Rear Shock Assembly for 914-6 - Boge Options

[DennisV]

I hate to belabor the rear shock topic, but I am stuck. I didn't have the original setup to reference, and I'm not finding much in terms of Boge details for 914-6.

• #6 Bump stop: Taper up or down? In the drawings and videos I’ve seen, it goes down. When I trial assemble, it seats much better into #8 cap when taper goes up.
• #5 Rubber stop washer: Does the side with grooves go up or down?
• #4 Cap - boge: Does the beveled side (i.e., smaller OD side) go up or down? Why does it even have a bevel?
• #4 Cap - boge: I assume it is meant to rest on the beveled edge of the strut shaft? When I trial assemble (without the spring) I doesn’t seem like there is enough length to get the #10 threaded bushing to start without some serious compression on #6 bump stop. Is this correct?
• #17 Washer: What is OD and thickness?

Thanks for any assistance.

[davep]

The PET diagram is not too bad if you look at the numbers.
1 the shock body
2 the lower perch retainer (not needed if the lower perch fts on the shock body)
3 lower spring perch
4 dust cap (stamped metal fits over the shock body like a bottle cap) I do not see #4 in the parts in your photos.
5 anti-siphon grooves down
6 bump stop rubber sits on the ledge at the top of the shaft
7 spring sits in bottom perch
8 spring cap
9 flat washer (large)
10 shaft nut (torque down to spec, applies preload to the spring which should not be loose
11 rubber bush fits over # 10 and centers the shock assembly into the bottom of shock tower
The shock assembly is now semi complete and can now be fitted to the chassis
12 rubber bush centers the shock assembly onto the top of shock tower (11 & 12 isolate the shaft from the body)
13 cupped washer (cup faces up)
14 self locking nut (new or excellent used)
15 dust cap

Your shock photos show a stepped washer on the step of the shaft. That is sort of where it goes, but it normally is bonded into the top of #6, and #'s 6, 5 & 4 are below it on the shaft.

When the shaft begins to bottom out #6 bump stop comes into action to soften the blow. When #6 compresses it will seal on #5 and the air inside is forced out. Later the shaft will extend, and #6 decompresses it will suck air into itself; if the grooves in #5 are facing down, then the grooves allow a path for air to reenter #6. If # 5 is not there to provide an air path, then the suction could extract shock oil past the seal on the top of the shaft and eventually ruin the shock.

When you install #10 you will have to compress the spring between perch 3 and cap 8.

The flat washer 17 you have on the pin appears to be about the correct size; it should cover the rubber bushing in the bottom of the shock.