Ask Dave: Changing Motorcycle Fork Springs

One of the top questions in Dave's inbox regards fork springs. Are the stock springs correct for my weight, people ask. Weight, while important, is one factor in the overall equation.

[robertcostello]

I have recently bought a yamaha fz1s which is extremely fast compared to my previous bike. The handling was terrible when I got it but now is amazing thanks to your videos. Many thanks 👌👍

[chriscox]

Fantastic videos dave. This one is vital info thats much needed for all us new riders learning the bike.

[PistonSlap]

Good info Dave! I just put new springs for my weight all the way around on my 2013 ZX6-R. Now I need to get back to the track and dial it in.

[David.Horne]

I love your honesty and direct approach. We need you in Australia lol

[subocito]

This is probably a really big question, but...
I'm not sure I understand the difference between Compression and Preload. I understand the mechanics in the fork when you adjust them, but not quite the effect that it has.
Why would it not be enough to turn the compression in, if you bottom out the fork? (And ofcourse I've watched your videos on both preload and compression, but I still can't figure out when to adjust what)
Other than my troubles understanding, the videos are amazing. I've learnt so much more after watching your series.

[maakamccadless]

.Dont know if you are still out there Dave, , I bought a used Honda cb 1300 X4 SC 38. when it arrived I noted it sitting low down, on first ride, not only did the water boil after 6km in Thailand, but the forks bottomed...they are not adjustable. not sure of water problem, but forks need new springs..is Progessive ok..I dont look at brand just buy if I can locate...will I need new seals as well..

[eb-vm]

Good video and good explanation, thanks for this!

[brouder]

Hi Dave! Thank you very much for your videos.
I have a CRF450RX 2022 and I use only half of the travel on my forks. Does changing for a lighter density oil will help?
Thank you!

[jwdiho]

You mention taking preload all the way out or all the way in. Is it more important to be at correct sag or correct fork travel at full compression when riding hard?

[jaakkopusa]

Hey Dave, can you give me an educated opinion? Should I also put thicker fork oil on my year 2004 Suzuki gsx 1400 with 20mm raise blocks on rear springs, when I change for stiffer fork springs 0, 73->1, 1kg/mm or should I first experiment with original w recommendation? Great videos and if you ever organize test&tune days in Finland I will definetly attend on it

[MT--WesleyCrumblebee]

Hey Dave. Running as you advised for my 2016 ZX10 for the forks. But with 5 in preload, 2.5 out rebound and 2 out comp, im getting 15mm of sag because the springs are so heavy, BUT im getting mechanical bottom out under heavy braking. The forks feel quite aggressive in the canyons/mountains through bumpy turns so Im concerned with the comp or rebound skipping over some rough patches, but I also dont want to back out the preload further because I am making full use of the travel with braking.
I dont know whats worse, pushing the front over rough patches or tucking it under braking :(
98kg in gear. Shock is at 25mm sag. 1.5 comp out, 2.5 rebound out. Rear feels good.

[robmuhfacka]

I have a question I seriously need some help with with my zx10r and it seems you're the Guru 🙌 I'm having the exact opposite problem I have my preload turned out and still have little to no rider sag on my bike even hitting speed bumps with the front tire my zip tie only comes down maybe a quarter away from the fork tube 🙃 I've been trying to dial in the front and back to my weight and I just don't think I'm going to be able to shake this stiff front. It performs well enough for me but I've noticed pains in my palms and some other things from it being so rugged. Also where I'm located the roads aren't the best around so it's been a bumpy ride up front and Cadillac in the back 😅 but for this reason I'm afraid of squatting and running wide 🤦‍♂️

[mrschwifty]

Thanks for the videos you probably saved me from a very bad day. Got my first street bike in July a 22 zx6r. And at 190 lbs Preload maxed out I am able to bottom out the front end on the street just messing around. Could you recommend a spring rate better suited for my weight ?

[apexhunterk]

great vids Dave. In really learning alot but I to have a question. I have the 2017 gsxr1000. How do I find out where the fork bottoms out so I can measure effectively to see if I'm in the 20-25 mm range to see how my preload and compression are effected.

[Steve-eced]

I know this video is old but hopefully you'll still see this... At what mileage should I service my forks? I just purchased an 8 yr old bike (R1) w/ 14k miles. Everything feels right but I want to be proactive on my maintenance.

[HORNET]

Hi Dave, firstly, I really enjoy your vids. Secondly, a question on this video. Should the preload adjuster be treated as a fine tuner once you've changed out for a heavier or lighter spring, starting from all the way out then increasing until 120-130mm of travel is achieved?

[kostasrestas]

hello my friend!
i have an xt660z tenere 2008 and some days before i replace the forks and the wheel with forks and wheel from wr426f
now i have to change the springs with stiffer ones because tenere is way more heavy and i'm 100 kilos.
but i don't know what springs i buy..
what i have to check, calculate or consider before i buy???

[patdudley]

Hi Dave. Id like to ask.... As forks are constantly improving over the years. wondering should I upgrade the springs and re-valve the ones on my old CBR900RR (SC33) or swap the front end for something like 09 CBR1000R USD forks (radial) and front wheel. Ive done this before on other bikes but can a 98 front end ever be as good as these later ones ?. Total road use for me but I like to improve older bikes in any way I can as far as Performance and handling goes

[johnwoo]

HI Dave I thank you for all the information you give us
i have question to ask you
i have 2000 kawasaki c10 concors every time i hit the bump or pad hole the handle bar shake what coud be the problem
thanks

[aswints]

How can i soften the front forks. I tried changing fort oil but still ita quite stiff.. please help. I am using a 400 cc motorcycle in india which wiegh roughly around 180kgs. But stll my bike is giving me a rough ride. Indian roads are filled with potholes and bad pathes and i need a suspension which can absorb them and give me s comfortable ride. Please help..