Premium Member howworkclutch Posted May 19, 2015 Premium Member Share Posted May 19, 2015 about 200 in full gear. i mostly bomb back-roads of questionable quality. -HowWorkClutch Link to comment Share on other sites More sharing options...
pattonme Posted May 19, 2015 Share Posted May 19, 2015 Consult the bike+rider vs suggest spring rate graph - http://fz07.org/post/34913 OEM spring was measured by me to be 0.72kg/mm despite the EU/US manuals claiming otherwise. Traxxion puts their measurement between 0.7 and 0.75. You'll have to ask Dan@Traxxion for the precise numbers. In any event 0.72 is right where I expected it to be given the behavior of the forks under weight transfer. Link to comment Share on other sites More sharing options...
bmwpowere36m3 Posted May 22, 2015 Share Posted May 22, 2015 Good stuff, glad you got it measured. Time to make a correction in the service manual Link to comment Share on other sites More sharing options...
pattonme Posted May 28, 2015 Share Posted May 28, 2015 Racetech's calculations vs the Traxxion graph - I consider RT's to be minimum numbers and Traxxion's to be maximums. For example, a 200lb rider + 400lb bike = 0.95 (Traxxion) vs 0.9 (RT) If racing or doing lots of track days, go with the Traxxion rate. For pure, lazy, comfy street riding go with RT or 1/2 rate higher. Personally I would recommend .9+.95=.925 for street duty with interests in canyon carving. 250lb rider use 0.95 for street or if you want 0.925 is workable too. Link to comment Share on other sites More sharing options...
bmwpowere36m3 Posted May 28, 2015 Share Posted May 28, 2015 Racetech's calculations vs the Traxxion graph - I consider RT's to be minimum numbers and Traxxion's to be maximums. For example, a 200lb rider + 400lb bike = 0.95 (Traxxion) vs 0.9 (RT) If racing or doing lots of track days, go with the Traxxion rate. For pure, lazy, comfy street riding go with RT or 1/2 rate higher. Personally I would recommend .9+.95=.925 for street duty with interests in canyon carving. 250lb rider use 0.95 for street or if you want 0.925 is workable too. RT's calculator is rider weight, no gear. Does Traxxion's charts assume gear... which I can only imagine is 10-15 lbs. Link to comment Share on other sites More sharing options...
aeisan Posted May 29, 2015 Share Posted May 29, 2015 I just weighed myself with and without gear on. Leather jacket + RF1200 + gloves + boots = 15 lbs, almost dead on. Life is good on 2 wheels! Link to comment Share on other sites More sharing options...
Premium Member howworkclutch Posted May 29, 2015 Author Premium Member Share Posted May 29, 2015 i think my leather jacket + leather pants might put me over the 200lb mark. i ordered 95kg springs and was regretting it, until i ran it all through a calculator and came up with a 30lb difference. this bike mostly does fast switchbacks/tight chicanes. not a lot of "joy rides" but not exactly track day riding either. in june i'm taking it on a week-long camping tour and will have a ton of crap tied to it. so i suspect the extra stiffness will come in handy. if not, i'll sell the springs to someone (at a reduced rate of course) on the forums and go down to a 91/92. i have a fully adjustable showa shock off a buell that appears like it might fit. it was a little soft for the buell (420lbs) but might be just-right for the yam. i'll find out if its a direct fit next weekend. -HowWorkClutch Link to comment Share on other sites More sharing options...
gtmn Posted May 29, 2015 Share Posted May 29, 2015 you will be happy with the 95s Link to comment Share on other sites More sharing options...
pattonme Posted May 29, 2015 Share Posted May 29, 2015 There's an implicit +/-20lb in the figures. Actually RT asks for "in gear" values in their dialog box AFAI remember. Traxxion's is with gear, because what kind of rider goes around naked? Point being, just try to get reasonably close. If Traxxion says 0.95 for 200lb rider, then 180-220 can use that rate, no problem. For street use I just suggest sliding the Traxxion graph downward 1/2 a square, is all. So by Yamaha equipping the bike with 0.7x springs, they basically left out the rider in their calculations. Now if the bike came with preload adjustable fork caps everybody's life would be less complicated. Link to comment Share on other sites More sharing options...
fflier9 Posted May 31, 2015 Share Posted May 31, 2015 hey, clutch, if you decide to sell your .95 springs let me know. Link to comment Share on other sites More sharing options...
Premium Member howworkclutch Posted June 8, 2015 Author Premium Member Share Posted June 8, 2015 I installed them this weekend. I reused the stock spacer as it was close enough. I think i'd be better served with .90 springs, but I can not deny the total transformation of the bikes handling in corners. Its a complete joy to toss it around a series of tight turns. But it sure does amplify the suckiness of the rear shock. I wonder if a stiffer spring would improve things, or if the shock simply needs to be reworked. Its simply too bouncy out back. -HowWorkClutch Link to comment Share on other sites More sharing options...
bmwpowere36m3 Posted June 8, 2015 Share Posted June 8, 2015 @howworkclutch Notice the same with the rear.... especially under "g-outs". Definitely needs more rebound out back. Was the aftermarket spring the same length as the original? Reason I ask, I measured my static sag at ~19 mm up front (stock bike/springs)... which is pretty spot on, however I'd venture that my race sag will be too high. With stiffer springs, the same length as OE, I'd think you'd need a shorter spacer to target your static/race sags. Rear static I measured at 9.5 mm with the shock on "3". I'm going to increase it to 4-5 and see how my sags work out. Link to comment Share on other sites More sharing options...
Premium Member howworkclutch Posted June 8, 2015 Author Premium Member Share Posted June 8, 2015 yeah it was the same length. i followed the instructions for determining the spacer length. unless i did it backward, the static sag was about the same (but not measured). i suspect you'll just get more boing-boing action by increasing the preload on the back. if you unload the spring a bit, it will be softer, but the spring wont be under pressure when you hit a bump. the oscillations will still exist but should be less violent. i think? maybe matt can chime in on this and give a little insight. -HowWorkClutch Link to comment Share on other sites More sharing options...
pattonme Posted June 8, 2015 Share Posted June 8, 2015 more preload makes the shock stiffer so it will move less given the same bump impact.(ed. Constant rate springs are the same no matter how little/much preload they have) So the piss-poor rebound circuit doesn't have to do as much. A softer spring means more travel and thus the shock will oscillate more. Set preload to get proper rider (aka race) sag. If static is way off then revisit the spring rate but you can get away with having the 'wrong' spring up to a point. Then dial in as much rebound as needed to keep the boing-boing-boyoyoyo'ing to a minimum. Link to comment Share on other sites More sharing options...
bmwpowere36m3 Posted June 8, 2015 Share Posted June 8, 2015 Preload only makes it feel initially firmer, but the bottoming resistance and rate haven't change. Springs only store energy... for a given bump, regardless of preload, the spring will store/release the same amount of energy. I think of springs as steady-state/ride height control and the damping circuits as your transient controls. Link to comment Share on other sites More sharing options...
pantheraleo Posted June 8, 2015 Share Posted June 8, 2015 Preload only makes it feel initially firmer, but the bottoming resistance and rate haven't change. Springs only store energy... for a given bump, regardless of preload, the spring will store/release the same amount of energy. I think of springs as steady-state/ride height control and the damping circuits as your transient controls. True, but they travel less. For me at 200, the factory setting of 3 was a bit too adventurous... I'm planning on replacing my rear shock around the 20k mark. With preload caps on the front forks and the preload of the stock shock at 8, I find the (otherwise) stock suspension manageable. I find that if I stay on the throttle through the corners, I don't bounce. O judgment! Thou art fled to brutish beasts, And men have lost their reason. Bear with me. My heart is in the coffin there with Caesar, And I must pause...till it come back to me. Link to comment Share on other sites More sharing options...
pattonme Posted June 15, 2015 Share Posted June 15, 2015 random factoid of the day: The average American is 33 pounds heavier than the average Frenchman, 40 pounds heavier than the average Japanese citizen, and a whopping 70 pounds heavier than the average citizen of Bangladesh. Adjust your spring choice appropriately. Link to comment Share on other sites More sharing options...
gtmn Posted June 16, 2015 Share Posted June 16, 2015 I think someone just called me fat good thing im not sensitive as we all know, yup im 250 Link to comment Share on other sites More sharing options...
Premium Member rowdy Posted June 16, 2015 Premium Member Share Posted June 16, 2015 I finally got a good, long, twisty mountain ride in, and I can attest to the fact that the rear shock came from a pogo stick. I have a Matris on order, but the delivery is already behind schedule. I'm hoping it, along with spring and fluid replacement will get closer enough to good suspension that I can wait until I dismount for the season to send pattonme my forks so he can do it right. Why can't left turners see us? Link to comment Share on other sites More sharing options...
paulibiker Posted June 22, 2015 Share Posted June 22, 2015 Why is Sonic spring calculator so low? 225lb rider, 400lb bike, standard bike, & normal street riding is .80. Link to comment Share on other sites More sharing options...
pattonme Posted June 22, 2015 Share Posted June 22, 2015 I just reached out to Sonic about his calculator. That's clearly wrong. The chart to use is http://fz07.org/post/34913. slide the curve down up to 1/2 a square for single rider and street duty. Link to comment Share on other sites More sharing options...
motorazr Posted July 13, 2018 Share Posted July 13, 2018 RaceTech has updated their web site: http://www.racetech.com/ProductSearch/12/Yamaha/FZ-07/2015-17 They now say: "Stock Fork Spring Rate:0.88 kg/mm (stock) Comments: First Year 2015 FZ-07/MT-07 Models may have lighter .75kg Rate Fork Springs" I know can be difficult to distinguish soft springs from soft dampening. As soft as my 2015 front-end is, my static sag is only about an inch and all the spring-rate calculators I've used say I should be using 0.9 kg/mm so my stock springs are probably correct while it's just that my fork oil is way too thin (5wt should be 15wt). I was tortured by the Japanese during the war, Jack. Not a pretty story. Strange thing is they make such bloody good cameras. Link to comment Share on other sites More sharing options...
pattonme Posted July 13, 2018 Share Posted July 13, 2018 Link to comment Share on other sites More sharing options...
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