Another one lives!

Ron L

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I see you are using a longer rear fender like the Ranger 750. Does it interfere with the short single seat?
 
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Hi Sixtyseven,

Really like the look of the high pipe hybrids. There are a few that turn up at local bike meets and I am always drawn to them.

On another tack it may be your luck day. I've had two AMC alloy chaincases in my garage for the last 40 years ......... why? Last year I gave the worst one away for someone to use as a spare but kept the better on. Inner all intact, sprocket 'cover' still intact and sliding clutch seal very tight and not butchered. Outer good condition but light corrosion. Overall length 17.25 inches, 44 cm.

If it is any use it's yours for the price of the UK postage. Send me your mobile number to 'accesnorton username' @hotmail.com and I'll get back.

Cheers

Graham
Southampton
 
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I see you are using a longer rear fender like the Ranger 750. Does it interfere with the short single seat?
The forward edge is cut so that it just overlaps the concave area in the oil tank. I think it had to be squeezed a little to fit. It’s not the original seat and the base did need some modification at the rear. Who knows what mods these bikes have had over the years!
 
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The forward edge is cut so that it just overlaps the concave area in the oil tank. I think it had to be squeezed a little to fit. It’s not the original seat and the base did need some modification at the rear. Who knows what mods these bikes have had over the years!
From what I understand one of the common 'mods' on the early high pipe P11 was either cutting off or welding on whatever was deemed necessary to fit a dual seat. I passed on one locally because two sections of square tube had been welded either side of the frame rails (that and commando pistons.. not for this boy)
 
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Hi Sixtyseven,

Really like the look of the high pipe hybrids. There are a few that turn up at local bike meets and I am always drawn to them.

On another tack it may be your luck day. I've had two AMC alloy chaincases in my garage for the last 40 years ......... why? Last year I gave the worst one away for someone to use as a spare but kept the better on. Inner all intact, sprocket 'cover' still intact and sliding clutch seal very tight and not butchered. Outer good condition but light corrosion. Overall length 17.25 inches, 44 cm.

If it is any use it's yours for the price of the UK postage. Send me your mobile number to 'accesnorton username' @hotmail.com and I'll get back.

Cheers

Graham
Southampton
Massive thanks for the super kind offer Graham, made my day! Just a shame it wasn’t quite the right part. The shows not over yet though, it’s looking like we’ll be up and running soon, post lockdown! ;)
 
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It's unusual to find one these days that still have the dished O.E.M. 7 1/2 : 1 pistons. Most of these survivors have had top end work and the dished pistons became hard to find in oversizes a long time ago.


From what I understand one of the common 'mods' on the early high pipe P11 was either cutting off or welding on whatever was deemed necessary to fit a dual seat. I passed on one locally because two sections of square tube had been welded either side of the frame rails (that and commando pistons.. not for this boy)
 
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It's unusual to find one these days that still have the dished O.E.M. 7 1/2 : 1 pistons. Most of these survivors have had top end work and the dished pistons became hard to find in oversizes a long time ago.
Mine came with new flat top pistons with the valve cut outs. They were standard sized but the bores were marked beyond honing out so went up to +20. It almost looked like it had been sat in water!

Would the flat top design of pistons have an effect on compression ratio?

Great avatar pic BTW! :cool:
 
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It's unusual to find one these days that still have the dished O.E.M. 7 1/2 : 1 pistons. Most of these survivors have had top end work and the dished pistons became hard to find in oversizes a long time ago.
Yes, I was fortunate that mine responded well to a de-glazing and new rings. Mind you, the aftermarket parts availability seems better now than it was 31 years ago :)
 

Ron L

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Mine came with new flat top pistons with the valve cut outs. They were standard sized but the bores were marked beyond honing out so went up to +20. It almost looked like it had been sat in water!

Would the flat top design of pistons have an effect on compression ratio?
Very definitely. Atlas/P11 dished style pistons gave 7.5:1 CR while Commando pistons give 9:1 CR. Your flat top pistons with valve reliefs sound like 750 Commando pistons.
 
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Very definitely. Atlas/P11 dished style pistons gave 7.5:1 CR while Commando pistons give 9:1 CR. Your flat top pistons with valve reliefs sound like 750 Commando pistons.
Thanks for the input. It certainly feels lively, even at running in revs!
 
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Got the old girl back from quarantine this week. Sunny afternoon so we had to nip out for an essential trip! The bikes running lovely. Running in so keeping the revs sensible but that torque makes it still feel lively. It’s not completely housetrained yet but we’re still working on that. Is there such a thing as a finished classic bike?!

 
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Your bike is beautiful , you have done a remarkable job with what it sounds you started ! Kudos to you from east coast of Canada !
Thank you Craig! She’s still not quite there but almost. I’ve told myself it’s worth all the effort and cost to save another of a rare breed! Just as long as my wife doesn’t find the receipts! :oops:;)
 
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Looks good.

Do you have plans to put any miles on it?

Might want to get some rubber on the foot pegs before taking it too far out of the driveway. They do vibrate through the entire chassis a little. ;)

Oh yeah, you said window maker. Ron Woods went over the Widow Maker hill climb in the USA, and held the number 1 plate for a while. No small feat!! He did it on a Norton modified for hill climbing. He was an accomplished rider, tuner, and fabricator.
 
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