961 Birthday

ntst8

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Valve guides are cast iron, no appreciable wear on them or the valve stems.
Rocker bushes - these were easily removed, and i am told could be reinserted with hand pressure :oops:. Must have been very close to the rockers turning on the bushes rather than the bushes turning on the spindles. Ollie is making new ones this week.
Throttle body - idle air intake plugged and ready to go.
 
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gortnipper

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Valve guides are cast iron, no appreciable wear on them or the valve stems.
Rocker bushes - these were easily removed, and i am told could be reinserted with hand pressure :oops:. Must have been very close to the rockers turning on the bushes rather than the bushes turning on the spindles. Ollie is making new ones this week.
Throttle body - idle air intake plugged and ready to go.
The Norton assembly line build legacy is unbroken.
 

ntst8

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Crankshaft trued and ready to refit.
Crank oiling - Richard 7's Oil Route guide covers it well but doesn't mention the small holes in the top of the crank centre plate (pic below) - these seem aimed to squirt the underside of the pistons.
Also the page 6 of the guide shows the side squirters - it seems that these align with the open side of the hollow big ends (the cap on the outside face can be seen below), and rotational forces then force the oil into the big ends with drainage out via the grooves arrowed in the guide.
Bearings are all marked Koyo Japan and look/feel to be in good nick, no plans to change those.

961 Birthday (122) piston oiler S.JPG
 

ntst8

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The engine is nicely thought out for dismantling in the frame, the crankcase split allows one section to remain in place.
Next step, re-assemble the jigsaw once the bits which are in transit get here.

961 2021 Birthday (110) empty cases S.JPG
 

cliffa

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Thanks for the continual updates and pics Iain, a valuable insight into the 961 engine. When you mentioned "We have now relieved the holes in the cases as in Richard7's guide" can you explain further please?
 

ntst8

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Thanks Cliffa.
The bolts which mount the crank centre plate to the crankcase have a plain shank, then a threaded portion. According to Richard-7 some bikes (including mine it turns out) in the 2013 - 2015 range suffer from the unthreaded portion of the bolt projecting through the plate so that when you torque the plate in the place the unthreaded shank is forcing its way into the threaded hole in the crankcase. This gives a torque reading without necessarily clamping the plate tightly. Drilling out the first few mm of the hole in the crankcase provides clearance to allow the bolts to be tightened correctly. There looks to be plenty length of thread left after the modification.
 

cliffa

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Thanks Cliffa.
The bolts which mount the crank centre plate to the crankcase have a plain shank, then a threaded portion. According to Richard-7 some bikes (including mine it turns out) in the 2013 - 2015 range suffer from the unthreaded portion of the bolt projecting through the plate so that when you torque the plate in the place the unthreaded shank is forcing its way into the threaded hole in the crankcase. This gives a torque reading without necessarily clamping the plate tightly. Drilling out the first few mm of the hole in the crankcase provides clearance to allow the bolts to be tightened correctly. There looks to be plenty length of thread left after the modification.
Ah, I see. Thanks for clarifying Iain.
 
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