2014 Very Soft Front Springs... Normal?



Trying to dial in my suspension sag on my gen 2 busa.

The standard rear preload setting seems about right with 35mm of rider sag. The front forks were very soft in comparison with over 50mm on standard settings. I've wound the front preload down nearly all the way and am now around 40mm of rider sag.

Im 260lbs with gear on so i am very heavy. Are the front springs known to be set light in comparison to the rear?

Any other heavy riders with setups i could copy to try out?

Thank You for any assistance.


1.10 kg/mm for casual street
1.15-1.20 kg/mm or for more precise riding

Upgrading the springs will cause your forks to be oversprung and under dampened. Which may or may not be a cause for concern depending on your riding style and time spent on tuning. In addition to sixes recommendations, there's another option by a company called traxxion. You can either have them set it up and respring, revalve the forks for about 700, or you can do it yourself with their ready to go kit for about 1000. The difference between the two is the lower price option is done to your exisiting fork internals. Option two is drop in.


Like @sixpack577 said, the stock rear spring on a gen2 is rated for a 230lbs rider or so, while the front won’t even handle that. You need new springs and possibly a revalve. Racetech’s website is a good source of info and traxxion dynamics seems to also have a lot of happy customers, as well.

Mr Brown

Closest RT Center to you is called PDQ Motorcycle Developments, in Taplow, Berkshire. The other is in the Sheffield area.
Click Here for the interactive map on Race Tech's website.
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That's perfect thankyou. Ordered the springs, spring compressor, damper rod holding tool and some 5w fluid. All ready to go hopefully.

Anything else you think would be useful to know or have?


I personally would recommend you go with the 11 to 11.5N/mm springs and installed preload at 9mm. A Revalve is a big benefit on These 20mm Cartridges...as you are in the UK....you should give K-Tech a try. The Quality is superior. The K-Tech FCV is a nice Option too...but not necessary.

Be Aware that either on the comp. and on the reb. Adjuster you are not limiting any flow above 7clicks out.

You will not benefit from thicker oil (5W is the Option). If you use heavier oil you will lose damping because the shims are not able to Close against the Piston.

You must also resprung the shock. A regular ohlins spring or ktech spring is fine for that


Is the rear shock re-spring a necessity? Feels pretty good to me and can easily achieve the required sag.

Ktech dont list fork springs in those specs which is frustrating


I could check the Options later in regards to the front.
Shock respring is necessary because you would have way to much preload with your weight and the correct sag - you maybe would also loose free sag. that would be very bad.


I've ordered a 15.2kg shock spring(15.6 was recommended but only available as 15.2 and 16.1) to go with the new 1.1kg springs on the forks.

Do the racetech fork springs go straight in, or does it need spacers calculated and cut?


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