fitting new rear shock on fantom ds frame (hardware issue)

[tj90]

I got a new rear shock ('09 monarch) and it has a different lower eyelet diameter (1/2" versus 12 mm Ario that came with the bike). I got a new rock shox eyelet hardware kit. The stock RS spacer kit has a slightly larger inner diameter. Now the lower motobecane pivot bolt has play. I measured the lower pivot bolt at 7.82mm diameter. I really need a lower pivot bolt that is truly 8 mm diameter.

Does anyone know if motobecane updated their lower pivot bolt? I would image that since rock shox updated their lower eyelet diameter to 1/2" on their '08-'09 shocks, motobecane or anyone updating their frame will need the new spacer kit and 8mm pivot bolt. Unfortunately, I cannot source a hollow hex pivot bolt from mcmaster, fastenal... I suspect they are available somewhere, but I dont have a source or know where to look...

[tj90]

I learned from the suspension forum that the diameter of the bolt is not that important. The bolt should compress the frame around the hollow axle so that there is no movement between the bolt and axle. I increased torque of the bolt and the slop was eliminated. I dont think I had enough bolt torque....

[romelman]

So I can just change my Ario shock with a monarch on my fantom comp ds? What size and specifications?

[CodyWy]

tj90, What do you torque your suspension bolts to?

[tj90]

From Joe at Bikes Direct:

Motobecane Fantom Full Suspension Bicycles

Lower Pivot Bolt (Near Bottom Bracket)
Apply Loctite 242 to the bolt, and tighten to 115 in/lbs
.
All other Bolts
Apply Loctite 242 to all other bolts and torque to 90-95 in/lbs
Check for smooth operation of the pivots and shock bushings. Ensure
that the shock reducers are not rotating on the shock axle - the shock
should be rotating on the reducers.

Pivot Axles
Make sure all the bolts are torqued to spec. using two allen wrenches
(one on each side if two sides are present).

Once the bolts are properly torqued, check the bearings for smooth
operation and side-side play

[tj90]

So I can just change my Ario shock with a monarch on my fantom comp ds? What size and specifications?

If the shock eyelet diameter is different, you will need rockshox hardware kit. My ario and monarchs are different...

[CodyWy]

Good info. Thanks.