Team Go Dog, Go! Modified Partial Streamliners

[wobblywalrus]

Lots of copper washers are used when the Triumph is switched from street bike to salt dog and back to road trim.  Oil drain washers, brake line washers, etc.  The old washers are compressed and work hardened.  They are not good at sealing when they are in this state.  I put the used washers on a wire and heat them up to orange hot.  Then I dunk them in water.  This anneals them, makes them soft, and they are ready to be used again.  I keep the washers on two metal clips.   

[wobblywalrus]

It is time to do some engine work on the Bonneville.  The cam chain is worn and whipping around, and the standard pistons and rods have been run for three years at Bonneville and 21,000 miles on the street.  The 2008 runs were real brutal.  Compression is fine and there is no piston slap. I simply want to put in racing quality components.  A fragged piston or snapped rod would end my land speed career.

The big decision.  Should I build a hot engine and go for records in my 1,000cc modern engine classes?  Should I build a strong, but not radical, street motor?  All of us face this decision.  I have a few times.  A hot engine requires a lot of money, hours with the spanners, and maintenance.  This time, for once in my life, I decided to put thought before action.

The benchmark in my class, a threat to all records I could attempt or set, would be a new BMW S 1000 RR.  I would have to equal or exceed this bike.  Advertised specs are 190.42 horsepower at 13,000 rpm for an engine just under 1,000 cc.

Consider volumetric efficiency.  I could bore and stroke the Triumph out to 1,000 cc and produce 120 hp, naturally aspirated.  This would take lots of money and I would need to tear it down after every session on the salt to check the bearings, etc.  Volumetric efficiency would be about 120 hp per liter.  The BMW has about 190 hp per liter when you roll it off the showroom floor.

Let's look at redline rpm.  Assuming two engines have equal volumetric efficiency, the one with a higher redline can run gearing with a greater numerical ratio.  This engine will exert more leverage on the track and it can go faster.  Right now I run the Bonnie between 7,000 and 8,000 rpm through the mile.  Folks with higher tuned Bonnies stretch them out to 9,000 rpm.  The BMW, out of the crate, has an advertised redline of 13,000 rpm.  Clearly, the Bonnie has no hope of being a serious land speed racer.  This has been for awhile, and is getting to be more so, the era of the four.

The one thing the Bonnie is real good at is racing for the pleasure of going faster every year.  It is relatively easy to work on and not very expensive to hop up.  Besides, it is paid for and a harmless old guy on a slow bike can run in most events.  Elvington and Lake Gairdner await.

This winter the engine rebuild will be posted.  It will be basic, but folks who have not torn down a motor might learn something.  Lots of younger people have not taken an engine apart.  It will be awhile.  I have to save up money for the parts.   

[wobblywalrus]

This Bonneville has never idled smoothly and occasionally it dies at stoplights.  Porting the engine and installing pod air filters made it worse.  Just before the BUB Trials, I remembered a trick we used on BSA's, Triumphs, and Nortens years ago.  It works on twins whose pistons go up and down together and fire on alternate strokes.  I have also used it on four cylinder Hondas, cylinders 1 and 4 are connected and 2 and 3.

First, I drill and tap a hose fitting on each manifold.  They should be the same distance from the intake valve on each cylinder.  The Triumph has these already installed at the factory.  Then, I synchronize the carbs with a vacuum gauge.  Last, I do not cap the hose fittings.  Instead, I connect the two pipe fittings with a piece of fuel line.

This little fix smoothed out the Triumph and gave 2 or 3 more miles per gallon.  This is not unusual. 

[wobblywalrus]

Economic reality being what it is, the engine project is now the bare minimum that is needed to race next year.  A new cam chain will be installed, along with new racing rods and larger high compression pistons.

Land speed racing puts a lot of strain on the engine.  Triumph pistons are forged.  I do not know about their long term durability, although they have been OK so far.  I do not want to take chances.  Racing grade pistons are not available in the 790 cc size, but there are some for the 865 cc engines.  I looked at the cost of boring out the 790 jugs and putting in sleeves for 865 cc pistons.  The sleeves would be steel or iron.  The Triumph cylinders are not sleeved.  The bores are a hard plating on the casting and this gives excellent heat dissipation.  I do not want to have a seizure on the salt, and learn the hard way, why Triumph does the things they do.  I ordered a new set of 865 barrels.  They are the same casting as the 790 cc jug with bigger holes.

I could order the pistons directly from South Bay Triumph and put them in myself.  Barrels and pistons are manufactured items and it can be assumed they will be slightly bigger or smaller than the design dimensions. I will send the barrels down to South Bay and ask them to fit a set of pistons and to make sure the skirt to barrel clearances are the best that they can be.  This will be work for them and I will gladly pay for it.  South Bay has Carillo racing rods.  I will order a set, also.

Rod and crank bearings are plain shell inserts.  The crank is hard plated and it cannot be ground to fit undersize shells.  I always put in new shells regardless of whether or not they are worn beyond the limits.  My goal is to get maximum life from the expensive crankshaft.  Oil filters do not sieve out all of the abrasive contaminants.  Some get through and they inbed themselves in the soft bearing shells.  These particles can grind away at the crank journals and reduce their life.  New bearing shells, renewed periodically, can save $ in the long run.

In past years when I had more money and less time, I would send the crank and cases out to a shop with a stock of bearings and ask them to fit them.  These Triumphs are so reliable that our local dealer does not have bearing shells.  I will need to send the engine parts far away.  Now, with more time and less money, I will save shipping costs by bringing the crank, cases, and rods down to our local machine shop.  They will measure them and I will order the right sizes.

All of this takes some planning at the kitchen table.  I read the engine section of the manual completely and order all of the parts they say should be replaced, such as lock washers, gaskets, seals, etc.  I make sure that I will have all of the tools that I need.  I order all of the stuff that I know I will need beforehand.  This minimizes downtime. 

[wobblywalrus]

It will take a few months to save up the money for rods and pistons.  Now is the perfect time to work on streamlining the streamlining.  Looking at the bike from above, the fairing lower half has a wedge shape with the pointy end facing forward.  This seemed like a good idea at the time.  Now I know better.  The streamlining should give the bike an egg shape with the blunt end facing forward.  The fairing sides need to be curved inward.

Sheet metal must be removed from the rear of the the fairing side.  The rivet line between the old and new sections should match the rest of the fairing.  Tape is laid across the fairing using a trial and error method.  Finally a nice looking seam is marked.  The sheet metal is cut away to the rear of the tape line.

The aluminum bar at the upper fairing edge needs to be bent in a gentle inward curve.  The bar has lightening holes in it.  The metal will tear at the outside of the bend near a lightening hole if I am not careful.  I need to keep the metal on the outside of the bend from stretching while I compress the metal on the inside of the bend.  A steel strap is tightly clamped on both sides of the bend to the outside edge of the bar.  It will not stretch.  The bar is annealed on the inside of the bend.  Lots of force is used three times, with three heatings, to bend the bar into a gentle curve.  Compression bending is a lot of work, but there is no danger of overstretching the bar on the outside of the bend.

[wobblywalrus]

In my youth I had more strength than brains.  I did a lot of cold bending.  This takes a lot of force and often the items a part is attached to are bent while straightening the desired piece.  Then I discovered heat.  I heated all sorts of parts to red or orange hot and bent them with little force.  Unfortunately I annealed them and they lost their temper and strength.  Some alloys did not glow red hot.  Instead, they did not glow at all, then they got hot enough and they melted.  I learned not to take the torch to parts with "magnesium" stamped on them.

I did learn that a little heat combined with moderate force works best.  My usual method now is to:  clamp the part so the sections that are not to be bent are fixed in place, apply moderate pressure to the part and at the same time apply heat, heat and apply force until the metal relaxes into the desired position, and remove the heat and force.  I use as little heat as possible so the metal does not lose its temper.  Often I do not know how the metal will act.  I start with propane and see if it will do the job.  Then, I use a hotter gas like map gas, if needed.

This method seems to take three or four hands; one or two to steady the work, one to apply the bending force, and one to hold the torch.  Unfortunately, I am not a four handed monkey, so I use all sorts of straps to act as surrogate hands.  The pictures show some methods I used to bend a piece on the Triumph fairing.  Note the little bending tool I made from a bearing puller.   

[wobblywalrus]

The aluminum frame started out being the bare minimum that was needed to hang the sheet metal on the bike.  Then the bike was ridden over some rough roads and the fairing bounced and flexed around.  Braces were added as needed to stop the flexing.  Lots of drilling was used to minimize weight.  Backwoods engineering.

The thicker sheet aluminum is 0.030" thick.  It is used in stressed areas.  The remainder is 0.020" thick.  Thin 0.015" aluminum works, too.  It dents easily so I do not use it for this land speed fairing.  This thinner stock would be used for a drag or road race fairing.  Light weight is critical for these applications.  Welding 0.020" aluminum is too difficult for me.  I use pop rivets to join the panels.

The aluminum pieces are laid over each other like fish scales.  The upper edge of one plate overlaps the lower edge the other plate by 1/2 inch.  A guide bar is clamped on the fairing to show me the curvature and location of the far edge of the plate row.  Arrows are drawn on the bar to show me where each plate corner should be.  Plates are shaped and added, one by one, until the row is complete.  The guide bar is moved so it lines up with the edge of the next row, and the procedure is repeated.

I could use a lot fewer and bigger plates than I do.  The bigger ones take a lot more skill and patience to make than I have.  I do this after work in the evenings when I am tired and my thinking is done for the day.

   

[wobblywalrus]

A local shop is interested in Werner's racing.  They asked him for a resume.  It is not a job resume.  They want to sponsor him.  Does anyone know how to write a sponsor resume?

[1212FBGS]

yep.....
kent

[wobblywalrus]

oh can you send us a copy of one that someone else did so we can see what we should do

[wobblywalrus]

The object of the fairing rebuild is to reduce the frontal area and to lower the drag coefficient.  The fairing has flared sides and this creates a large turbulent wake behind the bike.  Making this turbulence requires a lot of the engine's energy, and I have better uses for it, like going faster!

The bottom of the fairing remains flared.  It does this so my feet are kept in out of the wind.  The mid section curves around the engine.  The wind should be parallel to the bike's sides when it spills off from the fairing trailing edge.  One side of the fairing has been reworked in the photos and the other side remains flared.  The flared side will be rebuilt in the next few weeks so both sides will be matching.

[wobblywalrus]

Beating up poor innocent metal pieces is a big part of Team Go Dog, Go.  We cannot buy much so we make everything we can.  The next few posts show the basics.  These are intended for folks starting out with racing.

Anvils are a good place to start.  I do not like to beat hardened steel on my anvil.  The struck object can leave a scar on the top face.  Also, I do not like to beat stuff with heavy blows on the anvil for the same reason.  A section of railroad rail is used for this rough work.  Not all train track is the same size,  this is a chunk of the Southern Pacific mainline through Salem.  It is nice and heavy and it does not slide about on the workbench.  The anvil is a Chinese job.  I said to myself "I'll buy this thing, how could anyone screw up when making an anvil?"  The grey paint covers a layer of filler over a very rough cast surface.  I should have bought an old American anvil.

Hammers are essential.  These are three ball peins of different weights.  Never hit the hammer directly on the anvil or track.  Always have some object between the two.

The little vice is a 4-inch model.  It is mounted on a workbench corner a few inches above belly button height.  This makes close and intricate work comfortable and easy to see.

The big bruiser is a 5-inch heavy duty model.  It is solidly mounted on a workbench at butt height.  The bench is solidly weighted down by the drill press, air compressors, the bench grinder, and all sorts of other junk.  The vice corner sticks out into the shop so it can be reached from three sides.  This low height and location makes the vice easy to use for heavy bending and other work.

Many of us are on a budget and these tools seem to be expensive.  They are when they are new and I buy some stuff retail.  A lot of my other tools are bought used, scrounged from old abandoned buildings, or given to me.  Tools do not need to be new and cost a lot to be good.  A lot of the old stuff is better quality. 

[wobblywalrus]

Fire is another tool.  The firewrench.  I have a couple of bottles of propane on hand.  This is a cooler burning gas and it is useful for annealing aluminum sheet, lighting barbecues and cigars, killing spiders, and other light work.  It is in the blue bottle in the photo.  The yellow bottle in the photo is full of map gas.  It burns hotter and it is the most useful for bending.  I use a lot of it.  In general, I find that using a hot torch is best.  I can work quickly and keep the heat in the desired area and it does not spread through the part.

A pencil tip is often sold in starter kits.  It is easily controlled and it is useful for soldering.  It is not much good for heating prior to bending.  It is shown in the photo attached to the propane bottle.  A heavy duty tip is most useful for heating and annealing.  I use it 90 percent of the time.  It is attached to the yellow bottle.  We call it the blowtorch.  The spreader works with the blowtorch to fan out the flame.  It is great for thawing pipes and burning off paint.

There are jets for these things.  They look like motorcycle main jets, and the correct jet needs to be used with each tip.  These torches are not expensive and I find it handy to set up separate pencil and blow torches.  This makes it much easier to change from one flame type to another.

There are some things to remember when using these tools.  First, have a fire extinguisher handy.  Second, be careful.  In an ideal world these torches will turn off when the valve is shut.  In reality, occasionally they will not close all of the way and the flame will retreat into the tip but it will not go out.  Also, sometimes the gas will leak out of the bottle if the torch is attached overnight.  I always unscrew the torch from the bottle immediately when I am finished.  In the next post some metal will be bent.

 

[wobblywalrus]

Anyone who has made the aluminum bars like I use with the holes drilled in them knows how hard it is to bend them.  They tend to tear at the outside of the bends near a hole.  The cross-section is the smaller where there are holes and the bar is weaker.  The bars should be bent then drilled.

Sometimes a drilled bar needs to be bent.  Several posts previous I showed how to bend a bar with a piece of metal clamped to the outside edge.  This forces the inside edge to compress when the bar is bent.  Another way is to apply bending pressure and to heat the inside of the bend with map gas.  The heat will soften the metal on the inside and it will compress.  This will not work well with propane.  The hotter map gas is needed.  The photo shows the compressed sections near the holes on the inside of the bend.

The typical bench mounted swivel vise is too weak for bending metal.  The swivel tends to rotate.  Adding a brace prevents this.  The far end of the brace shown in the photo is clamped to the workbench.

In one photo I am heating the inside of a bend while I am pulling the bar toward me.  The orange tool I am using to pull the bar is a concrete reinforcing rod bender.  These are inexpensive and they can be bought from construction supply stores.  They are a handy tool for a fabricator.

[Dakzila]

Wobbly,

Great thread..finally got a chance to read the whole thing this morning.

 Some really good info for a racers like me that only has a drill press, compressor, vice and a "fire wrench" (love that term, don't know why I've never heard it before) in the garage. 

Keep the updates coming....


Buzz