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750 K2 Strip & Rebuild - help please
Lobo:
Thanks gents.
Nige, slightly struggling with your explanation/ logic as surely a torqued nut/bolt combination will behave as a ‘unit’, though I agree the fastener end planer forces will be higher at the floating end of the casting…
Maybe I’ve the wrong D washers, but certainly they provide no restrictions to the passage or siting of the bolt through the constant bore size….. as I mentioned; they’re currently rattling! (bolts tight but not checked wrt torque value yet)
Lobo:
Tips pls on compressing the rear shock springs wrt dismantling the units? Have looked eBay but concerned the jaws of all I see too bulky to engage the lower part of the spring (ie next to the damper)
Have tried 4x decent tie-wraps and ratcheting down… but too much force required methinks.
K2-K6:
--- Quote from: Lobo on July 26, 2022, 10:31:28 PM ---Thanks gents.
Nige, slightly struggling with your explanation/ logic as surely a torqued nut/bolt combination will behave as a ‘unit’, though I agree the fastener end planer forces will be higher at the floating end of the casting…
Maybe I’ve the wrong D washers, but certainly they provide no restrictions to the passage or siting of the bolt through the constant bore size….. as I mentioned; they’re currently rattling! (bolts tight but not checked wrt torque value yet)
--- End quote ---
;D I can understand struggle, my explanation was a bit rambling Simon. I know what I want to say but putting words to it more challenging.
Another go, essentially it's a compromise joint and so will have different views on deployment as I see it. Ideally the centre of the bolt "wants" to be dissecting the circumference of the fork stanchion to be a best design. Some do actually do that with a relief in the bolt that has to be placed in situ before the stanchion goes in to give correct load line with least possibility of distortion.
With the honda one here, as you tighten the bolt it wants to banana shape itself away from stanchion centre (pushing the bolt shank inwards toward the stanchion) which the D washer may help prevent. Also to stop the casting gap closing too much.
Guess they are trying to get workshop to do it up without snapping the casting as the stanchion is all but incompressable. If they've accommodated that with geometry in any way then it's advisable to assemble as the manual. If there's not a convincing reason to deviate then that would be wise.
Just checked an original fit 750 K2 and the D washers are definitely clamped tight when joint is secured.
Oddjob:
You may be vastly overstating this, Honda changed the design to a 7mm bolt and ditched the D washer. It appears they were trying to reduce the diameter of the bolt head to a 10mm instead of 12mm so that you couldn't tighten it as much thus breaking the casting. The castings didn't break at the bolt, they broke halfway round the casting, which would point to overtightening. The D washers I think were installed in the first place so that when they went rigid the bolt was tight enough.
Lobo:
Thanks Nige / Ken; I guess I’ll just stick with the parts manual drawings; if for no other reason than originality.
I’m away from the bike now for a couple of weeks; but do balk at doing the clampings up ‘D washer tight’: yesterday evening I went to my comfort limit wrt what I reckon a M8 Stanchion bolt in an alloy casting should take. (I did though pre-measure the D washers at 2.3mm thickness - maybe there’s an issue here?)
I’ll stick a torque wrench on it later and double check my wrist calibration…
Cheers!
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