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"A local bike-shop bought that 650cc racer with the blown engine from Ed and they were pissed because there were no racing parts in the engine, Ed had just blueprinted the engine and modified the stock parts so they worked much better, he also did lots of testing at the drag-strip to get the exhaust and intake-tract length optimized which he said made a big difference in power."

This isn't a surprise at all. Back in period there wasn't much available unlike today.

Most of the period race engines that are road / production based used modified internals. The Norton twins' weak point was conrods and crank but by 1961 Norton start fitting nodular iron cranks (spherical graphite) to it sports bikes 88ss, 99ss and 650ss, also other AMC twins like Matchless and AJS CSR twins too. This pretty much sorted the crank braking issues. Rods were still suspect however so were regularly changed but always balanced and polished.

Nimonic steel valves were a usual mod (factory race kit and available to buy) much stronger than standard and perfect fitted valve spring length by shimming under the lower cup. There wasn't a huge amount you could do regarding camming either, as wide-ish valve angles made radical timing almost impossible without pocketing valves / pistons and loosing compression. As for race pistons? There was virtually nothing available so standard high compression SS pistons with a head skim either 20, 40, 60 thou to raise the ration a little more was also normal. But even standard high comp 650ss pistons are a difficult find today. Its fair to say that most internal engine mods were about reliability and not purely seeking peak horsepower. Utilisation of inlet and exhaust pulse was were most radical work was done by factory and home tuner (if they had the money).

Interestingly Triumphs Thruxton T120 bikes from 65 (factory specials) were quite standard except for cams and followers, 40 or 60 thou head skim, a good port shape and 1 3/16 monoblocs, with stepped down small bore header pipes (with balance) all good for 135mph with a fairing. Likewise AJS and matchless factory prepared racers were similarly prepared. Or rather nothing special. I have owned a genuine Triumph Thruxton Bonneville from 65 and AJS Model 31 CSR Thruxton from 61.

I guess when thinking about some of these older bikes you have to set aside modern ideas and think "period".

If the bike is looking for a new home, it can come over this side of the pond and live in my workshop and in the company of Manx's, race Domi's and even the odd XRTT after a little sympathetic and gentle preservation.
 

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The magneto is one sold by Joe Hunt at one time. I have the same mag that used to be on a Norton race-bike. The only difference on my mag is the finned cover actually says "Joe Hunt" on it, probably just an earlier or later run of castings. I e-mailed Hunt about it a number of years ago and they did not have much to say about it except that if I wanted replacement parts for it that they would have to see the mag or good photos of it's points etc. before they could tell me if they could supply them.
If it turns out that you need points and Joe Hunt can't supply them, then let me know. I seem to have a collection of NOS points and may be able to match something up.
If that mag was built in the USA, there is a slight chance I have something that would work as is or could be modified to work. Or as in the dark ages, maybe you could replace the points (see top left of photo) in the points if the rubbing block is still serviceable.

Points.jpg

Jalsteve.... I have a box of oddball British pistons too. Some prewar. Chances are slim, but you never know....

Pistons.jpg
 

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by 1961 Norton start fitting nodular iron cranks (spherical graphite) to it sports bikes 88ss, 99ss and 650ss,
Wrong. Norton cranks were always forged steel with a cast-iron central flywheel. Being an SS made no difference at all, the same cranks were used in all the bikes across the board. For 1961 the 88/99 cranks were made stronger by making the internal sludge-trap smaller diameter, thus increasing the thickness of the rod-journal wall. Triumph bikes also had steel cranks with iron flywheels. It was Matchless that had the all-iron one-piece crank which switched to nodular iron about 1961.

There wasn't a huge amount you could do regarding camming either, as wide-ish valve angles made radical timing almost impossible without pocketing valves / pistons and loosing compression. As for race pistons? There was virtually nothing available so standard high compression SS pistons with a head skim either 20, 40, 60 thou to raise the ration a little more was also normal. But even standard high comp 650ss pistons are a difficult find today. Utilisation of inlet and exhaust pulse was were most radical work was done by factory and home tuner (if they had the money).
Anyone should know the Norton twin had a narrow valve angle compared to the BSA or Triumph pre-unit twins, so would have less problems with cam timing and high compression, and anyone should know the 650ss got 9:1 compression with a flat-top piston while the Trumph and BSA 650s needed domes for the same ratio. The 650ss did not have any higher compression pistons than any other 650cc Norton twin, but there was a domed piston for the 99 that was sold by Norton starting in the late 1950s that was an option, and people put those into 650cc bikes sometimes after shaping the skirt for the larger 650 flywheel. Ed Bilton-Smith had the backside of his standard 650 camshaft ground to a smaller radius and he did not have to "pocket the valves". Any competent mechanic checks valve-piston clearance, so that point is moot. Taking advantage of intake and exhaust pulse cost the least of any engine modification as all it entails is making the exhaust pipes or intake manifolds longer or shorter, very easily and cheaply done.

The lesson is that the person who does the most talking might not know the most, but just enjoys hearing themselves talk the most.......
 

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Wrong. Norton cranks were always forged steel with a cast-iron central flywheel. Being an SS made no difference at all, the same cranks were used in all the bikes across the board. For 1961 the 88/99 cranks were made stronger by making the internal sludge-trap smaller diameter, thus increasing the thickness of the rod-journal wall. Triumph bikes also had steel cranks with iron flywheels. It was Matchless that had the all-iron one-piece crank which switched to nodular iron about 1961.



Anyone should know the Norton twin had a narrow valve angle compared to the BSA or Triumph pre-unit twins, so would have less problems with cam timing and high compression, and anyone should know the 650ss got 9:1 compression with a flat-top piston while the Trumph and BSA 650s needed domes for the same ratio. The 650ss did not have any higher compression pistons than any other 650cc Norton twin, but there was a domed piston for the 99 that was sold by Norton starting in the late 1950s that was an option, and people put those into 650cc bikes sometimes after shaping the skirt for the larger 650 flywheel. Ed Bilton-Smith had the backside of his standard 650 camshaft ground to a smaller radius and he did not have to "pocket the valves". Any competent mechanic checks valve-piston clearance, so that point is moot. Taking advantage of intake and exhaust pulse cost the least of any engine modification as all it entails is making the exhaust pipes or intake manifolds longer or shorter, very easily and cheaply done.

The lesson is that the person who does the most talking might not know the most, but just enjoys hearing themselves talk the most.......
That was pretty much of a dick reply. Are you as big of a know-it-all dick in real life as you come across on here? SO far you have made 2 posts and managed to deliberately call out and insult 2 of the regulars on here. Paul and Jalsteve have both been on here a while and have shared lots with the members on here. I think they both have established credentials via work ending up in publications and on racetracks. Just who are you, what have you done and why should I care?

Your attitude sucks. I hope you come across better in person.

Have a sparkly day,
 

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Wrong. Norton cranks were always forged steel with a cast-iron central flywheel. Being an SS made no difference at all, the same cranks were used in all the bikes across the board. For 1961 the 88/99 cranks were made stronger by making the internal sludge-trap smaller diameter, thus increasing the thickness of the rod-journal wall. Triumph bikes also had steel cranks with iron flywheels. It was Matchless that had the all-iron one-piece crank which switched to nodular iron about 1961.



Anyone should know the Norton twin had a narrow valve angle compared to the BSA or Triumph pre-unit twins, so would have less problems with cam timing and high compression, and anyone should know the 650ss got 9:1 compression with a flat-top piston while the Trumph and BSA 650s needed domes for the same ratio. The 650ss did not have any higher compression pistons than any other 650cc Norton twin, but there was a domed piston for the 99 that was sold by Norton starting in the late 1950s that was an option, and people put those into 650cc bikes sometimes after shaping the skirt for the larger 650 flywheel. Ed Bilton-Smith had the backside of his standard 650 camshaft ground to a smaller radius and he did not have to "pocket the valves". Any competent mechanic checks valve-piston clearance, so that point is moot. Taking advantage of intake and exhaust pulse cost the least of any engine modification as all it entails is making the exhaust pipes or intake manifolds longer or shorter, very easily and cheaply done.

The lesson is that the person who does the most talking might not know the most, but just enjoys hearing themselves talk the most.......
I usually can't be arsed with shit like this.

A few facts here - Yes Norton twin cranks are forged but there was indeed a material change in Norton cranks around 1960, Norton published a bulletin in one off the weekly mags either Motorcycling or The Motorcycle. Norton cranks broke when pushed hard so did Triumph, AJS and Matchless just broke!!! But the same material was adopted by AJS and Matchless to cure their crank failure issues in from 1961 (works and TT marshals bikes got the stronger crank in earlier). I don't think Triumph ever changed they seemed to snap in the same place on unit T120 and T140!

Speaking of valve angles - everything is relative and I said "ish" referring to Norton, I wasn't comparing to Triumph or BSA you did that. Its a simple fact that engines from this period had little scope for generating big rear wheel HP increases over standard, stepping from mid 40's to mid 50's or perhaps a little more was about as much as you could get from a 650 unless grenades are your thing. Reducing cam base circles or altering follower radius are minor mods on standard kit which was normal stuff to do but that's hardly radical is it. Neither are raised dome Domi pistons. To reiterate my point there was little available so you worked with what you had or could get. If you would take the time to read what I wrote you might feel less inclined to shoot from the hip. I have built more "proper" race engines than I care to remember from 4 stroke GP singles and twins to 2 stroke multis and have a good knowledge of the fitting process. Stepping from a engine like a Manx in which much can be altered to a road pepped parallel twin is bit like getting off a thoroughbred and jumping an a cart horse so I can be a little dismissive or understate the work required to make a pushrod engine go well. And for God sakes don't mention the Norton domiracer....

Surprisingly I have never had a well sorted 99 / 650 make more power than a sorted unit T120 with its wide valve angles and high domed pistons - I have built quite a few of both. In fact the 31CSR I had with a head skim, sports cams and single carb would leave a 650ss for dead and pulled a healthy 126mph at Snetterton.

What are you building at the moment?

View attachment 91354

Look we are both knowledgeable guys and with prostate permitting we can have a pissing competition but you can stuff the "but just enjoys hearing themselves talk the most" last word freak thing straight back up your arse.
 

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I usually can't be arsed with shit like this.

A few facts here - Yes Norton twin cranks are forged but there was indeed a material change in Norton cranks around 1960, Norton published a bulletin in one off the weekly mags either Motorcycling or The Motorcycle. Norton cranks broke when pushed hard so did Triumph, AJS and Matchless just broke!!! But the same material was adopted by AJS and Matchless to cure their crank failure issues in from 1961 (works and TT marshals bikes got the stronger crank in earlier). I don't think Triumph ever changed they seemed to snap in the same place on unit T120 and T140!

Speaking of valve angles - everything is relative and I said "ish" referring to Norton, I wasn't comparing to Triumph or BSA you did that. Its a simple fact that engines from this period had little scope for generating big rear wheel HP increases over standard, stepping from mid 40's to mid 50's or perhaps a little more was about as much as you could get from a 650 unless grenades are your thing. Reducing cam base circles or altering follower radius are minor mods on standard kit which was normal stuff to do but that's hardly radical is it. Neither are raised dome Domi pistons. To reiterate my point there was little available so you worked with what you had or could get. If you would take the time to read what I wrote you might feel less inclined to shoot from the hip. I have built more "proper" race engines than I care to remember from 4 stroke GP singles and twins to 2 stroke multis and have a good knowledge of the fitting process. Stepping from a engine like a Manx in which much can be altered to a road pepped parallel twin is bit like getting off a thoroughbred and jumping an a cart horse so I can be a little dismissive or understate the work required to make a pushrod engine go well. And for God sakes don't mention the Norton domiracer....

Surprisingly I have never had a well sorted 99 / 650 make more power than a sorted unit T120 with its wide valve angles and high domed pistons - I have built quite a few of both. In fact the 31CSR I had with a head skim, sports cams and single carb would leave a 650ss for dead and pulled a healthy 126mph at Snetterton.

What are you building at the moment?

View attachment 91354

Look we are both knowledgeable guys and with prostate permitting we can have a pissing competition but you can stuff the "but just enjoys hearing themselves talk the most" last word freak thing straight back up your arse.
on a side note do you use any slick coatings on parts that can benefit from it ?ie piston skirt thrust faces,cam lobes,non rolling element lifter faces etc ?i started using
it in 1980 orv so when a friend of mine multi-time national champion sidecar racer larry coleman, who was sponsored by kal-gard, introduced it to us...
my experience esp on 2 stroke pistons is that it is/was quite beneficial
on my own race bikes ,air-cooled jobs, kawasaki and rotax

coleman piloting the number one
coleman.jpg

 

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Your cams should be marked, if not you'll need to measure lift and duration but figures can vary due to wear and tear or just buy a new set to be sure. Vernier cams work well for perfect timing you can also alter timing to suit riding style or conditions. Goldies are notorious for not starting hot or cold. I have found that induction is lazy and the plug is often a dry as a bone despite carb/float flooding and kick priming. Remember cam form is a combination of cam, follower and rocker ratio.

Most British gearboxes are car like.
once i dropped the cr down to a sane level for my use ,just cruising around here on public roads..once that was sorted it has never given me any starting issues
i can almost always get it fired up first kick hot or cold
of course my starting prep and procedure are perfection but only because over the years i have always had enough interest to read and memorise every bit of information from qualified sources about how to do it ecactly thev way it must be done
i think the word kick, is what throws a lot off on how to get a good spin going
besides of course having the crank in position, kicking, lol at the pedal is of no use
the lever needs be positioned as high as possible in its stroke with a good solid sector engagement
then its down to being coordinated enough to get body weight launched up by pushing up off the left peg
then as you come back down the right leg is extended
this gives a smooth long powerful stroke every time
it is the only way to get good crankshaft spin/inertia right on thru ex stroke and back down into intake stroke/comp stroke
my mag must have good maggots innit
i put in new points,gapped correctly and cigartette paper timed full pull on advancer to be the recomended degrees before tdc ,cant even remember what that was but
at full retard it idles slower than i would have thought possible
a few trial aned error sessions gave me a short range of advancer lever positions to clock to when starting
and the lever fully released gives max advance position according to my information
i've been careful to not ever get greedy on the advancer,during starting ,that is never think it needs more advance to start .. i hate it when shit kicks back
when hot i always give it a few gentle clean out spins with wot and decompression lever fully engaged and the sprk fully retarded
i think that is the key to a hot start as fresh cool as possoble charge

i fantasize of a compressed gas (i would use dry nitrogen of course) nitrogen starting system for it
learning to start the huge single cylinder ajax nat gas compressor units is what has gotten me thinking of this
of course incorecctly designed and applied could lead to scrap metal ,but i do want to build it just for kicks lol
it will absolutely work ,way betterb than we can imagine
a cam drive operated switching valve would only allow the starting gas tom be introduced for a very specific short time ,as in 45 degrees or more past tdc on the power stroke then shutting it off i dunno somewhere shy of bdc
a small very high pressure gas bottle would be be needed on the bike then a small secondary chamber to supply a limited volume at whatever pressure is ,from testing,determined to be ideal
the seconday chamber and its ability to be recharged with only limited volume is a safety deal
the cam operated switching valve will fully discharge the starting chamber to atmosphere as soon as it shuts off the incoming charge
and the starting gas charge is going to be introduced into the comb chamber thru a one shot decompression valve

this way the comb chamber is automatically sealed from the starting system plumbing upon fire
lol its not a race mod strickly for fun and the design exercise will get all kinds of heads spinning
you might laugh but the design is 100% viable it has been in use for over 100 years !!
the system will be much lighter and less obtrusive than e starting
it could be built cvompetely hidden from casual view
- - - Updated - - -

Your cams should be marked, if not you'll need to measure lift and duration but figures can vary due to wear and tear or just buy a new set to be sure. Vernier cams work well for perfect timing you can also alter timing to suit riding style or conditions. Goldies are notorious for not starting hot or cold. I have found that induction is lazy and the plug is often a dry as a bone despite carb/float flooding and kick priming. Remember cam form is a combination of cam, follower and rocker ratio.

Most British gearboxes are car like.
yep and harley pretty much everything was at one time a lay shaft type with input and output coaxial
 

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Just fit a Coffman starter. It worked for Jimmy Stewart, so it should work for you. I just generally bump start my 500 single race bikes, except the Ascot, I kept the electric starter on it and it even has stock compression. Bump starting a 12.5:1 500 single with slicks on grass takes some experience and skill. I got pretty good at it.
 

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on a side note do you use any slick coatings on parts that can benefit from it ?ie piston skirt thrust faces,cam lobes,non rolling element lifter faces etc ?i started using
it in 1980 orv so when a friend of mine multi-time national champion sidecar racer larry coleman, who was sponsored by kal-gard, introduced it to us...
my experience esp on 2 stroke pistons is that it is/was quite beneficial
on my own race bikes ,air-cooled jobs, kawasaki and rotax

coleman piloting the number one
View attachment 91442

Yes I use oil!

On new builds I use the oil intended for running in or if the engine is just stripped for a check I use the oil the engine has been running on. For general or race use shell bearing engines I use a full 3 ester synthetic, Miller in either 10-60 or 10-40. For running in I use a mineral on steel liners or manufactures recommendation for plated.

I use an assembly lube on plain bearing bottom ends for new assemblies.

For roller bearing race engines either Morris MLR40 or MLR30, I don't use Castrol R although a great oil it too expensive. For road engines a straight 30 or 40 mineral, although I have been using a semi 10-40 specialist classic oil recently again from Millar oils and its excellent (seals great on older engines). I have also used Amsoil monograde full synthetic on some Harley race engines which works well always with a big pump though.

Some guys still mix "R" with fuel as a 2 stroke premix or a little in fuel as an upper cylinder lube - use Castrol R for this DON'T use Morris MLR as its a synthetic blend of castor, detergents and anti corrosives and doesn't mix well with fuel. If using pump fuel in a 2 stroke I will use XR77 (full synthetic) or similar quality BUT if using Avgas / pump fuel mix I use a different oil Castrol a474. But we all our own preferences.

I don't use additives.
 

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indeed i to,feel, an oil film is the peak of loobricty ,rare as chicken lips in this digital age however
castor ,yessir i pay attention to frame geology,when sawapping out forks i keep a cloes eye on castor trails ,nothing worse than a customer complaining of soiled shorts from an ill engineered front end lashup that basivcally not mincing words
has reached spontaenious instability
additives? roger that never touch the stuff...... well i am a reminisint old fool not much hearing left but i can smell so so
admitedly i keep a few bottles of blendzall #485 around and use an oz or 2 per galion of gas in all my rides because the smell is so glorious and it turns heads whenever i fire up a heater \
just letting the idler fumes spread ,if someone looks over with a wry grin you know its brightened their day harkening
[h=2]#485 "Gold Label" Racing Castor/Power Booster[/h]
 

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Discussion Starter #52
Ok, I've been gone and busy the last three weeks with my first daughter getting married in N.J. Just got back home. I see I have some catching up and reading to do. I talked to the shipper on my way through Louisiana this morning, the Seeley gets dropped off in a fortnight then he's off to get the 650. I know it taking a long time but Chad has been moving bikes for me a long time and I dont have to worry about anything.
 
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