Equinox

Cheers;
I would like to install a powerTap rear hub, but I like my current wheels. Is it possible to install it on my present wheels, assuming the spoke pattern is compatible?

HillRider

Even if the spoke pattern is the same, the required spoke lengths may not be. You will have to compare the flange spacing and spoke hole radius with your current hub to see if they are close enough. If they aren't nearly identical, about all you will be able retain from your current wheel is the rim.

Equinox

Yes. I'm pretty sure I would need different length spokes. Does that make it impractical?

HillRider

Well, it probably makes the cost impractical compared to buying a complete new wheel with the Powertap hub installed. That's particularly the case if you have to pay someone to do the rebuild. Probably the best bet is to buy a complete Powertap wheel and keep your current wheel intact as a spare or for times when you aren't concerned with power data.

gregf83 

Not a problem at all. Just find a bike shop that builds wheels. I think mine charged around $50-60 labor plus spokes. I brought them a rim and hub and they built the wheel.

Drew Eckhardt 

You can retrofit a powertap hub assuming a traditional rim with uniformly spaced holes of alternating (or neutral) offset and matching spoke count.

You may need to change the pattern:

• The PowerTap requires at least 2-cross lacing on the non-drive side (which is where the freehub body drives the wheel through the torque tube). NDS radial is right out.
• The larger flanges may (the G3 is smaller) require one fewer cross so you don't exceed the nipples' ability to pivot fore and aft in their sockets. For example, 32 hole rims lace better 2X to previous generation PowerTap hubs and can have problems with spoke breakage with uncorrected spoke lines when laced 3X like conventional small flange hubs.

You will need new spokes.

mconlonx

Unsure why you would want to build a PT hub into your existing wheel. Only real reason would be cosmetic, to have rims and spokes matchy-matchy, front to rear. Otherwise, building on the old rim with a hub which has different flange spoke hole diameter, different spoke length, will have some kind of impact on the riding characteristics of the wheel. It may ride/feel similar, it may not even be noticeable, but there will be some subtle or not so subtle difference between the two builds.

Were it me/my bike, I would get a PT wheel and keep the existing rear wheel, built as-is.

Ronsonic 

To do what you suggest rebuild the existing wheel with a new hub (powertap or otherwise) saves the cost of the rim. There is a small but non-zero chance you can save on nipples and spokes too. It would certainly add to the labor cost, or amount of your time required. I'd go ahead and build up a new wheel around the PT and then have a spare wheel. Unless you've just got too many wheels littering your life. But then you're probably the type to want another one, anyway. Or, I would.

Le Mechanic

I've done quite a lot of powertap hub install/wheelbuilds at the shop I work at. The only issue I can see is having a competent local shop that can do said swap. If you have a wheelset you like, it's not impractical at all as long as the rim uses standard type spokes and has a hole count that powertap makes.

Looigi

If you're changing out the hub and spokes, the only thing left of the old wheel is the rim. It depends on how fond you are of that rim as to whether it'd make more sense to get a whole new wheel or not.

andr0id

If it's an easily available rim just by a new one for your PT hub.

I run PT with Velocity A23, but have spare DA hub laced to an A23 if I need it.