Mixing fork springs, good or bad idea?

[RMJay84]

Someone gave me the idea so I'm giving it a go.

In one of my 250EXC's I have 4.6 in the left and a 4.0 in the right for a desired rate of 4.3.

I was actually looking for a set of 2nd hand 4.4's but this might get me by in the meantime.

[Gypsy501]

There is nothing bad about it


Sent from my iPhone using Tapatalk

[eagle]

Have to say i have thought about this more than once, i'm also wonder what if you had more preload in 1 fork ?

[crf450]

Done it a few times over the years with no adverse affects.

[Arctra]

Not a problem. Put the 4.6 (heavier rated spring) in the leg that the brake caliper bolts onto - advice Terry Hay gave me.

[Gypsy501]

From my experience It makes no difference which side you put the Heavier spring in-as all braking force is pushing down evenly on your axle.


Sent from my iPhone using Tapatalk

[hairyone]

I'd postulate that it maybe about the mass of the brake-assembly acting-vertically on that side?
Still, I doubt it would make a noticeable difference; unless there is slop in bushes &/or bearings.

[RMJay84]

The 4.6 is on the caliper side .... I guess I'll wind up the preload on the 4.0 if I feel I need to.

Terry hay is a suspension guru so there's probably some scientific notion behind that idea.

Thanks for your replies all, much confidence inspired, taking it out tomorrow for a test ride.

Still, I doubt it would make a noticeable difference; unless there is slop in bushes &/or bearings.

I rode about 80kms on collapsed front wheel bearings on the caliper side once, the bearing race was rubbing directly against the wheel spacer ... Had to make an asserted effort not to lean (slow single track only) and couldn't use the front brake. It let go 10 minutes into the ride and I'd driven 2hrs to get there, I wasn't going home.

[arrow]

Kawasaki effectively did it with the SFF fork.

air forks will be unless the air pressure is exactly the same in each leg.

[RMJay84]

Gotta say I'm impressed, I wound the preload back to zero on both legs and set it to comfort as per the manual. Preliminary results are great

[Tom68]

It's OK, only because the spring rate becomes an insignificant force deep in the stroke when the loads get serious.

[RMJay84]

How serious?

[Von]

Seek out the science. Springs in parallel v springs in series. Unless the front axle is made out of licorice, you can play with combinations to suit.
Consider some of the mountain bikes which only have one fork.

[Nutty]

From my experience It makes no difference which side you put the Heavier spring in-as all braking force is pushing down evenly on your axle.

Not the issue. Heaviest spring goes above the area of highest unsprung weight. Reduces axle shear load. Terry knows his stuff...

Harley tourer rear springs on the drive side are TRIPLE the rate of the non-drive side. 😳