Current production Norton 961 Parts

I will be getting some of these too from Ollie .

Current production Norton 961 Parts



Current production Norton 961 Parts
 
Tony,

I know that Ollie's rockers have better bushings, but what other advantages do they have over the stockers?
Care to revel price?
 
BritTwit said:
Tony,

I know that Ollie's rockers have better bushings, but what other advantages do they have over the stockers?
Care to revel price?
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Both the bushings and shafts are improved . The rockers are only 58 euro each , but then you must also pay for the fitting of his bushings and shafts . You can also take your machine down and send yours in . Rockers are OEM Norton .
 
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One of these days I will buy his bronze valve guides and have them fitted to my original head . He also does the valve seats , it's wonderful really. What is great about Ollie is that he is geared up for Norton 961's and no guesswork by him. Sending in parts will cause a long delay best do it winter time ? There are businesses here like (US Chrome) that specialze in Nikasil cylinders , bringing them back to original bore specs. Dirt bike and snowmobile cylinders is their bread and butter. This is what I want , I don't want press in steel liners.
 
Tony, I can’t be the only one who’s a bit confused as to what you’re doing!

You’ve already blue printed your engine, now you appear to be building another new top end.

You can’t seriously be going to all this expense and trouble just for 15ml of oil per 300 miles in your catch bottle surely ??

Are you just bored? Is your current engine faulty? Or ...
 
It may be worse than 15ml per 300 miles. But what is wrong with being proactive ? Besides , how do you expect to modify heads and ports and such without a spare ? I thought it was clear what I was doing - improving my 961 ... I am not hiding anything , my bike runs good. BUT , it's not as good as it should be. My head was not touched at Coote's just decabonized . I v'e already told you that my piston/bores have too much clearance , hence why the oil in airbox. We examined the rocker shafts that's all. I want a bike that runs as good as yours did ! :)
 
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TonyA said:
It may be worse than 15ml per 300 miles. But what is wrong with being proactive ? Besides , how do you expect to modify heads and ports and such without a spare ? I thought it was clear what I was doing - improving my 961 ... I am not hiding anything , my bike runs good. BUT , it's not as good as it should be. My head was not touched at Coote's just decabonized . I v'e already told you that my piston/bores have too much clearance , hence why the oil in airbox. We examined the rocker shafts that's all. I want a bike that runs as good as yours did ! :)
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Got it, well kinda.

What’s your thoughts on your piston to bore clearance issue? Unlikely to be wear isn’t it? These nickasil bores go on for ever!

Have you got a tuning plan yet, or is that something to play with later?
 
Bores were too big from new . They were outside the standard but inside the service limit (barely).
I can't remember now what the measurement was , but I know for sure it was outside the standard and just inside the service limit. Too many barrels were accepted that way and should have been sent back , as I now know.

Cylinder ID standard : 87.995mm - 88.005mm
Cylinder ID service limit : 88.050mm
 
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Tony if the cylinder bores and pistons are in good condition, round, true etc, then a little extra clearance can be taken up very effectively with modern piston coatings.

These boys did my JS pistons in my 920, they can apply up to 0.006” thickness! The idea is you have it done a tad too thick, the excess then burnishes off during breaking in leaving a perfect piston / bore fit:

 
Fast Eddie said:
Tony, I can’t be the only one who’s a bit confused as to what you’re doing!

You’ve already blue printed your engine, now you appear to be building another new top end.

You can’t seriously be going to all this expense and trouble just for 15ml of oil per 300 miles in your catch bottle surely ??

Are you just bored? Is your current engine faulty? Or ...
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I have to admit that I was also a " bit confused" at first until I realized that TonyA was just doing what TonyA has always done....trying to make his 961 the best it can be while spending his own money and then sharing the results with the rest of us. That is a stand up thing to do and I, for one, am most appreciative!
 
TonyA said:
Hello Voodoo , This was done to get to the bottom of my oil in air box issue . Lets use the 1oz. (30ml) per 1000 miles of riding as a minimum goal , and I will hope for better and I think that is achievable . My last test showed ~ (15 ml) in 300 miles at best . That is at a relatively steady 70 mph. As far as performance increase , if I get any I will take it . :)
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Why not gapless rings than?
 
Fast Eddie said:
Those parts all looks really nice. No signs of porosity etc, nice machining. Good to see.

I like the proper squish design of the bathtub combustion chamber. But I notice the step around the outside of the piston crown. That’s strange, it means that even if that step is gapped properly to the head to get a good squish, the rest of that squish area on the head is wasted. Ideally any recess in the piston should match the bathtub shape. Even more ideally, no recess is needed!

I’d look into what the CR would be with a flat top piston and a 0.040” gap. If you assume 1mm it makes it very easy to calculated the volume of that squish gap to add to the measured CCV to calculate CR.

As I’ve discovered on my 920 engine, a working squish allows a surprisingly high CR without issues. But you boys in the US who take long trips do have to factor in using low octane fuel when needed.
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Spot on!
 
TonyA said:
They're going in just as you see them .
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A gapless ring helps prevent blow by, and compression loss.
although I never used them on a motorcycle engine, I’ve used total seal gapless rings in all my car engine builds.
I would seriously consider using them since you’re installing a new top end. You said your goal was to get as little amount of oil in the catch can. Well here’s the answer.
 
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