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RC4 Bushing question--- what material?

TrumbullHucker

trumbullruxer
Aug 29, 2005
2,214
591
shimsbury, ct
whats up guys

i have a sloppy pivot at my rebound side of my shock, the thrubolt is about 0.003" +/- 0.001" (shotty old digital caliper) undersize ( or the aluminum shock bushing is oversized, same dimensions )

i am planning on machining/ making my own. iv recently fell in love with cnc programming and machining ( its nice to take a break from welding time to time :p )

one guy at the shop recommended Delrin plastic.. machining this is incredibly easy; making the tolerances of the finished part tighter.. he says Delrin is used in bearings alot

Aluminum ( seems that like would be choice #1, but this is my third or fourth Aluminum bushing that i have had to replace, different downhill frames too)

or Stainless? but the bolts are stainless too and i have heard stainless rubbing against stainless is no good



and yes the O.D of the new bushing will be pressed into the shock

lets see what the ridemonkey shop says :thumb:
 

TrumbullHucker

trumbullruxer
Aug 29, 2005
2,214
591
shimsbury, ct
I'm not a machinist, or an engineer, but I used to fix things for a living, and nylon (delrin) bushings should be fine. Copiers used them to support high speed spinning shafts, and they worked fine.

my rear shock is protected by one of those mud gaurd/ rear fender type deals too, so not *alot* of dirt gets in there

i had brand new AL bushings the beginning of last season, and now i have this slop
 

GodSmack

Chimp
May 27, 2013
90
0
BC
Some RC4 shocks come with Igus (plastic) bushings. UHMD plastic is very easy to machine. Go for it .Make extras in case they wear out quickly.
 

GodSmack

Chimp
May 27, 2013
90
0
BC
If we are talking about the shock mounting eyelets. The bushing is a press fit oiled bronze bushing. The aluminum is nothing but spacers for the specific frame the shock is mounted to.
I have seen igus plastic bushings, bronze DU bushings.