Yes this is what I've suggested as best path forward. I have sent him a list of recommended parts from AN (gasket, seals, gear pedal shaft bushing, tabbed washers for stator, shake proof washer for rotor nut) and a link to the Aliexpress sprag.After the Norvil sprag let go I called them thinking there might be a warranty period and that it might be greater than 24 hours.
That turned out to be wishful thinking as Les informed me that all of the components must be replaced every time or failure will definitely occur.
I recall that the sprag alone was just under $200 cdn landed here and the other parts were about 6 or 700. I decided it would be better to kick start the thing that spend another grand on something that might let go in hours.
Not long after that someone posted that they had replaced the entire gubbins with the new Norvil items and the sprag still let go in a very short time.
So I decided to forget the estart for a few years.
At some point Matt at CNW mentioned that they were looking at making uprated drive parts for the MK3.
I would have gladly gone for those items however it took awhile for them to become available.
In the meantime I noticed the cheap Sprags on AliExpress and thought it worth a try for such a small sum. My inner and outer drive surfaces on the original parts were pretty beat up, but still measured ok. So cheap sprag and old beat up parts that "must be replaced with the sprag " are still working well.
If that hadn't worked I would have installed the CNW items, and still might at some point.
If your friend doesn't mind wrenching, I would try the cheap sprag in there without changing anything else.
If that doesn't work, get the CNW stuff.
Glen
Mine x 2, Ali express Sprags did not "let go" but the ends of the dogbones flattened out and the sprag failed to grip on the inside of the engine sprocket. Prior to this it should be noted I had the inside of the engine sprocket machined out and a hardened bearing race/sleeve fitted and machined to spec. When the sprag failed all it did then was make a whirring sound as spun round not turning the engine over. I have since stumped up for the CNW MK3 Starter kit.Although initialy it was great but twice recently it has slipped when on a cold start it did then start,but hot is perfect,just need to touch the button and the engine bursts into life.Just throwing this out.
Has anyone here or heard of an Ali Express sprag letting go?
Those parts form the anti-backfire device, which I gather helps protect starter drive from shock load if backfire occurs while operating.I had Mark 3 20+ years ago. Didn't have any sprag problem as the motor was to week to spin it cold.
So I took the starter and little gear off, blanked it out and rode.
Left all the other paraphanelia in there. Always though it was complicated.
Put the starter back on when I sold it so he could have it.
Two questions.
1. Parts 7,8,11,and 12. What is there purpose? Some kind of shock absorbtion?
2. After replacing all the parts in the plunger assembly, I still had the off idle primary cackle.
To fix/minimize it, I turned the idle up. I often wondered if a new Primary chain would have solved it.
The bike did have 25k miles on it. Would a chain have fixed it, or this is a normal condition?
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Yes, I fought it. I believe I eventually had it right. Who knows, 20 years ago.Those parts form the anti-backfire device, which I gather helps protect starter drive from shock load if backfire occurs while operating.
By plunger, I assume you mean the hydraulic chain tensioner? I was studying a mk3 primary chain case rebuild video and the guy mentioned a common mistake is to place the "plunger" spring plastic end caps the wrong way around. The longer, smaller diameter end can slide inside the spring so that is what some people do. Correct fitment is long smaller diameter end point down the bore away from the spring. Getting that wrong means no chain tension and a constant clatter. Also, the tiny holes in the plastic caps, the pistons and housing bores all need to be free flowing. The check valve ball bearing needs to be free to rattle when cleaned out.
good sleuthing!So I was back at the mk3 bike today to fit the new Ali express sprag.Eventually got it all in there ok. Lots of time went by messing with a badly worn shifter bush in outer cover. Turned out cover had been welded to repair a crack horizontally rearward from the shifter opening. A very big, ugly donut of weld inside around the opening,and a big steel washer stuck/welded? to the blob to support the bronze bushing. Seemed like Bush worn on the shaft, sloppy, but also able to spin in the cover hole, so likely worn there too. New bushing fit both cover and shaft much better, but not full held in cover. As there an oil drainage hole in bush to align to hole in welded blob, decided to secure new bushing with some
Locktite against cover hole side.
So after everything back on except outer cover, we tested the starter....SAME BLOODY WHIRRING BUT NOT TURNING ANYTHING!
Starting to think someing else wrong inside starter...but then I asked again. Is battery charged? He has told me earlier new battery (3-4months) and he charged and rode a half dozen times before no cranking issue. Ok so I asked to see charger...well turns out it was a booster starter, not an actual charger! Tested battery volts, 9.2v!!!
Attached booster, and everything spun up nicely as expected. So looks like his battery was original problem. Not sprag. Told him to get a real charger to try to recover battery. Told him how to confirm rec is rectifying and zener's are holding max volts to under 15.5v.
We'll see what happens...
Well, not so great....seems my assumptions "made an Ass out of U and Me" as the saying goes ;-)good sleuthing!
Switch is on bottom of gearbox
Thx. Will investigate. First check will be for blown bulb or bad connection.Switch is on bottom of gearbox…06-5390…fits through the gearbox to a “button” on the camplate …maybe out of adjustment. It does not effect the starter engagement
Rod