Rim Swapping - ERD Difference?

[SimonC]

I have a pair of Chorus hubs on 36h Open Pro (ERD 604/5mm) at the moment. I'd like to swap the rims out for a pair of NOS 36h GP4s I have hanging in the shed (ERD 612mm).

The existing spokes on the Open Pro wheels come to the end of the nipples. Will I be able to get away with swapping the rims over without needing to buy new spokes?

[regularguy412]

IMHO, new spokes and nipples = cheap insurance. Do it.

Mike in AR:beer:

[ergott]

Way too big a difference to work.

[Gothard]

You may want to check the tables for the front at least, maybe you can get away by doing 2-cross instead of the 3-cross your front wheel most likely has now.

[Peter P.]

Looking at the Sutherland charts, it looks like the spokes will need to be 4mm longer to work with the GP-4s.

You don't usually get such a wide choice of spoke lengths when building a wheel. You can sorta get away with a 2mm change, but that's SORTA.

I don't think it will work.

[SimonC]

Thanks for the comments - sounds like I'll need new spokes, so I probably won't bother swapping the rims