ET: Engine (Twin) Shock Absorber

Joe

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VOC Member
Hi Joe, "clutch judder" is often down to broken springs in the ESA. I should check that it's OK before you start on the clutch. Cheers, Stu.
Hi Sut,
what I am not happy about is when accelerating (motor torque) there is some little ratte synchrone to motor revs so I checked ESA and just found to my surpise that one of eight inner spings PD27 was completely MISSING !

Q1: Is it possible that a single inner spring missing out of 16 can cause a noticable effect?
Q2: or might this come from wear of sprocket ET60/1 and PD3/2 - see pictures?

thanks for feedback
Joe
 

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stu spalding

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Hi Joe,
It's unlikely that 1 missing spring will make a difference if the rest are ok, trying to diagnose primary drive problems at long range is very difficult as there are so many variables. Best of luck. Cheers, Stu.
 

Bill Thomas

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Just wondering if you have "pinking " ?, Ignition a bit too advanced ?.
If you have an old Magneto and the points are too wide, You could try closing them a touch ?,
To retard it a bit, Sounds like you are getting there. Cheers Bill.
 

oexing

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. . . . well, I´d say . . .typical. Looking at the wear in some places you could try three positions for optimal fits of lobes . Maybe you can find marks that correspond to marks on the other part. That would be the one of three options that was in use for last long mileages. But then I don´t have ideas about your observations on the road.

Vic
 

greg brillus

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rotate the crank back and forth to see if you can "Feel" any backlash.......It is possible the keyway in the crankshaft on the right side and the crank pinion has movement in it. This can cause quite bad low speed knocking sounds from the engine similar to a big end bearing gone, had this on a few engines now.
 

Bill Thomas

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I get more worried by the wear on the inside now they are getting old !.
If you put it together without the springs and see how much end float and rocking, You get and the alignment
for the chain.
I would put it back for another 100,000 miles !.
 

Gary Gittleson

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rotate the crank back and forth to see if you can "Feel" any backlash.......It is possible the keyway in the crankshaft on the right side and the crank pinion has movement in it.

I'm curious about this. You speak of the keyway on the "right side". That's the timing side. Is that what you mean?
My bike (D Rapide) has a bit of a knock on take off in first gear. I've been assuming it's a bit of piston slap but maybe it's what you're referring to.
Gary
 

oexing

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Now that would be another slap on that ESA, from me as you´d expect, once again: Could that knocking be from bashing the moving part of the ESA onto the end plate when all stroke of the ramps is used up - as is typical in this case and no amount of springs will prevent this ?

Vic
 

greg brillus

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Gary, with the timing cover removed and the bike on it's rear stand and in gear.......if you rotate the back wheel and watch the E 80 nut that secures the half time pinion.......you will observe the nut moving and the gear not so much.........this is movement in the keyway, and this can happen for various reasons. This back lash creates a noise in the engine mostly noticeable at low engine speed that sounds bad.........The first time it happened to me on the racer back in about 2015 or 16 and I thought for a moment that the big end had gone, i have found it on other road going Vin's since then........not common but still happens. On the ESA's well another common issue that can be ignored at the time, is the actual compression of the springs........this not being enough.......Either the cam sleeve of the face washer is incorrect (perhaps a mismatch of parts used) who knows, but i have found on many bikes that when the ESA nut is tightened, that the actual compression of the springs is not enough. This must cause the springs to compress too readily causing the cam to "Ramp up" too soon. This is probably a major contributor to Vic's complaints about the design. On some engines I actually cut a piece off the cam sleeve to allow the springs to compress more, but it also depends on which washer combo you are using against these springs as well.
 
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