end of its life-cycle already) made for a complete different bike (and not only from progression) you are changing the progression of the Ninja's suspension in one way
- just to then use different dog bones to change the progression more backwards in the opposite way
and this only to talk about height and not about the internal components of the gixxer-shock."

But what does the lonely caller in the desert mean against all those experienced experts?

[ROADandTRACK]

The shock is only one of the issues. The other is the linkage which is way off and you cannot fix that problem with the dogbones.

[Yamahawk]

Originally Posted by ROADandTRACK

The shock is only one of the issues. The other is the linkage which is way off and you cannot fix that problem with the dogbones.

I am not sure I understand about the linkage being way off - does this mean that the stock EX250 linkage is way off? Please explain about this, as I want to learn and understand what is correct on the rear suspension, and what isn't.
I plan to use a low mileage 06 GSXR600 shock that'll be lengthened to compensate for it's initial length being less than the stock EX250 shock. It will have an Eibach spring for the correct weight of the bike, and my weight. The stock rocker, dogbones and swing-arm will be kept. If it needs to be re-valved for the difference in weight or geometry, I may eventually do that. I have to believe that it would be a superior shock to the stock, nonadjustable shock that comes on the Ninja, so it should be a good improvement.
Also, @Somcai I have read your postings about that before, and agree. I am still learning, and do not have all the answers, so I ask questions and read as much as I can.
I had Jamie Daugherty set up a CBR600F3 rear shock, converted to clevis and resprung and re-valved for my VTR250 Interceptor that I currently race. It does really well, and I may add cartridges to the front forks for it, also as I transplanted 37mm CBR600F1 forks when I built it. Anyway, enlighten me, on this linkage dilemma, hehe.

[pattonme]

shocks are valved not just for spring but also wheel rate (aka linkage ratio). I'd say get a copy of Tony Foale's chassis dynamics software and go measure the various parts. But maybe R&T or Spears etc. have already done that and can share.

Say the EX shock moves 1/2" for every 1" of wheel and the GSXR moves 2/3". The valving and flow characteristics of the pistons are different.

this might be useful reading
http://www.ex-500.com/index.php?topic=19865.20;wap2

[pattonme]

shocks are valved not just for spring but also wheel rate (aka linkage ratio). I'd say get a copy of Tony Foale's chassis dynamics software and go measure the various parts. But maybe R&T or Spears etc. have already done that and can share.

Say the EX shock moves 1/2" for every 1" of wheel and the GSXR moves 2/3". The valving and flow characteristics of the pistons are different.

this might be useful reading

http://www.promecha.com.au/leverage_linkages.htm

[Somchai]

From Matt's link, very interesting:
"Yes, the front leverage ratio. The forks are not vertical, so the fork springs have to compress about 1.1mm for every 1mm of vertical axle movement. That means the effective spring-rate at the front axle is about 20% greater than the sum of the fork spring rates."

[Yamahawk]

Originally Posted by pattonme

shocks are valved not just for spring but also wheel rate (aka linkage ratio). I'd say get a copy of Tony Foale's chassis dynamics software and go measure the various parts. But maybe R&T or Spears etc. have already done that and can share.

Say the EX shock moves 1/2" for every 1" of wheel and the GSXR moves 2/3". The valving and flow characteristics of the pistons are different.

this might be useful reading

http://www.promecha.com.au/leverage_linkages.htm

Nice article, Matt! Thanks, I understand a bit more of why the GSXR600 shock might not be optimal for the EX250, as the linkage ratios aren't the same. I am not sure if it would be unusable, but it would most likely have to have valving changes, and possibly travel mods for total shock movement. I am wondering if the valving is progressive in the shock also, or does it just have static changes in the compression and rebound damping, and we set it to act/react well with the bike's suspension travel and weight?

[pattonme]

I don't think anybody is suggesting it's unrideable or unuseable as-is, just not optimal but more importantly, it's untested ground. Goodness knows there are a ton of SV650's running around with GSXR shocks from ebay just slapped in there without so much as a spring change.

[tgold]

Originally Posted by Yamahawk

I am not sure I understand about the linkage being way off - does this mean that the stock EX250 linkage is way off? Please explain about this, as I want to learn and understand what is correct on the rear suspension, and what isn't.
I plan to use a low mileage 06 GSXR600 shock that'll be lengthened to compensate for it's initial length being less than the stock EX250 shock. It will have an Eibach spring for the correct weight of the bike, and my weight. The stock rocker, dogbones and swing-arm will be kept. If it needs to be re-valved for the difference in weight or geometry, I may eventually do that. I have to believe that it would be a superior shock to the stock, nonadjustable shock that comes on the Ninja, so it should be a good improvement.
Also, @Somcai I have read your postings about that before, and agree. I am still learning, and do not have all the answers, so I ask questions and read as much as I can.
I had Jamie Daugherty set up a CBR600F3 rear shock, converted to clevis and resprung and re-valved for my VTR250 Interceptor that I currently race. It does really well, and I may add cartridges to the front forks for it, also as I transplanted 37mm CBR600F1 forks when I built it. Anyway, enlighten me, on this linkage dilemma, hehe.

Originally Posted by pattonme

shocks are valved not just for spring but also wheel rate (aka linkage ratio). I'd say get a copy of Tony Foale's chassis dynamics software and go measure the various parts. But maybe R&T or Spears etc. have already done that and can share.

Say the EX shock moves 1/2" for every 1" of wheel and the GSXR moves 2/3". The valving and flow characteristics of the pistons are different.

this might be useful reading

http://www.promecha.com.au/leverage_linkages.htm

Originally Posted by Somchai

From Matt's link, very interesting:
"Yes, the front leverage ratio. The forks are not vertical, so the fork springs have to compress about 1.1mm for every 1mm of vertical axle movement. That means the effective spring-rate at the front axle is about 20% greater than the sum of the fork spring rates."

Charlie, Changing your dogbone length will change the leverage ratio curve of your rear suspension. This is not always bad, but it is a kind of shot in the dark. The golden rule of making changes with suspension is to only change one thing at a time. That way you more fully understand the effect that your change had on your suspension. The main problem with changing the shock and the dogbones at the same time is that you can easily get lost in trying to optimize your suspension. This is because several things can happen. Both changes may improve your suspension (like winning the lottery!), one change may improve your ride quality and the other may have the opposite effect, or both things make it worse. If the suspension is worse, how do you know what to change in order to get get an improvement? If you win the lottery and both changes improved the suspension, that is good. But if you want to improve it even more, the same question will come back to you: Which thing do you change to make it even better. Your approach of lengthening the shock is a good approach in order to keep from having to change the dogbone length. However, lengthening the shock is generally done in one of two ways: Changing to a longer clevis or lengthening the shock internally. If you only change the clevis length, there is the possibility that the travel of the shock itself may limit your suspension travel compared to stock. If you change the travel internally, then you won't run into total suspension travel issues. And of course while you're in there, you might as well get the valving changed to match your bike's needs.

The lure of the classic OEM shock swap is the cheapness. The reality of the OEM shock swap is that you almost never get what you really want. It's more like "winning" with one of those scratch-off tickets and the prize is that you only won another scratch-off ticket to try all over again. I know very well that my own efforts at putting F3 cartridges in my forks and getting exactly what I want first time out is a little bit like trying to win the lottery and I'm pretty certain that I'll have to do some development to get something that really works well. That's why I just ordered some cartridge emulators to use as an intermediate step for racing while I develop the cartridge setup.
You may want to consider to have the valving changed at the same time that you have the shock lengthened. Using a pro's knowledge has its benefits in that regard because you're more likely to have something that works very well right out of the box.

Having said all that, one thing to keep in mind is that the 250 Ninja is an extremely easy bike to ride and unless we really screw things up, it is relatively easy to ride around the problems we've created for ourselves. That kind of makes it easier to take a gamble on cheap suspension "upgrades".

Somchai, one thing that that article does not point out is that the fork "leverage ratio" actually changes with suspension travel under braking due to the bike pitching forward and steepening the steering head angle. Certainly one could argue that this is the most important area to consider in racing applications. The more the fork compresses, the closer it gets to a 1 to 1 movement, making the front leverage ratio slightly progressive in this situation. And that's not even considering the air gap in the forks which would have a much more progressive effect on suspension travel. It would be very interesting to look at the how the combination of change in steering head angle and the compression of air in the fork have in producing a progressive "front leverage ratio".

[Somchai]

Originally Posted by tgold

Somchai, one thing that that article does not point out is that the fork "leverage ratio" actually changes with suspension travel under braking due to the bike pitching forward and steepening the steering head angle. Certainly one could argue that this is the most important area to consider in racing applications. The more the fork compresses, the closer it gets to a 1 to 1 movement, making the front leverage ratio slightly progressive in this situation. And that's not even considering the air gap in the forks which would have a much more progressive effect on suspension travel. It would be very interesting to look at the how the combination of change in steering head angle and the compression of air in the fork have in producing a progressive "front leverage ratio".

Thank you to bring this to mind, but anyway the fact by itself is interesting at least.

[Somchai]

There's another thing to talk about and before anybody is telling me it has nothing to do with suspension, yes this is right, but it is also an important point for riding quality and safety.
Did one of yall once measure the distance from the pivot of the swing arm to the center of the rear axle to ensure that the rear tire adjustment is straight?
After I'd ride around 5000-6000 km (3500-4000 miles) I saw that the profile of the rear tire on one side (right) was more used or down than it was on the other (left).
Also my feeling was that it is different to turn left than it was in right corners.
So I'd search in the net for a reason and on German MC-websites I found not less riders talking about the adjustment-marks on the swing arm are not always correct.
After that I went to a small shop here to get a tool made with which I can measure the distance from the swing arm pivot to the rear axle (see the attached picture) and with this measurement now I can see that the right side is 2 mm too short, means it must be adjusted 2 mm more backwards.
The tool is plugged into the pivot holes of the frame and then adjusted to the rear axle, checking both sides are the same measurement.
A second check with the laser after the adjustment shows that the chain is absolut straight.
So if one needs the bike in the best condition check for more than only the shock and the fork.

[Yamahawk]

Originally Posted by Somchai

There's another thing to talk about and before anybody is telling me it has nothing to do with suspension, yes this is right, but it is also an important point for riding quality and safety.
Did one of yall once measure the distance from the pivot of the swing arm to the center of the rear axle to ensure that the rear tire adjustment is straight?
After I'd ride around 5000-6000 km (3500-4000 miles) I saw that the profile of the rear tire on one side (right) was more used or down than it was on the other (left).
Also my feeling was that it is different to turn left than it was in right corners.
So I'd search in the net for a reason and on German MC-websites I found not less riders talking about the adjustment-marks on the swing arm are not always correct.
After that I went to a small shop here to get a tool made with which I can measure the distance from the swing arm pivot to the rear axle (see the attached picture) and with this measurement now I can see that the right side is 2 mm too short, means it must be adjusted 2 mm more backwards.
The tool is plugged into the pivot holes of the frame and then adjusted to the rear axle, checking both sides are the same measurement.
A second check with the laser after the adjustment shows that the chain is absolut straight.
So if one needs the bike in the best condition check for more than only the shock and the fork.

That's a nice tool to have! I like it, and it should do well to check the rear wheel alignment to make sure it is true and square. Thanks for sharing, Somchai!

[cbinker]

really wish you could just swap the spring on the stock shock.

[tgold]

Originally Posted by cbinker

really wish you could just swap the spring on the stock shock.

You can. It just isn't worth the effort.

[tgold]

Originally Posted by Somchai

There's another thing to talk about and before anybody is telling me it has nothing to do with suspension, yes this is right, but it is also an important point for riding quality and safety.
Did one of yall once measure the distance from the pivot of the swing arm to the center of the rear axle to ensure that the rear tire adjustment is straight?
After I'd ride around 5000-6000 km (3500-4000 miles) I saw that the profile of the rear tire on one side (right) was more used or down than it was on the other (left).
Also my feeling was that it is different to turn left than it was in right corners.
So I'd search in the net for a reason and on German MC-websites I found not less riders talking about the adjustment-marks on the swing arm are not always correct.
After that I went to a small shop here to get a tool made with which I can measure the distance from the swing arm pivot to the rear axle (see the attached picture) and with this measurement now I can see that the right side is 2 mm too short, means it must be adjusted 2 mm more backwards.
The tool is plugged into the pivot holes of the frame and then adjusted to the rear axle, checking both sides are the same measurement.
A second check with the laser after the adjustment shows that the chain is absolut straight.
So if one needs the bike in the best condition check for more than only the shock and the fork.

You're right Somchai. I have a similar tool for the same reason, but I like some aspects of your design better. Looks like I'll have to make some upgrades to mine.

[pattonme]

I thought everyone knew the swing arm marks were painted on by a drunk pixie hanging upside down by one leg.

They are the same price point as most of the other options (Ohlins, JRi) out there (~$600 or 1000) but Nitron has Ninja 300 shocks you can install and have confidence in the results. Compared to bodging an eBay shock together it's no bargain but those are the breaks.

PM me if you want specifics.

[Yamahawk]

Originally Posted by pattonme

why all the fascination with this GSXR spring or that? Buy an Eibach at the correct ID and correct rate. They are like $60. Otherwise shouldn't there be a thread that documents all the relevant shock springs, their dimensions and rates, and suitable rider weight range so folks can reference? Or did I miss it?

I'll absolutely second/third/forth those say to send the GSXR/R6 shock off to get serviced, lengthened (?) and revalved. It's madness to use the wrong item to "save" a couple dollars. If you're going to do it, spend the 350 and do it right.

Some of these 'light' bikes need 5-10mm longer shocks for best chassis and weight balance. I don't know if the 250/300 fall into this category or not.

First, fix the obviously wrong stuff - fork springs and a thick enough oil to compensate probably around 35-40cSt@40. If the frontend now won't track and is skittish when hitting bumps, drill some relief holes in the damper rod.

@pattonme, Matt, I was looking at Eibach's website, and they don't actually make street bike shock spring replacements. They do make dirt bike shock springs, and fork springs... so, what Eibach spring would I get for the 06 GSXr600 rear shock? It is a 40mm shock body, and I believe it is 7"?? long? I would have to go out and measure it to be sure, but if you can tell me how to get one, in the correct spring rate, it would be appreciated. I am going to PM you about the cartridges, also.

[pattonme]

you want hte coil-over family. eg. 0700.225.0550
Measure your current shock spring to make sure but it should be 2.25" ID but some are 2.5".

[Yamahawk]

Originally Posted by pattonme

you want hte coil-over family. eg. 0700.225.0550
Measure your current shock spring to make sure but it should be 2.25" ID but some are 2.5".

i found the spring coil over section, now I have to decide spring rate. The GSXR600 had approximately 4" of travel, i am having a more difficult time finding the travel of the EX250 shock. Does anyone have the rear spring travel for the EX250E-F series?

[pattonme]

the gsxr had 4" of WHEEL travel. only about 60mm of shock travel. If you're going to do this task you really need to start making measurements and get Tony's software. By guess and by golly is the Internet way, I realize, but why not do it right?

[Yamahawk]

I had seen his software a couple years ago, it seems like he has some additions to it now. If I was going to modify the suspension myself (valving, length change) I may consider plunking down 99 euro's for it. I know the stroke of the shock would determine whether it will work like it is. However, I am not sure what the EX250 stroke is until I pull out the shock and measure it. If the two shocks had comparable stroke, or if the GSXR600 shock was longer stroke, it would be acceptable. I guess I should just send it off and have it set up right. That will have to wait for a bit. $320 is what I can have it done for, and that is with provision of the shock, and I want the cartridges for the front forks first.

[Somchai]

Matt I agree with you, not one ever made real measurements of what they did.
But it's like always, one starts to modify anything talks about it and since, for the main reason, the mod is cheap so all the sheeps follow (in happiness).
I've been asking those who did it about the measurements more than one time, but (what is the lonely caller in the desert?)...
So better just leave it like it is.

[Somchai]

I would like to bring 2 older posts back to mind.
One about how the Gixxer and Ninja shock's normally mounted: https://www.ninjette.org/forums/show...4&postcount=26
But much more important, a post about a compare of the shocks we talk about: https://www.ninjette.org/forums/show...63&postcount=1
I beg those to read, who'd contradict me about the ride-height with the GSXR-Shock.

[pattonme]

unless you're deliberately lowering the bike, you're nuts to use a shorter length shock. Unfortunately the second post makes no mention of what model shock was employed.

You can't source and rebuild/respring a GSXR for much less than a new shock from Sportisi US. So why bother when a proper solution is at hand?
http://sportisimotorsport.us/index.p...ex&cPath=15_17

For the ninja 300, even with my discounts the JRi, Ohlins, or Nitron may be seen as too much and thus I can see the attraction of going with some kind of retrofit.