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Existentialism-- Just a bloody good excuse to go riding...

Tuesday, September 11, 2012

its fork and f@^k

A new CSU spotting additional 10mm travel and a refined crown, some weird colored lowers with the fork's original 2010 cartridges. That's my rebuilt '2010' Vengeance HLR. 

Interesting?  But really this was a result of one woe after another in what was supposed to be a simple part replacement +  normal rebuild event. Well the bonus is I now have a somewhat "80% brand new" fork and learnt a few other things about fork maintenance.

Creaky CSU after 1+ yr of usage warrantied, no questions asked.

Stanchions not moving smooth after reinstalling-- initially thought it might be some vacuum... Troubleshooting the rebuild,  seems like the old lower's alignment is off. 

Yup its probably a little crude but free the uppers,  drop the axle and see if it goes through both legs of the lowers for the alignment check.

Apparently not and the fact that I could then twist it by hand until things align wasn't very reassuring.
Actually at that point I was mumbling to meself.. "Yea this is pretty much f^%ked". Leaves me wondering if the creak was really due to the fork uppers.....

Luckily somebody have spare lowers hanging around. Hell yea its good to have friends, save me more waiting time to order from the factory.. and this one probably meant to go with a  Specialized Status.

Well, here we go again.. *disassembly* >>> *assembly*  for probably the 50th bloody time within a week...

Yup, previously mentioned on how stiff and all the fork is ... so what could have happened?...  Given how the bike gets thrown when I bail plus a few really hard falls taken with the front bearing most of the brunt... I still say it is pretty strong after all my crash-test-dummy antics spanning from Singapore to Thailand in the past ~2 years. Wouldn't blame the design or manufacturer for the multiple bendosis state of the lowers.. 

Fate of the old lowers?...hmmm maybe some "light saber" stanchions in there and hang up in the bike room as functional art providing some extra lumens when wrenching.

Things noted...

The sealed cartridge damper can take between 70-85ml of fork fluid. Recommended factory oil change is 70-75 ml with 7.5wt oil. But last week Dirty had his paws all over the damper and put in 10wt filled to the max 85ml. The verdict now from compressing the fork is that its over damped and feeling rather progressive. That wouldnt be too much of a problem as intended build of bike would run great with a stiffer front.

But oil weight/ volume probably are affecting the rebound rate... too slow even when ramped to fastest setting. The reported squishing/cavitation as some users has mentioned is likely caused by the oil volume..if it isnt filled to the max then probably that's where it comes from as the damper rod is cycled.

Going by all things observed, less oil would probably means stroke action is likely more linear but starting stroke might need to add a little more low comp to offset. Ok all these just means more mucking around with the damper unit next time.

Frankly when the old oil was first poured, I didn't think it needed to be changed but of course one can't tell how much the oil would have degraded from just the eyeball-o-meter.

The fastest way to drop the number of max clicks ~15 of your hi-comp is to install the gold ano knob in reverse. Stupid me.. luckily no damage done to this rather delicate portion of the fork. Easily rectified once you realize what's the problem.

If some black plastic washer drops out along the way (~10mm diameter) seemingly out of nowhere -- fret not, check the 2 respective nuts (as pointed by red arrows in pic below) meant to tighten down and hold down each end of your fork.

In both, underside of the nuts has a  recess for this black spacer. Just press it back in. BTW a rebuild kit should come with these new spacers... these I think are meant to be replaced and seal the hole area on the bottom end of lowers to prevent fluids (~15-20ml) in the open bath from dripping out. My old ones looks ok -- so being cheap I'm saving the new ones for future rebuilds.

DON'T skim on the 15-20ml oil to be poured into the lowers. The fork is not going to work right without it (update on 4 Oct 2012)

1 comment:

  1. Could you share what coil color was inside the HLR from factory? Thanks.