Does fork length change with frame size?

[gmtfd]

I recently picked up a Raleigh Mirage 1990 which I've stripped down, but I've come to the conclusion that the frame (23") is too big for me.

There is a 21" Mirage frame for sale locally. I'm wondering whether the fork from my 23" bike would fit this frame? Is the same fork generally used across all the different frame sizes for a given model, or does the fork length change?

Any advice gratefully received.

 

[integerspin]

You can tell a Marin frame size by how long the headstock is, the fork blades are the same length.
Haven't had other bikes of different sizes to know how common that is.

 

[MatBH5]

Re:

The fork leg length will be the same as long as the wheel size remains 26”, and the bikes are similar age/geometry. Generally going from a 19” to 21” to 23” in the same model/manufacturer, and year, there will be no difference in this aspect.
However, the steerer length will change with the headtube of the bike, which gets longer as the size increases.
In your example, a 23” to 21” using the same fork, you might find the steerer a bit long - but as long as the threaded portion is appropriate this should still work but you’d need a spacer in the headset stack, under lock nut.
As the suspension era came along, certainly after 1990, fork axel to crown did lengthen as the frames became ‘suspension corrected’ but you’ve no need to worry in 1990.

 

[gmtfd]

Re:

Thanks a lot for the info, I thought the fork blades probably stayed the same but hadn’t thought about the steerer tube.

 

[Corblimeyguv]

Re:

Your steerer tube may be a bit longer than the other.

If it is just use some spacers to take up the extra