Author Topic: Team Go Dog, Go! Modified Partial Streamliners  (Read 1438573 times)

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Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #105 on: March 16, 2010, 01:49:49 AM »
Yes, I have heard, that in some places and on some nights, there can be wild things happening in airport lounges.

"Model and Pattern Making for Vintage Vehicles" is the presentation topic this Saturday, 20 March, at 10:00 AM, in the North West Vintage Car and Motor Cycle Museum at Antique Powerland in Brooks, Oregon.  www.nwcarandcycle.org  This is a talk about making patterns and casting parts for vehicles and other uses.     

   

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #106 on: March 17, 2010, 12:55:46 AM »
The fairing is done.  It is a good feeling to actually finish something.  Five or so years ago I was struggling with the fairing aero design.  The pointy and wedge shaped fairings were not looking good.  Too much energy lost in rearward turbulence.  The air should be traveling parallel to the line of travel when it flows across the fairing trailing edges.  One of my old hot-rod books discussed the Batchelor-Xydias So-Cal streamliner.  It was a pioneer design having a boxy shape with rounded corners.  It was extremely fast in its day.  I did a lot of figuring and this shape looked best.  The initial shape had some aero problems and they have been worked out over the years.  The hippopotamus look.   

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #107 on: March 18, 2010, 11:00:55 PM »
The salt quickly strips the zinc plating from parts.  The zinc oxidizes more readily than the underlaying steel.  It sacrifices itself to protect the steel and it is effective until it is used up.  Normally the parts are replated, but this costs a lot of money, and some parts are hard to replate.  These braided oil lines and banjos are examples.  The Team Go Dog, Go! low budget method is used instead.

First, the parts are removed and cleaned.  Pieces with some intact plating are cleaned with a brass brush.  This removes the rust and it leaves the plating.  Parts with all, or almost all, of the plating gone are cleaned using a wire wheel or similar.

Next, the parts, including nuts and bolts, are sprayed with cold galvanize. 

Last, the parts are sprayed with a light paint coat.  "Cast Iron" color resembles Triumph anodizing.  Silver look like zinc plate.  The paint top coat greatly extends the coating's life.

Wrenches and other abuse knocks off some of the zinc.  This is not a problem.  The part will be protected as long as there is zinc on it.



 



 

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #108 on: March 21, 2010, 04:03:27 PM »
Engine port work is sometimes called "free horsepower."  It is a means to get more performance from an engine without a lot of added cost.  There are several kinds of port work, and they vary in complexity.  The simplest option is leaving the ports alone.  This is a good idea on engines whose ports are at optimum shape when they come from the factory.  My old BSA Spitfire was an example and the BSA Gold Star is another.

Blueprinting is the next most complex example.  The ports are smoothed and cleaned to remove manufacturing defects.  This can be done by the home mechanic.  It can provide better performance and often it is all that is needed.

The porting job is more extensive.  The ports are reshaped to provide optimum flow.  This is best done by a professional using a flow bench.  The ports can be opened in the appropriate areas, and ports on multiple cylinder engines will have similar flow characteristics.  This provides smooth running and better performance.  This is the best option for most street engines.  It provides better performance throughout the power band.

The most radical job is Bonneville porting.  The ports are opened way up to flow as much air as possible.  The atmosphere at the salt flats does not contain much oxygen and naturally aspirated engines need all of the air they can get.  This work is best done by a professional that is experienced with LSR.  My Bonneville has LSR porting done by South Bay Triumph.  The benefits are at higher RPM.  Low to mid range power is not significantly improved.  This is excellent for lake racing.

Engineers imagine ports where the holes in the head match the holes in the intake and exhaust manifolds.  They imagine smooth shape transitions throughout the intake and exhaust tracts, and the openings in the steel valve seat inserts are always aligned with the ports in the aluminum head casting.  This is seen on the Honda 450 engineering drawing.  Making a manufactured item match the original design is called "blueprinting."  Old drawings and plans were on blueprints. 

Werner's cylinder head was made by people in a hurry.  It is awful.  The next few posts will show how it is reshaped so it matches the engineer's original concept.  Blueprints are no longer used, but we have one on our shop wall.  It as a steam locomotive.   

    a       

Offline Seldom Seen Slim

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #109 on: March 21, 2010, 07:20:05 PM »
WW, thanks very much for the nice textual explanation.  My dad, in Austria, has been wondering why people do such a goofy-sounding modification - especially if it doesn't gain much, as he says.  I cut and pasted -- and sent it to him.

By the way, his initials are WW.  What a coincidence, hey?

Thanks again.
Jon E. Wennerberg
 a/k/a Seldom Seen Slim
 Skandia, Michigan
 (that's way up north)
2 Club member x2
Owner of landracing.com

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #110 on: March 22, 2010, 09:36:55 PM »
Opposites attract.  One of my parents was of German background.  "Don't monkey with it.  You are not worthy.  The people that made it know what is best."  I heard this a lot.  The teutonic stuff is well designed and there is a bit of truth to this.  The other parent was of strong British descent.  She loved drag racing and had no problems with redoing anything.  An English trait.  This is appropriate, the British things needed a lot of hands on work to live with.  More budding mechanics were educated by owning a British sports car than any trade school.

Port work requires special tools.  One is a good light.  The one I use has a circular florescent bulb with a 3-diopter lens in the center.  This provides +75 percent magnification.  Another 8 diopter lens can be added to give +275% magnification.  Great for brain surgery.  The light is made by Dazor in St. Louis at www.dazor.com.

A nicked intake valve is shown in a photo.  Valves undergo a lot of heating and cooling cycles and a crack could grow from this nick, with horrible results.  This is one example of the light's uses.  Inspection.

 

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #111 on: March 24, 2010, 01:38:54 AM »
Grinding and polishing tools, along with fingers and sandpaper, do the job.  An air grinder is shown with a few bits, burrs, and grinding stones.  Some of the most useful are the flame shaped bit for cutting and the bristle wheel for polishing.  I could not find mine to show in the picture.  They are shown in the Fastenal catalog.  The little Dremel electric tool is handy and it is most practical for little ports.

Holding a tool for a long time is tiring.  I attach the air hose to the ceiling and the tool hangs down from it.  I hang the Dremel tool from the ceiling, too.  The photo shows the setup ready to go.  The light is on and the tools are ready.

The new high quality synthetic sandpapers work very well on metal.  The coarse 80 grit works best for me. 

Offline Freud

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #112 on: March 24, 2010, 11:39:26 AM »
Wobbly, you are doing a fine job.

FREUD
Since '63

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #113 on: March 25, 2010, 01:45:14 AM »
Thanks Freud.  Some of this stuff I learned in dinosaur times.  Maybe someone will tell us about new and better ways to do things.  The following must be on a spreadsheet somewhere.

Some figuring is needed before the cutting and grinding commences.

The intake valve closes and a pressure wave reflects back along the inlet tract.  The pressure wave exits the velocity stack and another pressure wave is reflected back into the intake tract.  The pressure wave, if it arrives at the wrong time, can hinder flow into the cylinder through the open intake valve.  The wave, if it arrives at the desired time, can push additional mixture past the intake valve and into the cylinder.  The intake tract length can be adjusted so the pressure wave arrives at the intake valve at the correct moment.  This is ram tuning.

There are some pretty fancy formulae to figure out intake tract length based on cam timing and other factors.  This is a bit complicated for this post.  A simple method will be explained.  It gets a person close to the optimum solution.  This procedure is from a 1970 article "Four Stroke Tuning" by Jerry Branch and Le Roi Smith in Petersen Publishing's "Motorcycle Repair Manual."  Jerry Branch was an expert in engine air flow.  This is, as Jerry says, "A formula from an English engineer" and it is best suited for racing engines.

First, the speed of sound is needed at the race location.  Bonneville is at 4200 feet elevation and it is 70 degrees when we race, on the average.  The speed of sound is 1090 feet per second in these conditions.  This is "V" in the equation.  Next the engine speed is needed during the peak ram effect.  This is a matter of personal preference.  I use 80% of redline for initial trials.  0.80 x 9,000 = 7,200 rpm for the little Honda.  This is "N".  "L" is the intake tract length in inches.

The formula is L = (90 X V) / N       L = (90 x 1090) / 7,200 = 13 5/8 inches for the little Honda.   


Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #114 on: March 27, 2010, 01:42:49 PM »
The speed of sound in the previous post was from an online calculator I found on the internet with no supporting calculations or data to substantiate it.  This was a dumb move on my part.  I went back and did some research in my old books and on the internet.  The calculator at www.sengpielaudio.com seems to be a lot better.  It uses the classic accepted formula.  The speeds of sound are 1110 feet per second in 50 degree F air to 1170 feet per second in 110 degree F air, with a variation of 10 feet per second per 10 degrees F in between.  Against intuition, the sound speed is primarily related to temperature, and it is minimally affected by barometiric pressure or humidity.  Branch used 1100 feet per second in his article.  We usually ride in 70 degree weather, on the average.  The sound speed is 1130 feet per second.  Werner's ideal intake tract length is 90 x 1130 / 7200 = 14.13 inches.

A wire is bent to match the middle of the inlet tract.  One end is at the face of the intake valve.  The other end sticks out of the intake port.  A roach clip is clamped onto the wire and it is flush with the end on the intake tract.  The wire is straightened out and measured.  It is 4.50 inches long.  The carb is 3.19 inches long.  These added together are 7.69 inches.  There are 14.13 - 7.69 = 6.44 inches between the carb end and the ideal inlet tract length. 

Werner made a velocity stack bell out of an old copper pipe,  We will make new bells in 5.44, 6.44, and 7.44 inch lengths for the dyno testing.       

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #115 on: March 30, 2010, 01:25:41 AM »
The inlet calculations show that the velocity stack length can be tuned to give the desired ram air effect.  The carb manifold is not too long.  The manifold needs to be enlarged slightly, about .5 to 1 mm, throughout its length.  Then, both manifold ends will be the same diameter as the carb.

It is difficult to remove a small amount of metal over a large area with a cutter or burr.  They are best for cutting larger amounts of metal from small areas, such as enlarging cavities.  The sanding flapwheel is used to enlarge the manifold.  It removes metal evenly from a large surface area.  The inside calipers are used to periodically check the inside diameter.

The flapwheel is part of a family of tools that are not cutters or burrs, as shown in the photo.  The flapwheel is a metal removal tool.  The spidery looking detail abrasive brush is another metal removal tool.  Both of these tools can be used to smooth out cutter and burr worked areas.  The donut looking spongy things are finishing abrasive brushes.  They are not for removing metal, but they work great for finishing the ports.  The finer black one is excellent for carbon removal.  The wire brushes can be used to polish out small imperfections.  They are delicate tools and they are not suited for heavy work.

Light always seems to be a problem when doing this work.  The little headband light is a great help.  These lights use LED bulbs and they go for a long time without needing recharging.

The manifold is enlarged to match the carb inside diameter and it is smoothed using abrasive brushes and sandpaper.  There are no casting marks or other imperfections.  It is done and now it is time to work on the inlet port.


Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #116 on: April 03, 2010, 01:44:22 AM »
The web address http://yamaha-motor.com/sport/products/modelinnovation/209/0/innovation.aspx shows the 2010 YZ450F motocrosser.  The engine is tilted backwards and the exhaust pipes exit the rear of the cylinder head.  All of this provides straight ports that flow well.  A future trend?

A problem with port work is knowing where to stop.  It is not good to enlarge the port and bore out into a water passage, etc.  Werner's intake and exhaust ports have big lumps in them near the valve guides, as shown in the photo.  It would increase flow if I ground them down.  The valve spring pockets are above the lumps.  Can I smooth out these lumps without breaking out into the valve spring pockets?

A heavy duty piece of paper is taped onto the drill press table and the cylinder head is placed on it.  Two magnetic dial indicator stands with pointers are put on the table.  The upper pointer sticks into the bottom of the valve spring pocket, and the lower pointer touches the underside of the lump, as shown in the pictures.

The outline of one indicator base is outlined using a fine pencil.  The pointer base is demagnetized and it is removed, along with the cylinder head.  The pointer base is carefully placed back on its outline.  Now it is in its original position.  The gap between the pointers is measured.  The gap distance is the same as the metal thickness between the outside of the lump and the inside of the valve spring pocket.  The distance is only 3/32 of an inch.  This is not very much metal.  I will not grind down the lumps.



 

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #117 on: April 03, 2010, 01:46:01 AM »
The last two photos for the previous post

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #118 on: April 04, 2010, 03:17:52 PM »
The port throat is the area just upstream of the valve seat on the intake port, and the reverse on the outlet port.  The most common error from sloppy manufacturing is to not align the steel valve seats with the aluminum head casting.  The seats on this little bike were 1mm offset from the casting.  This is a lot of error in these small ports and it retards airflow in a critical area.  Cutters or burrs are used to remove aluminum, as needed, to match the seat to the head.  Grinder bits are used to remove valve seat material.  Care is used to make sure the portion of the seat that is contaced by the valve is not harmed.  The photo shows a completed job of matching the intake valve seat to the intake port.  Work is in progress on the exhaust valve seat.  The black is laundry marker ink.  This is used so I can easily see the high and low spots on the port and seat while grinding and cutting.

Next, the exhaust pipe header inner diameter is checked and it is reasonable for the type of use.  The info on the website a few posts previous is used.  There is a large weld at the inside of the header entrance.  It is ground down.  Some restraint is used.  Enough weld remains to hold the pipe together.  The exhaust port exit is matched to the exhaust pipe and the exhaust pipe gasket.  There is a smooth transition from the cylinder head to the header.     

The last step is to smooth all casting marks and defects out of the ports.  Usually this is a sandpaper and fingers job.  It is something intellectual to do while watching Sponge Bob reruns.  Feel is the best quality control here.  Surfaces in the ports should feel nice and smooth to the touch.  Occasionally there are places that are hard to sand with fingers.  Sandpaper on a chopstick will help.

Almost all shop manuals for modern motorcycles show a multi-angle valve job and they give recommended valve seat widths.  The Honda manual does, and the seats on this bike are slightly wide.  It is important that the seat widths are correct in order to have best performance.  We will do this in the future when the bike needs a valve job.  The seats are good enough for now, and the valves are lapped in using conventional methods.  This concludes port blueprinting part of this build.

The Triumph has ten runs down the salt and 20,000 street miles.  It is time for a new cam chain and a look-see inside the engine.  Of course, I am a typical hot rod guy, and there is no way that engine is going back together without some performance mods.   

 

Offline wobblywalrus

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Re: Team Go Dog, Go! Modified Partial Streamliners
« Reply #119 on: April 06, 2010, 12:39:40 AM »
About this time last year, Mr. Noonan was responding to a question about tire pressure.  He runs between 30 and 40 psi in his tires.  This is a lot lower than the pressures I was using.  Also, I made the switch to a radial rear tire from a bias ply.  The first time I ran the setup was in 2009.  It works very well.  I have more traction and control.

My tire slip factor must be recalculated.  It is an essential part of the basic gearing formula for engine RPM vs speed.  My 2009 down run was 127.2 mph and the tach showed a steady 7,500 rpm through the mile.  I was very tired on my return run and I did not look at the tach.  I wanted to get off the bike, finish the displacement check, have a stiff drink, and go home.  The slip factor is redone based on the one run.  Several runs should be made to get a good idea about the factor, and this will be done this year.

The basic gearing formula is shown with all of the factors.  The gear ratios are from the shop manual.  The tire circumference was measured using Rosie's dress tape.  These formulae are bike specific, and they are for "Bonnie" the Triumph.  My dirt bike "Thrasher" has its own equations.  The slip formula includes tire slip and tachometer error.  I always use the same tach so this is not a problem.

The new slip factor is 3% for good salt.  As a reference, my old slip factors were 5% with the bias ply tire and 45 or 50 psi on good salt, 7% for slightly wet salt, and 10% for sloppy wet salt that I should not have been racing on.