I have two options:
– buy/build a pair of wheels for training (and ride my Whippet)
– rebuild my Marin Team Issue from the ’90s and use this bike for training, and my Whippet for racing

What do You suggest? What’s the better choice?

why do you want separate wheels/bike for training?

Ride the bike you intend to race, so you’re comfy, familiar and used to it / any nuances etc. Takes a few things off your mind come race day…

I’d like separate wheels, or bike because I’d wear out my racing kit fast, too fast. I mean, the Racing Ralphs, the lightweight wheelset, chain, etc. So I’m thinking about building a wheelset (&cassette, tyres, chain) or use my older bike for training. Obviously I’d ride my racing machine 2-3days before the event. What do You think?

if it’s wear you are worried about, the transmission takes the worst, so it’s got to be a whole bike.

Or you could just ride the race bike, use cheaper transmission etc, and look after it more (it will be **** all slower, despite what they tell you)

If you are serious about racing, you need a road bike anyway.

I have a road bike, too… and I ride that much. Too much. I think I need to ride MTB, not only racing. 8)

Whole bike. Wear is going to be on the drive train as much as your fancy wheels. Just put solid basic kit on there and train away.

Also, It might be the odd % slower but the training effect will be the same.

The Marin Team Issue has GT forks with 390-400 A-C length. The Whippet has 100mm Reba WC. The difference will be significant. Or I’ll be better on the Whippet if I train on the Marin? 😀

Another Whippet, same contact points, cheaper fork/wheels/transmission.

How does having 2 similar bikes, one with cheaper bits. work out as cheaper to run than one?

Keep kidding yourselves guys…

Depends how expensive the expensive bits are, how cheap the cheap bits are, and how much you can ride your bike.

Someone like CA clearly rides their bike nowhere near enough for the equation to come out cheaper, your situation may well be different.

Running the Marin with V-brakes and older 3×7/8 drivetrain would be cheaper, than the new XT/XTR/XO/XX bits.