Building a Specialized Stumpjumper 96er Mountain Bike
The problem: We have a standard-issue Specialized Stumpjumper that has been passed over in favor of a Jamis 29er hardtail. The Stumpjumper needs a new life; and though the Jamis is a fun ride, we can’t help but think that the 29-inch rear wheel on it is too big. Swap-and-pedal experiments convince us we’re on the right track, so we move forward.
A quick phone call to a Specialized tech confirmed that what we were proposing wasn’t totally crazy, and also should work fine if we resist the urge to mount longer-travel forks. Easily done!
A search of Ebay for Rock Shox Recon 29er forks and a WTB 700c (29 inch) wheel finds us what we need. Click here to search Ebay and you’ll find a pile of both new and used 29er bicycle forks for sale. A few days later we have the parts in hand and the Stumpjumper goes up on the stand and we get to work. It was a simple 20 minute job, and here’s how we did it:
Pop the front wheel off the donor bicycle.
Bend down the locking tabs on the front rotor mounting bolts, and remove all the bolts with a Torx driver.
Install the rotor onto the new wheel hub, and put all the bolts in snugly. Be sure to use thread locking compound if the manufacturer specifies it is needed.
Check the specs for your brake/wheel/bike and find the correct torque value for the rotor bolts. Our system is a Shimano BR-M765 and it calls for 18-35 in lbs for each bolt.
Stake the lock washers down against the flats of the bolts with a punch and small hammer. Now the new wheel is ready to go.
Clip the ty-wraps holding the hydraulic line.
Remove the caliper bolts with a 5 mm hex wrench.
Remove the caliper and let it swing free.
We don’t want to lose the little rubber plug in the top cap….
Loosen the stem adjuster bolt.
Remove the bolt from the star-fangled nut.
Remove the bolt and the top cap. Keep track of how many and what size spacers exist on your steerer tube, this will become important later on.
Loosen the pinch bolts on the stem.
Hold the fork in place, and pull the stem off the steerer tube.
There may be another collection of spacers on the steerer tube. Remove them, and keep track of how many there are.
Remove the old forks by carefully pulling the stem out of the head tube. Get ’em cleaned up and ready for Ebay!
Our replacement forks had the same length steerer tube as our original forks. If you want to preserve the handlebar “feel” of your front end, this is highly advisable. We slipped the new forks right into the headset and prepared to tighten them into position.
Hold the forks from below, and put the spacers you removed in place. You can make up a slight difference in steerer tube length right here, by subtracting or adding spacer length as needed. Slide the stem in place when you have the spacers sorted out.
Put on the upper spacer and the cap.
Tighten the adjuster enough to roughly bring the steerer into adjustment, and snug the pinch bolts lightly.
Check the front end for play, and do the final headset adjustment. Tighten the pinch bolts on the stem and snug the adjuster in place.
Don’t forget the little rubber plug.
Mount the brake calipers up, with a drop of non-permanent thread locking compound on the bolt threads.
Snug the caliper bolts, but don’t tighten them fully.
Install the wheel, and lock down the quick-release with the wheel on the ground to be sure the hub is centered in the dropouts. Now is the time to adjust the alignment of the front brake caliper, according to the instructions available for your system.
Finished and ready to roll!