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Discussion Starter · #1 ·
Hey guys.
I had a really bad day on track Friday, almost high sided while riding the rumble strip and then later went straight on at turn 1 (collie motorplex Western Australia) when the rear tried to overtake me under braking and downshifting.

I am bottoming out the forks under braking and these have allegedly been worked on by race tek?
Any how, does anyone have any recommendations for a stiffer front spring? I’m 100kilos so not exactly light.
I believe I need 10lb springs but don’t know if that will be enough…..

with the rear locking up, I think my slipper clutch may be iffy but saying that if I’m lifting the rear on the brakes maybe it cant work properly.

to top off my bad day, someone was helping me put the bike on its stand and only hooked into 1 of the bobbins. Hey presto my bike was laying on its side on the floor.

I ended up going home about 2pm. The omens were against me and it was just a matter of time before I crashed.

Tire Wheel Vehicle Automotive lighting Automotive tire
 

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meh, not too bad I guess you could have crashed, nice track bike, regroup head back out

is the bike sprung for your weight?
 

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Discussion Starter · #3 ·
The guy who had it before me was 105kilos and had all the suspension worked by race tek whoever they are.
the rear is perfect. The front not so much.
 

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welp, thats where you want to begin or you'll be chasing your tail all day long, no jokes, that's the one component you cannot cheat on or that goes by your body weight, they work in ranges obviously if you are borderline then dealers choice, at that point a lot of guys get 2 shocks, and see what works best for given conditions, after a while you know and set it up night before whatever..
 

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"I believe I need 10lb springs but don’t know if that will be enough"
What do you have right now?
 

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How do you know your bike is bottoming ? Do you have a zip tie on a fork leg ?
If your forks are riding too low the rear will ride too high and lift. Stiffer Fork springs push the rear down.
Whenever the rear tyre bites, under hard braking, is a good thing. Watch the pros, their holding the rear straight and in the air.
Here is the Race Tech Calculator for your 100 kg, intermediate rider, K5 fork.
Recommended, Front spring rate,0.91 Kg/mm.
STD spring rate, 1.0 Kg/mm.
Springs are not marked , so you need to get them tested to see what they are. Google fork spring tester. ( I guess 0.91 Kg/mm is too light. )
Race Teck are in CA USA.
My forks are riding very low and I have wound the pre load all the way so this is my first job for 2022. This place is my recommended contact in Bris.
 

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Discussion Starter · #7 ·
welp, thats where you want to begin or you'll be chasing your tail all day long, no jokes, that's the one component you cannot cheat on or that goes by your body weight, they work in ranges obviously if you are borderline then dealers choice, at that point a lot of guys get 2 shocks, and see what works best for gicent conditions, after a while you know and set it up night before whatever..
i am aware of this however the bike felt fine and the previous rider was a similar weight to me. It’s only as I have pushed on its now not doing as I want.
 

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Discussion Starter · #9 ·
How do you know your bike is bottoming ? Do you have a zip tie on a fork leg ?
If your forks are riding too low the rear will ride too high and lift. Stiffer Fork springs push the rear down.
Whenever the rear tyre bites, under hard braking, is a good thing. Watch the pros, their holding the rear straight and in the air.
Here is the Race Tech Calculator for your 100 kg, intermediate rider, K5 fork.
Recommended, Front spring rate,0.91 Kg/mm.
STD spring rate, 1.0 Kg/mm.
Springs are not marked , so you need to get them tested to see what they are. Google fork spring tester. ( I guess 0.91 Kg/mm is too light. )
Race Teck are in CA USA.
My forks are riding very low and I have wound the pre load all the way so this is my first job for 2022. This place is my recommended contact in Bris.
yes, cable tie on fork leg, sits at The bottom on completion of a session. No wheelies.
The issue I had was like I was backing the bike in on downshifts and hard braking. My slipper felt useless as well. My thinking was that as the forks were bottoming out, there was less weight over the rear making the slipper redundant due to the lack of weight on the rear wheel.
Your post is information gold. Thanks very much for digging all that out, I’ll have a play today :)
 

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By the thread title, I expected much worse. Any track day with no get-offs isn't a 'bad' day. Slipping off the stand in the pit? That's an embarrassing day, that's all. :p
 

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I am not sure but from my weight and behaviour of the bike, that was what was suggested to me from a suspension guy at the track.
10lb spring would be 4.5 Kg/mm. Maybe tuner said 10 Kg/mm which is the STD rear shock, spring rate.
Start a log book and take notes. (y)
No wheelies ? What is the point of living ? 🤣
 

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Discussion Starter · #12 ·
I was going fast haha. Deliberately keeping the front down :) it’s geared -1 on the front and +3 on the rear so it likes the odd wheelie or two haha
 

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It's possible they had RaceTech valves installed, but skimped on springs. You should get to bottom at some point, but not often. Good shops will be able to measure the spring rate and tell you what you have. Start there.
 

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i am aware of this however the bike felt fine and the previous rider was a similar weight to me. It’s only as I have pushed on its now not doing as I want.

welp, if you're serious about this you want to KNOW what's what, know what spring rate you have, what rates are available, what you want to accomplish and why, this is something one cannot and does not want to guess on.. know who made the spring you are using and what its intended for, not all springs are equal.. you cannot move on this without a base, and that base is a spring rate and style within your weight range and goals..

once you have this base then you can make intelligent decisions based on what its not doing or what you want it to do..

this is it right here, horsepower, braking all that is out the door unless you can keep the power to the ground and the bubble up through the turns, remain in control at all times, braking performance is affected here as well, you have to know what your running and why front and rear otherwise you do not know where to go to achieve a desired result..

maybe read some motorcycle racing suspension books, articles, videos and or journals to have a better idea what's going on here exactly, frankly if you're serious about racing or track days you want a good aftermarket suspension or at least the R forks and a good ohlins shock or equivalent, maybe just performance internals, you'll never be happy with performance until you run this equipment..

learn what settings affect what, when, and how, so you can make adjustments and have the best grip and handling possible...

the fact you ask tells me you need to do some research and educate yourself on the entire chemistry of suspension and handling, once up to speed you can make educated decisions on which direction to go when you are not up to speed or competing where you want to compete.. even street riders should have general knowledge of suspension simply for wet and dry riding situations to keep upright at all times..

there is no way for anyone on this forum to help unless they know your base setting and equipment then exactly what you are trying to accomplish.. impossible

plenty of knowledge on youtube some good some bad but knowing what does what, and how settings affect dynamics is must have knowledge, reading tire wear so forth, air pressure dynamics, temps, compound selection, all that matters unless your content with back marker plate status.. of course everyone has their own plan of attack and their own way of doing things you will develop your own but you must learn the basic fundamentals first, then advance.. it's all easy enough..

learn how shocks work and what their role is
learn the various settings and what their roles are
learn the synergy of it all, how one thing affects another, braking vs grip vs contact
learn how to apply it all to your style of riding..

in the end your goal is to keep the tire patch as large as possible at all times and under control even under the hardest braking, sliding all that comes later, learn the basics, go from there
 

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Discussion Starter · #18 ·
Mate. Not being funny but your post insinuates I’m a rank amateur and an idiot.
I’ve been riding for nearly 20 years and run in the fast group on track days. I’ve ridden circuits through Europe and Australia.
yes this is a new bike to me, I believed it was set up as the sag was perfect and the and spring rate felt fine, unfortunately I can not ask the previous owner as he is now deceased through cancer.
his height and weight was extremely similar to mine and knowing how much he has spent on this bike I believed and still do believe that it is set up well.
the aftermarket nitron rear shock is brilliant. The forks have been worked on and until the weekend were perfect. It is only now I’m pushing on with this bike (that I’ve only ridden 4 times) due to starting to feel comfortable.
I fully understand what rebound, compression and preload is. I don’t need to familiarise myself. I am however no expert so sought some supposed expert guidance. Forgive me for hoping someone with a similar weight on the same bike had also suffered similar problems.
do me a favour and don’t be so condescending. It’s a shame as I normally agree with what you usually say but this time not so much.
 

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Discussion Starter · #19 ·
Also as for using ohlins stuff, I can not afford that.
Most modern suspension is perfectly adequate when set properly for almost all riders. I’ll never be a Troy Bayliss so doubt I’ll need the Gucci stuff. Besides that, I have the BFF forks on my 2017 R and actually don’t like them all that much. I prefer the BPF’s in my 2013 Gsxr 1000.
Also I don’t deliberately back it in, or slide. I’ve never said I do. That was a bi product of the forks bottoming out!
 

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I think Twisted is a cowboy from Texas, (with the greatest of affection) In Australia "cowboy" has a different meaning.
I'm on this forum to learn, but also for my amusement ! And looking back to my early posts they could have been better thought out and less random. 😁
As a bush basher (amateur) all my life, I am only now (58) trying to learn how this stuff works.
I too believe the STD suspension is better than my ability can overcome.
It does seam, some professionals, are only in it for the income. Although it is hard to express what "the feeling " is you are experiencing in a corner. And conveying this " feeling" to a tuner.
Last track day, Dec 5. I lost the front wheel !, for the first time on a road bike 😲. But recovered it and didn't go down. 😅
I believe it was understeer as I had gone one click harder on rear rebound, which will cause this. (trying to fix the lack of front spring rate, WRONG)
Lots of info out there, you need to hear something that corresponds with what your feeling.
Dave Moss Tuning Homepage - Dave Moss Tuning
* This 101 lesson by Max McAllister, I printed out and carry with me. *
 
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