It's a long way to 920 type(rary)

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Awesome custom Nortons to share/spread the grins of hard earned efforts. Agree 1st gear wisely done mildly til better hook up speed in 2nd before powering up. Food for the soul following this dream machine thread.

Kind of damaging to run Norton factory components like a hooligan but I'm looking forward to similar non Norton power unit upgrades to allow stunts on and off road and find pecking order against moderns on track days.
 
Yves' beauty, yesterday morning near Brussels:
It's a long way to 920 type(rary)


Another view, with my Featherbed 850cc racer in the foreground:

It's a long way to 920 type(rary)


This is yesterday's 'old pirates pack', Yves is center of the picture on the second row, right behind the Continental GT and I am second on his left, with the thumb up and a stupid grin on my face:

It's a long way to 920 type(rary)
Hi Bruno,
Better to say " the hugly old dwarf" in the center of the picture, I am only 1.70 meter high but the most important is that your feets touch the ground
And yes I am old: at my birdday the candels are more expensive as the cake...
 
Hi there, Here is wat I did to day:
Warm up the engine to drain the brake-in oil, change the oil filter, take the drain plug out and also the sump filter.
I clean the sump filter out and solder the circlip from the filter, no dirt found..
Tomorow more work to do on the bike
Keep you posted
Yves
 
Hi There,
Lot of work done to day:
Re- torque the head, I do it always the old fashion way: first lost the bolt 1/4 of a turn and then re- torque
After I made the valve clearence, two of the four need adjustement, If you wish to do the valve clearence exacly, it take time, I put 0.15 at the inlet and 0.20 at the exhaust.
Yesterday when I was warming up the engine, I find one oil drop falling from the higest cylinder fin on the tube from the RH exhaust, you must know that the RH tube on the Maney is passing in front of the cylinder and when the tube is hot a singel drop with oil make a lot of smoke....
You must know that I strip the whole engine if needed when I have one oil drop somewhere, so I start to search: the oil drop was hanging on the highest fin from the cylinder in the front of the engine, I take a magnificent and take a close look all around the head gasket, nothing to find, as dry as the Dead Valley.
The other indication I have is that the oil leak was not happening when riding the Seeley, only when warm-up the engine on the bench and here is wat I found:
The inlet rocker cover is hold in place by one stud and one bolt, my stud was damaged on the top tread and when I was tigening the bolt, the bolt was squeesing on the stud
and don't put enough pressure on the cover and is gasquet, so, when the engine hot there was a very small leak at the bottom of the cover and the oil found is way to the front passing true the middel of the head, I put a new stud and bolt and problem solved.
Keep you posted
Yves
 
As well as the later front disc brake works after some updating, that DLS looks so right! Beautiful bike, Yves, and don't stop writing about it.

Nathan
 
Hi Bruno,
Better to say " the hugly old dwarf" in the center of the picture, I am only 1.70 meter high but the most important is that your feets touch the ground
..

This reminds me of a fellow who married a woman who was much taller than he was.
When somebody asked her if it was uncomfortable for her, she said "Not at all; we meet perfectly in the middle." :p
 
Hi there
Here is wat I did to day: fill the oil tank with Redline oil, start the engine, warm it up and look for the oil drop from yesterday, no oil at the inlet rocker cover, and no oil in the front of the engine.
After 5 min. I kill the engine and take another look, searching for a oil drop, nothing....
But when the engine was cold I find a drop on the same fin, still coming from the middel of the head, to me it can be remains from oil from yesterday, at least I hope so...
I will clean the fin tomorow and warm up the engine again and see if the leak is finish
I make an appointment for the Dino on March 9, the man from the Dino is a Dutchman, Is name is Ruud Friedriechs, he have the records of my former runs, so we can compare. Ruud as also a analiser on his Dino, so I can adjust the carburation step by step, I have all the jets, needles and so on in stock for the Keihin FCR 35
At the moment I have 28 degrees advance, following the recomandations from Jim Schmidt, but maybe I can try 29 or 30, becouse the octane is higher here in Belgium as in California
Keep you posted
Yves
 
You got too much time on hand to have fun with, cool. Will be informative to all us on the ign timing dial in. Best fast burn chambers don't need as much sluggish high octane so 28' or even less may surprise power wise. A decent 920 with race oriented items/tuning should approach 100 crank hp @~7200 and almost as much torque so rear tire centers should wear to cords in 2500 if actually using it when not leaning much. Applying hi throttle only on far over leans extends 2500 mile center to almost 4000 miles of chain slack wearing delights. Someone got to do it for us rocking chair riders.

Fun way to know ya got it dialed in and pilot enough to enjoy it, smoke tire after light turns green into intersection to get rear swing out ~90' til facing new direction, let off to stop the swing around and instant rear re-hooks and jerks ya more upright nail a smoking non wheelie front floating leap out of there. Will remember this more than nailing your childhood sweetheart while devoted married to someone else. DAMHIK. If not up to this then ain't matched what was possible in 1968 with pure factory massaged Norton parts.

DO NOT FORGET TO DIAL IN CAM DEGREE FOR BEST POWER CURVE. I won bet against expensive race engine builder, Houston Texas, on my Chevy van V8 propane engine, after 4, $250 each dyno runs, to advance cam a final 0.5 degree/33.5, and $250 to retest, to suddenly put out more power than advertised could be fed by the carb installed. Wallet is main hp maker. Paid off in carrying 9 people mostly gals and cargo to leave jet ski's in our noisey wake waving and tossing beers at them in full upright hi wind resistance with 20 feet of flapping sun shade tarps overhead. Seriously discuss this with your dynometer guy.
 
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Hi there, the winter is back here, tons of salt on the roads, no ride at the moment, hope to do more kms before the Dino....
What I did to day:
The problem of the oil leak make me mad, so to day I wish to be sure that the oil drop I found yesterday was only remaining oil from the leak I found on the intake rocker cover.
I take brake cleaner and clean the whole head, with more atention to the air ways in the middel of the head
Blow the head dry and start the engine and warm up and watch the fomer place where the oil drop appear, even after 20 minutes, nothing!
My engine stay as dry as the pussy from Miss World when she looks at me!
The way to Tiperary is not long anymore and I will not be in the workshop the coming 3 days, I have a party at home with friends
and I must cook for 10 persons...
I will sleep well this night w/o nightmares where I sunk in oil...
Keep you posted
Yves
 
Keep that bike off of those roads until that salt has well and truly gone Yves !!
 
I've had head oil mystery i eventually traced to a fork seal leak blow back, ugh.
 
I've had head oil mystery i eventually traced to a fork seal leak blow back, ugh.
I have the same problem with my Codo fork before the Ceriani but this was easy to trace
Here in case of the 920, when riding the bike, the air flow keep the oil around the intake rocker cover, only when I warm up the engine the oil find is way to the front of the engine, In fact, the leak was so small that nobody would worry about, exept me...
Yves
 
Yves
I don't recommend more that 28 deg advance for high compression pistons. Its ok for low compression or short dyno runs - but not for extended WOT on the road or track. The higher compression or the smaller your combustion chamber - the less advance you need.
 
Yves, did you go for the dished pistons? And did you set the squish up to .050” or less? If so, then on top of what Jim has already said, a functioning squish band allows for some retard.

I’d be nervous about going over 28 degrees as Jim says. But I’d also be nervous about going very retarded, I’d only advice doing it in small steps, and on a dyno.

I accidentally set my ign quite retarded once, and discovered it was 10bhp down !
 
Yves, did you go for the dished pistons? And did you set the squish up to .050” or less? If so, then on top of what Jim has already said, a functioning squish band allows for some retard.

I’d be nervous about going over 28 degrees as Jim says. But I’d also be nervous about going very retarded, I’d only advice doing it in small steps, and on a dyno.

I accidentally set my ign quite retarded once, and discovered it was 10bhp down !
Hi Fast Eddy,
Yes I have dished pistons and I set the squish to 1.5mm, that must give arount 10.3 CR
 
Hi Yves,

Personally, I’d leave the ign at 28 degrees until it’s run in and you can play with it on the dyno. Whenever I’ve done this, I have found very little to be gained by moving a few degrees away from stock. With little advantage seen, and with the potential cost of failure of holed pistons etc, I’ve tended to keep it close to stock.

One small comment for next years rebuild: at 1.5mm (.060 inch) you are really on the edge of the squish band functioning IMHO. That’s the figure used by mass production passenger car engine OEMs. A blue printer would want it tighter than that.

With steel rods and your billet crank, I’d have gone for half that Yves.

In my Trident Hunter, with Jim’s steel rods but a stock crank, the tightest point of my squish was .032 and there was no evidence of piston to head interference when I stripped it.

In my 920, with its stiffer Maney crank and case, as well as Jim’s steel rods, I’ll be aiming for .025-.030.
 
Hi Yves,

Personally, I’d leave the ign at 28 degrees until it’s run in and you can play with it on the dyno. Whenever I’ve done this, I have found very little to be gained by moving a few degrees away from stock. With little advantage seen, and with the potential cost of failure of holed pistons etc, I’ve tended to keep it close to stock.

One small comment for next years rebuild: at 1.5mm (.060 inch) you are really on the edge of the squish band functioning IMHO. That’s the figure used by mass production passenger car engine OEMs. A blue printer would want it tighter than that.

With steel rods and your billet crank, I’d have gone for half that Yves.

In my Trident Hunter, with Jim’s steel rods but a stock crank, the tightest point of my squish was .032 and there was no evidence of piston to head interference when I stripped it.

In my 920, with its stiffer Maney crank and case, as well as Jim’s steel rods, I’ll be aiming for .025-.030.
Hi Nigel,
I will first go to the dyno, If needed I will lower the squish, in that case I need to tcheck the valve to piston clearance also
Yves
 
Surely that’s a job to look forward to for next winter Yves?

I’m pretty sure your valve to piston clearnece with the new JS2 will be fine, but, of course, you should check.
 
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