I am almost done weenying by xc hardtail, and the missus is having trouble keeping up with me.

She has a Trek 6500 WSD and was wondering what upgrade would give the biggest performance improvement? I was thinking wheels or forks as they are both **** heavy on her bike.

Yep, wheels and forks.

Ps I just got new wheels, was thinking of putting my Mavic XM317 – deore hub wheelset on her bike, but not sure they are vastly better.

maybe you suggest the wife looses a few pounds 🙂

thinking of putting my Mavic XM317 – deore hub wheelset on her bike

Not going to make much of a difference.

the missus is having trouble keeping up with me

Ride more, eat less will have more of an effect. Or you could not beast her as much and take it easy for a few weeks?

take up the rear and let your missus lead the way.

That level of bike offers lots of places to drop weight but the above are correct. Get an air sprung fork to lose weight and give true adjustability and a set of basic Fulcrum or Mavic wheels will drop a bunch of weight for a spend of £150.

when you go riding with your wife, put your wheels on her bike & hers on yours ?

What wheels are on her bike at the mo?

Get her a comfortable saddle first make it plesant for her

but lightweight wheels and tyres are a good idea, the tyres may well be the cheaper option and most effective

I did put Rebas on my wife's Kona (shedding tears as I cut the steerer to fit) and also put on Kevlar tyres. Both together did make a fair reduction. It didn't cost any real money as the parts had become spare after a rebuild/upgrade on other bikes. Psychologically its lighter and its easier to handle and (very importantly!)easier to lift over fences but it hasn't made much difference to her riding speed. Wheels would be the next option but you start to get into a lot of expenditure and have to consider if weight is really the main issue. Does she use SPDs – does she ride as often or have the same skill level or want to keep up? Can she keep up if she is on your bike and you on hers – or similar swap if sizes aren't compatible.

I've shed a load of weight off my bike and I still can't keep up with my son. (and just to confuse the issue there is barely any difference in my speed over a given ride if I am on my lighter bike or his heavier one – 1 minutes difference comparing 2 timed runs on the black at GT for instance)

Swap bits with your bike? or go out with on her on your recovery days.

I always laugh when I see the Hubby on a £2K machine and wife looks like crying trundling behind on a steel 40 lbs pile of crap.

Trek 6000 series is fine but deffo light wheels and bits but compare this with the cost of a better bike if she rides alot with you etc.

next time your thinking of upgrading your bike, dont. upgrade hers, you selfish person! 😆 😈