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Yamada
01-27-2014, 03:52 PM
I have a question for the suspension specialist here. Here are 2 pictures of Yamaha YTM-225DX shocks.
Which spring is harder?


185155
or this one
185156

DohcBikes
01-27-2014, 06:21 PM
That would depend on the diameter of the wire in the spring, number of coils, free spring length, and even age and steel composition.

From the pics, I would say that judging by the wire size and less number of coils, that the grey spring has a higher rate, and discounting shock valving and preload, would be stiffer.

dave ytz250s
01-27-2014, 06:23 PM
I'd say the black one, because it has one more coil.
I might be wrong, I'm no specialist.

MojaveRider
01-27-2014, 06:31 PM
I'd say the black one, because it has one more coil.
I might be wrong, I'm no specialist.

More coils = softer spring

dave ytz250s
01-27-2014, 06:37 PM
More coils = softer spring
Oh thanks, I thought that for the same diameter wire if you have a longer wire compressed to the same height it would be stiffer

DohcBikes
01-27-2014, 07:02 PM
For a single rate spring, the actual spring rate stays consistent throughout the travel, regardless of how far it is compressed. Same diameter+more coils =softer.

Of course these are not single rate springs, so it will be harder to judge by just counting coils and comparing diameter, and the "stiffness" felt would be a combo of the shock and spring assembly.

I'm stickin with the grey one LOL