OK, i seem to have found the limit of Hope hoops ztr 355s and now have a noticeable flat spot on the rim. its a couple inches and a few mm deep at the worst point. The spokes in the area are now a bit slack.

can the rim be fixed, preferably by myself?
is this a bike shop job?
or do i need a new rim?

You can't really get rid of the flat spot, no. I tried bashing one out recently cos I CBA/afford rebuilding, made it a bit better but still not 100%. It was worse than yours though.

Rebuild time.

I've got one bigger than yours!! Flat spot that is!! Spokes went loose all round area on non drive side. Took to LBS (who has built wheels for me in the past) and he did his best to re tension the wheel. Just about got it running straight again but you can't get rid of a flat spot.

Laced new rim in today and will drop it off for him to true tomorrow. You could just get it trued but the tension wil be out and the wheel could just go.

Wheels is unlikely to "go" IMO, will just be annoying!

Try to find a dedicated wheelbuilder, like wheel craft, these guys have pullers which can pull a flat spot out of a rim. I imagine it will fatigue the alloy tho.

bugger. expensive these ztr rims!

Try to find a dedicated wheelbuilder, like wheel craft, these guys have pullers which can pull a flat spot out of a rim. I imagine it will fatigue the alloy tho.

Really I never heard of that when I was in the trade. Maybe not, given your second point.

just carry on riding on it, will be fine

Cynic-al try a search for 'VAR rim dent puller' if you,ve not heard of it, it must not exist then.

It's work hardening/plastic deformation not fatigue but maybe that's pedantry.

I imagine it would work though but it will weaken the rim. How much of an issue that may be is hard to quantify.

Back to the original Q, the key thing is not to have loose spokes. Then it's a question of whether you can live with the flat spot as it'll be fine structurally.

Thanks j-cru, interesting find. Intended for steel rims according to one post.