Time for some feedback from the bike guys here....
Ever since buying my Fisher Paragon 3 years ago, I have noticed an annoying flex in the rear end when giving full-throttle to the pedals, and a distinct and related lack of zip when accelerating and doing short, steep aggressive climbs. It feels like the rear end is buckling and flexing under the torque. I don't like it, and it detracts from the fun of an otherwise great bike.
At first I thought it was the frame, as the rear triangle is not the best-engineered piece of alloy I have seen....there isn't even a cross brace at the top of the seat stays. But then I started looking at the wheels as the possible culprit. A quick note to Liam here confirmed that this was worth checking out, so I starting polling a bunch of bike shop techs for their opinion. All agreed that the Bontrager wheelset that came stock on the bike (Rhythm Comp) is not up to carrying the weight of a 220 lb rider. They have 28 spokes (lower than most), and those look pretty thin to me.
So the question is, what to do about it?
Replacing the wheels was my first thought, but this can be pricey, and the overall quality of the frame may not be worth it. I really like the bike, however. The handling is great -- it has about a 69 or 70 deg. HTA, which feels very natural -- not too twitchy, but still agile enough for tight trails. And the other components are good (Fox fork; SRAM X-9 drivetrain; Avid brakes). The least expensive aftermarket wheelset I could find was a WTB Laser Trail for about $350....pretty decent price. I looked at these in a shop and they are certainly more solid than my Bontragers -- thicker spokes, and 32 count. If I sell the Bontragers for, say $100 or so, net cost is reasonable. But reviews on the WTB Lasers seem to be mixed - some good, some very negative.
My concern is that the performance gain may only be marginal, and unless I buy a heavier all-mtn. wheel like a Haven, I may not notice much difference. FWIW, the Bontragers weigh about 1900 grams the set.
Re-spoking the Bontragers with burlier spokes is another option, and would certainly be economical, but then I am still limited to only a 28 spoke count. Is this a deal breaker right from the start, and the spoke count is just too low? Or can I make the wheel significantly stiffer just by using stronger spokes (bladed) even with only 28 spokes?
The stock wheels have held up very well, I must say. They have stayed very true, with only minor tweaks to the spokes to cure a tiny wobble or two.
I guess a more general question is, are all 29er wheels, when ridden by big guys like me, prone to this problem? I just don't have enough experience with different bikes and wheels to know.
Looking forward to some insight into this.
Thanks!
Svend