front spring sizing specs vs. racetech

[goosefartfan]

If the specs say it's a 38mm front spring, why does racetech list it as a 31.7mm (32mm) spring?

[reelrazor]

It''s a 38mm fork tube.

That's o.d. (outside diameter)..

The springs need to fit inside of them...and there are 38mm fork tubes with differing wall thicknesses. So, racetech goes by diameter of spring vs. diameter of fork tube...

[pefrey]

What he said.

[goosefartfan]

thanks!

I didn't get any automatic notices, so I just found your answers!

What I'm trying to do is save $!

So, if I've got a 38mm OD tube, why does racetech call for a 32mm OD spring? 6mm seems like a lot of space!
It would seem like something larger would also fit into the tube. I'm trying to find used springs on eBay and looking to expand my options. Racetech calls for a 32mm OD by 340mm length.

Do I have any wiggle room?

[reelrazor]

OD is "Outer Diameter"...

The tube has a wall thickness of a couple mm-[prolly more like 2.5mm. 38mm minus 2.5mm-on each wall involved in the diameter-equals 33mm ID (Inner Diameter).

The spring's OD must be less than the tube's ID..so a 32mm OD spring is perfectly logical (spring can't be a friction fit in the tube).

[goosefartfan]

OK, thanks.

I had no idea of the wall thickness.

Re: length, if some spring was a little shorter, could I use a PVC spacer to make up the length, or is that opening another can of worms?