Bicycle Mechanics - Trek Navigator 2.0 rear axle

Looking to buy a Nav 2.0...I am told I am too heavy for the 'free-wheeling' rear axle (250 lbs) and that I should upgrade to the 3.0 since it has a 'cassete'-type rear axle and will support my weight....Am I being 'upgraded' by a salesperson needlessly?

I just looked at Trek's web site and they say the rear is a cassette, not a freewheel. If that's the case the seven would be OK.
You would be too heavy for a freewheel because the right side bearing is inboard near the hub flange. The axle is unsupported out to the dropout and prone to bending and breakage.

Thanks so: Cassette:Shimano 14-34, 7 speed
means the Shimano 14-34, 7 speed is NOT free wheeling? Sorry if I sound ignorant, because I am....

At 250lbs, you need strong wheels. You won't find them on a 2.0. The cassette wheels allows for better support of the axle so it won't bend. It looks like, from the website description that the rim is a double wall on the 3.0 which, as far as I am concerned, is a must for a heavier rider. Freewheel type hubs often have bent axles due to the amount of unsupported axle that sticks out from under the freewheel. A salesperson told you that? Sounds more like a mechanic to me. Good advice either way....

EDIT: davidad is wrong about the spec. "Cassette" is a default description on the site. They use it everywhere, even on single speed cruisers! He's right about everything else, though! That bike has a Shimano TZ31 7-speed 14-34 freewheel (http://www.bicyclebuys.com/drivetrain/Cassettes/1010031/goog). The 3.0 is the only cassette-equipped Navigator.

Thanks...looks like a 3.0 for me....is the 2.0 okay for my 130 lb wife? Other components good?

Yes, no argument that a cassette wheel will be stronger. But for other 250 pounders reading this, don't assume that a freewheel bike is out of the question. I do believe people of that weight and more rode bikes before cassettes existed!

I do believe people of that weight and more rode bikes before cassettes existed!

They sure did.....but......axle spacing at the time was mostly 120 or maybe 126, and most decent hubs had chromoly axles, which means that not only were axles shorter, they were also stronger. Now we have 135mm spacing and the lower quality axles (which are hollow due to the QR) bend much more easily.

Nav 2.0 sounds fine for your wife given her weight.

Let us know how things turn out.

The Navigator 2.0 has a freewheel. The Navigator 3.0 has a cassette.

Shimano never made a 14-34 cassette with MegaRange. The MegaRange cassette is 11-34.
Any cluster with an 11 or 12 tooth cog is a cassette.

You might want to take this discussion to the Clydesdale forum.

I was 290 and riding a single wall rim with freewheel and had no issue for 2 years at 90 miles a week. Get the spokes tensioned properly, avoid potholes and curbs and you should be ok.

Im no bike mechanic but last year in Aug I bought a new Trek Navigator 2.0, at that time I weighed 318lbs, I bought the bike to lose weight. I started out riding the bike 4 miles per day, and worked my way up to 12 miles per day until the middle of Nov, after my lap band surjury last Feb I again started riding the bike in early April 12 miles per day, I road the bike six days a week until the end of June, when I got down to 240lbs I bought a road bike. My Trek has been a good solid bike the only issues I've had with the Trek is from last year, I broke one spoke, and the wheel needed trueing once, other than that I've had NO problems what so ever with my Trek Navigator 2.0.
Paul

..I bought a new Trek Navigator 2.0, at that time I weighed 318lbs,....the only issues I've had with the Trek is from last year, I broke one spoke, and the wheel needed trueing once, ...

But we're not dealing with absolutes here, we're playing the odds. Freewheel hubs do put more strain on the axle, there's no doubt about that.
But even if the margins to failure are smaller doesn't mean that failure is guaranteed.
Riders who are lucky, careful and good at going light can get away with a lot of things that other riders(of the same or lesser weight) will get in trouble by.