Head flow testing.

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Thanks Jim will keep you posted on progress once I get back to the bikes in March.
Am looking at getting some internals off JS for one complete motor rebuild, so wil keep all your tech help in mind. Will end up with a really good reliable road bike for sure.
Regards mike
 
comnoz said:
That will not solve the cracking problem in an RH4 head. Fullauto cured that one. Jim
Click to expand...

Jim, what do you know about vacuum sealing a head and injecting epoxy? Kenny Dreer mentioned someone, Baisley I think, doing that...
 
I have not heard of vacuum sealing a head with epoxy although it could be possible .

There are vacuum sealing methods available using aerobic compounds and urathanes. I have done that in my shop.

The part is immersed in sealant and a deep vacuum is applied to the container to draw the air from the pores. When the vacuum is released the sealant fills the pores.

Usually this is most successful with a new part. Oil in the pores contaminates the sealants.

It is standard practice in some types of aluminum casting.
 
comnoz said:
It takes a lot of time and money to make to make a Norton dependable when it's used at high RPM regularly. Jim
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And by that time it is not really a Norton anymore. The real Norton parts on the current top "Norton" racing bikes is about down to the oil pump, the drive to the cam and the timing cover. Not really a Norton any more, vintage or vintage racing.

If it was mandatory in vintage racing to have a black box that grounded out the ignition at 6000 rpm, and to only allow original rim widths and replica road-approved tires like the old Avon Gp and Rib front, no more race compounds. How would that change vintage racing? It might let people race more cheaply, people might see more real vintage bikes on the track and it might swing the emphasis away from the mentioned money. You could even limit parts replacement to stock replacement parts. Motors would last a long time and the decreased corner speeds with the old style tires might let the chassis last a lot longer.

Vintage racing is turning into NASCAR where the only thing the race bikes have in common with the real thing is the name on the tank.

The cost of fuel, food, lodging, entry fees, track transponders, race tires, approved leathers and helmets and entry fees makes vintage racing a stretch to the married working-Joe who does not live within a few hours drive of a track. And that is without adding the cost of a replica engine, TT transmission and replica chassis.

I like watching old racers and people having fun working on and racing vintage bikes. Have not been a fan of nascar since the stock cars were eliminated from it......
 
beng said:
comnoz said:
It takes a lot of time and money to make to make a Norton dependable when it's used at high RPM regularly. Jim
Click to expand...

And by that time it is not really a Norton anymore. The real Norton parts on the current top "Norton" racing bikes is about down to the oil pump, the drive to the cam and the timing cover. Not really a Norton any more, vintage or vintage racing.

If it was mandatory in vintage racing to have a black box that grounded out the ignition at 6000 rpm, and to only allow original rim widths and replica road-approved tires like the old Avon Gp and Rib front, no more race compounds. How would that change vintage racing? It might let people race more cheaply, people might see more real vintage bikes on the track and it might swing the emphasis away from the mentioned money. You could even limit parts replacement to stock replacement parts. Motors would last a long time and the decreased corner speeds with the old style tires might let the chassis last a lot longer.

Vintage racing is turning into NASCAR where the only thing the race bikes have in common with the real thing is the name on the tank.

The cost of fuel, food, lodging, entry fees, track transponders, race tires, approved leathers and helmets and entry fees makes vintage racing a stretch to the married working-Joe who does not live within a few hours drive of a track. And that is without adding the cost of a replica engine, TT transmission and replica chassis.

I like watching old racers and people having fun working on and racing vintage bikes. Have not been a fan of nascar since the stock cars were eliminated from it......
Click to expand...


All very true, however I have still seen "average Joe" go out after spending chump change and win races. I have been beat by them more than once. It is still the rider- not the bike that wins a lot of races. Jim
 
beng said:
comnoz said:
It takes a lot of time and money to make to make a Norton dependable when it's used at high RPM regularly. Jim
Click to expand...

And by that time it is not really a Norton anymore. The real Norton parts on the current top "Norton" racing bikes is about down to the oil pump, the drive to the cam and the timing cover. Not really a Norton any more, vintage or vintage racing.

If it was mandatory in vintage racing to have a black box that grounded out the ignition at 6000 rpm, and to only allow original rim widths and replica road-approved tires like the old Avon Gp and Rib front, no more race compounds. How would that change vintage racing? It might let people race more cheaply, people might see more real vintage bikes on the track and it might swing the emphasis away from the mentioned money. You could even limit parts replacement to stock replacement parts. Motors would last a long time and the decreased corner speeds with the old style tires might let the chassis last a lot longer.

Vintage racing is turning into NASCAR where the only thing the race bikes have in common with the real thing is the name on the tank.

The cost of fuel, food, lodging, entry fees, track transponders, race tires, approved leathers and helmets and entry fees makes vintage racing a stretch to the married working-Joe who does not live within a few hours drive of a track. And that is without adding the cost of a replica engine, TT transmission and replica chassis.

I like watching old racers and people having fun working on and racing vintage bikes. Have not been a fan of nascar since the stock cars were eliminated from it......
Click to expand...

This is getting a bit off topic BUT iIt comes down to how bad do you want to feel good, as already stated, machinery is not everything.

You must enter a race to have a chance to finish. You must finish a race to place. Sometimes the advanced motors and bikes are the owners own worst enemies. New tire technology is a "no brainer - safety"; I suppose the true purists would expect racers to run with period personal protective gear but then there would probably not be any left due to natural attrition (selection?).

From what I have seen, the cost of building a very advanced bike is chump change compared to the costs of travel, rooms/lodging, food, entry fees, vacation time, hospital bills and the carnage it may or may not have on ones relationship with others. So if you are going to do it, don't dick around but do it in a big and proper way or do it as one sees fit. It really does not matter if you want to do it, just go do it and don't make excuses.
 
Jim, any chance of some pics of you valve jobs as a guide, close ups if possible?
Regards Mike
 
Brooking 850 said:
Jim, any chance of some pics of you valve jobs as a guide, close ups if possible?
Regards Mike
Click to expand...

I can try. My camera equipment is not up to my engine equipment.

The first shot is a standard 3 angle cut. The black shows the 60 degree cut, the silver is the 1mm wide 45 degree seat and the red is the 36 degree cut leading into the chamber.

Head flow testing.


The second shot shows what the valve looks like after a little lapping. It is hard to see but there is a 1mm wide gray stripe roughly centered in the sealing area of the valve.

Head flow testing.


If you want to get tricky you can install a 1.5mm oversized valve on the stock seat. Kibblewhite or I stock them.

Head flow testing.


I then add an extra angle cut of 52 degrees between the 60 degree cut and the 45 degree cut. The 45 degree cut will come nearly to the edge of the seat insert. This shot shows how I have blended the 60 degree cut and the 52 degree cut into a radius cut with a carbide burr.

Head flow testing.


If you use the oversize valve you will want to check for valve to valve clearance at overlap. You want at least 1mm. It's not normally a problem with a stock or mild cam. If you don't have enough clearance you can sink the exhaust valve deeper into the seat.

The exhaust seat is cut the same. There will be little if any 60 degree cut as the ID of the seat is nearly as large as can be used already. The 45 degree angle cut will be a little wider. About 1.5 mm works well. The witness mark on the valve will be closer to the edge of the valve after lapping. The 36 degree cut will be much wider.

Note the 80 grit finish on the port. If you polish the port it makes it hard to get the engine to carburate cleanly as raw fuel tends to run down the wall into the chamber.

There are some more pictures here : >>http://s658.photobucket.com/albums/uu310/comnoz/Projects/<< Jim
 
For those that want to keep this subject flowing in their head on various levels try this article that uses Golden Era car and cycle engine as examples both good and bad. Stumbled on searching vortex generators and mentions where to add those.

http://www.bmw-m.net/techdata/cylinder.htm
 
Nick Glantzis , appears to be the author .

While were here , WHAT would a 73 odd 750 head with 1/8 oversize intakes , stock , be . please. Pray Tell .
30 odd mm ports , probbly the 30.5 ones not the 28.5 . :? Had em done to 32 at intake gasket tapering on in .
 
hobot said:
Patent on port and valve vortex generators to churn over.
http://www.patentgenius.com/patent/4744340.html
Click to expand...

Although this may have utility in lean burn technologies or striving for higher fuel efficiencies it looks like it would wreak havoc on converting the port kinetic energy back to static energy ie. performance killer. It appears that the graph they supply shows just that - greater pressure drop for same flow rate so WTF if you are looking for performance (other than maybe economy.

That kind of turbulence in the combustion chamber (assuming better than a standard valve) - good. That kind of turbulence when trying to fill the combustion chamber as rapidly and efficiently as possible - bad.

With a poppet valve port you are trying to get a perfect veturi where you attempt to convert potential energies (at the bell mouth and inside the combustion chamber) into kinetic energy and back as efficiently as possible (See Bernoulli). The only other constraints are sonic choke and time available to do it. What you have going for you is harmonic tuning.

Best engines for turbulence are flat heads. Four valve heads tumble whilst two valve heads (who knows, varies on configuration) although the Norton head has some special geometries (dumb luck in my opinion) which induce very good swirl.
 
The weather vane size valve patent looks like a child's joke to me or lack of testing or understanding of size, number and placement of VG's. I agree with Dances summary in this example but not the principle, I think... I'd say mote like flutes on the valve stem and guile and dimples or tiny spikes on some areas on back of valve head. Two valves add more swirl that lingers near TDC than 4 valve unless valve size &/or valve opening staggered. I'm half mad G force junky on small ports after accidentally getting it about right by mismatched manifold to port stepped face and a crude expedient wire embedded heat carb gasket. Don't know what applies in more extremist builds, just sense there's addition flow magic to come.
Peel's forks might end up like this whale

Head flow testing.
 
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