Trek Powerfly 4 & 5

Today I swapped out the stock 36 (steel) tooth chainring for a 38 Chainring (steel) on the PF4. Looking for a little better speed per gear. 4th-11mph, 5th-13mph, 6th-15mph, 7th-17mph these are max sustained cadence speeds. Most of the trail riding is 9-13mph and paved is 15-20mph. I am seeing about a 2 mph difference over the stock 36 tooth chainring. Next ride is this weekend.

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Starting about a month ago the rear hub started clicking. Took the PF4 into the dealer today and they confirmed the rear hub was bad and whole wheel will have to be replaced. Warranty covers replacement. That hub lasted about 4 months. They talked to me about washing the bike and how that may have contributed to the rear hub clicking. I have to believe that washing your bike with a garden hose is not the cause of a hub failure after 4 months.
 
Starting about a month ago the rear hub started clicking. Took the PF4 into the dealer today and they confirmed the rear hub was bad and whole wheel will have to be replaced. Warranty covers replacement. That hub lasted about 4 months. They talked to me about washing the bike and how that may have contributed to the rear hub clicking. I have to believe that washing your bike with a garden hose is not the cause of a hub failure after 4 months.
Get used to finding worn parts if you plan on riding with any frequency. My Powerfly 7 is heading into its 2nd round bearings and other 'consumables'
The good thing about these bikes is that you can DIY most maintenance, if you are handy and have a few crucial tools. Have fun!
 
Get used to finding worn parts if you plan on riding with any frequency. My Powerfly 7 is heading into its 2nd round bearings and other 'consumables'
The good thing about these bikes is that you can DIY most maintenance, if you are handy and have a few crucial tools. Have fun!
My wife has 18,000 km on her 2019 Powerfly 5 ...so far no problems in that hub area ,knock on wood...but yes I replace the chain ,cassette and front ring and brake pads frequently. The last time my sister in law took her Giant in for service the bill was around $600...ouch! I told her I will do it for her next time if she buys the parts. As Chromotose said if you get the tools you can do this routine maintenance yourself and save money. The Park tool instructional videos are great. I am far from a handyman so If I can do it then anybody with a modicum of strength can do it.
 
I hope you powerfly owners can help me validate your head angle. Can PF9 owners verify what their fork angle is?

I was checking the fork angle on the PF4 FS. Trek web site say 66.5 degrees head angle for all PS4 FS sizes which have 100mm forks.

PF4 FS: SR Suntour XCR 34, air spring, LO R damper, hydraulic lockout, tapered steerer, 41mm offset, oversized crown for eMTB, Boost110, 15mm bolt-on thru axle, 100mm travel
PF9 FS: SR Suntour Zeron 35, air spring, LO R damper, hydraulic lockout, tapered steerer, 44mm offset, Boost110, 15mm bolt-on thru axle, 120mm travel


I have replaced the 100mm Suntour fork with a 120mm Rockshox fork (44mm offset) so I expect it to be slacker. Trek is listing the Powerfly 9 FS which comes with a 120mm fork as 66.5 degrees head angle.


I measured the fork on my PF4 and it is 65 degrees which I expected with the longer travel. Every 20mm of fork length you gain about 1 degree slacker head angle.
I also went to a 27.5x2.6 tire which slackened the angle too.
 
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After a year the Powerfly 4 rear hub has had to be rebuilt for a second time. Water get's inside and the cassette bearings starts to rust. The hub makes grinding noises and starts to freeze up. Trek rebuilt the hub both times and it cost me $87. No more games this is BS. I had a set of DT Swiss XM481 with DT Swiss 350 hubs built. Switched the Specialized Purgatory tires for a set of Schwalbe Nobby NIC. Trek wheels and Purgetory tires are now on ebay.
Trek hub
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that sucks make me worry about my allant 8. they are Shimano hubs so I wonder what's going on? I love my dt swiss hubs.
 
I've gone through 3 Freehubs and many hub bearings. I've also snapped the inner axle and had one made (way better)
I bought a 'compatible' rear wheel only to discover that Trek fcuks you over by changing the measurement from the end of the end cap to the rotor mounts
19 mm as opposed to 'industry standard' 15 mm. Anyone need a rear wheel?
 
Hi,

I've been really happy with my powerfly fs4 but wanted some upgrades after awhile, so heres what I've upgraded to my powerfly fs4 so far:

Front suspension: rockshox 35 gold, 150mm
Rear suspension: rockshox sidluxe ultimate, 190x45
Brakes: Shimano SLX BR-M7120, 4 piston back and front
Rotors: Shimano sm-rt86, 203mm
Tyres: maxxis minion dhf 2,6"
Front light: LEZYNE ebike Macro Drive 1000
Pedals: bontrager color matching :D

Still left for upgrade:
Wheels: mavic e-deemax
Shifter: sram axs 1x12
Cassette: sram eagle axs compatible
 

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