homemade motorcycle parts

8/19/2019 Homemade Motorcycle Parts

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Homemade Motorcycle Parts On ABudget

-or How To Recycle Useless Junk Into Rare Items And Freak Out Your e!g"#ors At

T"e $ame T!me%

By Lyle Landstrom

Introduct!on

During my colorful blue collar career where I was laid off, fired, or quit just about everyindustrial job known to man I picked up a few skills useful to the vintage motorcyclist. owthat I have a real job and a family to support, I needed a part time trade to fall back on tosupport my motorcycle habit. In the course of working out of my garage to do this, I tried lots

of motorcycle related activities. I tried painting! too much time waiting between coats, can"t doit all year as it"s too cold in the winter, needs a clean environment, and most of all, my tasteisn"t e#actly like anyone else"s. I tried wrenching as I have a degree in marine and smallengine mechanics! too committed to time constraints, never enough tools, and everyone"sbike is their baby and needs special treatment. $o I decided on limited parts production as itwas perfect for me. I can do the pattern work in the basement with limited woodworking tools. %nd I can do the foundry work in the garage. &ot metal doesn"t care what the ambient airtemperature is' but most of all, I can do it on () time.

(an has been sand casting metal for several thousand years. *he ancient +hinese had someof the best brone castings in the world for any time in history. In what is now Iraq, there werenatural draft iron furnaces with so much production that scientists think it altered theatmosphere of our planet. *here is a mine in -rance where man has been mining foundry

sand for hundreds of years. It is still considered the best naturally bonded molding sand in theworld.

If primitive man can do it in a primitive environment. *hen primitive man can do it in a modernenvironment. *he purpose of this article is to show how it can be done.

Part &once't!on

*he first thing needed is an idea. -or me this usually the easiest. $ometimes I have too manyideas and nothing gets done. In this case however, I was soliciting the I list for $port $coutBig Base engine case information when /im 0all responded with a set of factoryblueprints.

%fter careful scrutiny of these prints I decided the best course of action was to draw them upin +%D. *his was because the originals were hard to read and a +%D program allowsmanipulation of the drawing from a pattern makers perspective. I also thought that if therewas enough interest in the cases, then whomever receives a set would need a good drawingto machine them from.

%fter the +%D drawing was completed, I decided to pattern up the cam cover first. /im 0allsuggested making the cover deeper so an e#tra cam lobe could be accommodated. I decidedto do this as this e#tra depth could be machined off for a normal cover. *his surface needsmachining after casting so it shouldn"t be a problem.

Pattern Mak!ng

1attern making is like life. In life you live one day at a time but with a clear goal in mind,

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solving each hurdle in steps. In pattern making, you break up a 23D object into simplergeometric shapes which are then assembled into the goal 3 or pattern.

Because metals shrink as the freee in a mold. 1atterns are bigger than the actual part. 0ithaluminum, this shrinkage factor is usually 4567 per foot. 8r about 9:. Because I had the +%Ddrawing finished for the right case which matches surfaces with the cam cover, I mirrored thecam area of the drawing to give an inside view of the cover. I then plotted it out at 4;9: ofnormal. If I had an actual cover to work from, I could have laid it on a ?;.;; from a pattern shop product, I used aproduct that can be had at any builders supply store for about >?.;;. *his sealer serves 6

purposes! 4, it seals the wood to prevent moisture from warping it. 9, it strengthens the woodpattern. 2, it serves as a guide coat when sanding similar to a guide coat when doingmotorcycle painting. 6, it gives a very smooth surface so that the pattern can be easily drawnfrom the sand.

(any sealers can be used. I"ve had bad luck with some enamels because the sand has atendency to stick. *he polyurethane is also compatible with polyester body filler as used forauto body and gas tank repair. *his is another product similar to products sold by the patternindustry but costing many times more. *his is how the fillets were made on the inside surfaceof the pattern. %utomotive body filler is also e#cellent to use in core bo#es. It"s easier to cutthe bo# out square and fill the radius in with bondo than to use a gouge to cut out thewood.

%fter the initial bondoing and sanding, more coats of polyurethane were applied. I usuallywork better at multiple tasks than one so I coated several several patterns at once. Being anaturally lay person, I only had to clean the brush once for each coat. %fter several coatswere applied with 99; grit dry sanding between the pattern was finished.

ot all patterns are made in one piece like the cam cover. In the picture, note that I havesome riser patterns in 9 pieces. *his is called a split pattern. I made the wood pattern at adouble shrinkage factor @4 for aluminum, one for brassA which will be cast into a aluminummaster pattern mounted on a match plate. *his will enable me to make multiple pieces in onemold. It"s also a lot quicker to produce a mold using this method. *he finished risers will bemanganese brone which is very shiny yellow brass yet high strength.

O(( to t"e Foundry )garage*

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Because this is a simple pattern with a parting line on the same plane, a simple flask ischosen. *he pattern is laid on the bottom board, parting dust sprinkled over the top and thefirst layer, or lift, of sand applied then rammed with a wood rammer. I use homemade woodrammers and flasks. *he reason is because a pattern can be damaged easier with a metalrammer and metal flasks are unessessary for all but the most precise molding. (etal flasksare also very e#pensive and I"ve gotten by with homemade equipment so far. *he wood flasks

will last for years if you"re careful. I use alignment pins to align the top @copeA with the bottom@dragA part of the flask.

8nce several layers of sand are scooped into the flask and rammed, the sand is struck offlevel with the top of the flask. It is then rolled over. I like to scratch out the locations of thegates with a pick so I know where to cut them in on the other half of the mold. I also like touse a 7bob7 to locate the sprue @where the metal is poured inA. *his bob not only helpsregister the sprue, but serves as a reservoir of molten material to be drawn in as the metalshrinks in the mold. *his counteracts shrinkage. It also gives a nice surface to ram againstwhich reduces the possibility of sand 7washing out7 as metal is poured in. (y bobs are madefrom the resin plastic left over from patterns when mi#ed in yogurt containers. *he yogurtcontainer serves as a good bob mold and can be used over and over. at yogurt, stayhealthy, and have mi#ing containers. *he other half of the mold is set and parting compoundis dusted over the inside surface. *his compound, which can be pretty much any dust, keepsthe sand from sticking from one half of the mold to the other, and from it sticking to thepattern.

*he upper portion of the mold is riddled with sand and rammed in lifts until it is full. It is thenstruck off and opened.

*he pattern is 7rapped7 which means wiggled in the sand just a bit and then withdrawn. *hebob is withdrawn and the sprue, riser, and gates are cut in. I like old thin wall plumbing pipe tocut in my sprue and risers. *his same thin pipe costs big bucks at a foundry supply house. $oit pays to cruse the dumps. $ome molders use a wood pin which the sand is rammed around just like a pattern, but this way woks better for me.

*he sprue is on the right and the riser is on the left. *he riser helps gas escape while pouringand also supplies metal to the casting as it cools. Csually the sprue needs to be wider thanthe thickest section in the casting. *he gates are usually at the thick sections as well. *hereare some e#ceptions but this is a good general rule of thumb.

%fter I get a couple of molds finished, I fire up the crucible furnace. I don"t fire it up right awaybecause if for some reason the molds don"t turn out, there"s no place to pour the metal. (yhomemade ingot molds won"t hold an entire melt. I usually ram the last mold while the metalis melting. Csually it"s time to pour when I get the last one rammed.

I don"t usually pour more than three molds with one melt because the metal is constantlycooling once the gas is shut off. %luminum needs to be poured around 42?; degrees - and it

loses heat rapidly. I check the temperature with a pyrometer. 7yeballin7 by color won"t workwith aluminum. (y scrap rate went to near nil when I finally got a pyrometer. 1ouring too hotresults in gas porosity and a dull finish. *oo cold results in a mis3pour where the metal didn"tcompletely fill the mold and also in a dull finish. %lthough, these are not the only causes.

I don"t stir the aluminum at any time as that creates air entrainment. I don"t use flu# becauseit"s unnecessary for aluminum. (any books have been written about aluminum castingdefects. *his shouldn"t confuse anyone because usually the simplest solution is the best. Iwon"t delve into this subject any further.

*he aluminum is poured into the molds as steadily as possible. )ou can tell when to startslowing down by keeping an eye on the riser which is filling up with the melt.

Because this was the first time I had poured this pattern and I was e#perimenting withdifferent gates, combined with my overwhelming sense of curiosity, I 7shook out7 @removed

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the castingA from the mold within a few minutes. *his is sometimes done in industry as it"s a7poor man"s7 form of heat treating and there"s even a technical word for it.

Don"t do this with brone or brass because the castings are so hot that when you open themold the oil in the sand spontaneously ignites with the air and flares up. It takes about 2 3 weeks to regrow eyebrows. It was a drag avoiding the bar for that long.

*he sand pretty much falls off the castings. *he remaining sand that clings can be cleaned off with a brush. *he sand which is burnt needs to be reclaimed in a muller for this type of sand.(ost small scale sand casting is done with 7green sand7 that is, a sand bound with clay andwater. Because I do most my casting during the winter months, I use an oil binder. *he oilbonded sand is also more permeable which reduces casting defects. It is also not as sensitiveto how hard the mold is rammed. (ost of all, I can mold when it"s below ero.

I waited until the other castings had cooled down somewhat before shaking them out. -romthe pictures you can see that the casting that was shook out while hot is duller. *he hotteraluminum is, the easier it o#idies. *his isn"t a problem but for parts which don"t require muchfinishing it"s better to wait until they have cooled down so they look better.

Before I got my molding bench at an auction, I used this sandbo# which is where I do all myshake outs now. I have rammed up hundreds of molds in this little wood bo#.

%fter the first castings are completed. I check the fit against the part they are going to fit to. Ihave a set of beat up $port $cout cases and matched them to it. Looks good so far.

8ne of the problems was because this pattern was made for both double lobe and single lobecams. *he dimensions of the casting gets smaller as more material is milled off. I had tocompromise to make the pattern fit both cases.

I also cut one casting down the middle to check thickness, machinability, the fillets and soforth. *he sectional view is a good e#ample of the draft on the pattern. *his is very important

when designing a pattern.

%t this point, I have sent three casting to /im 0all who will machine them. I might have tochange the pattern a little based on his recommendations. By the time you will read this, I willhave started on the case patterns themselves. +urrently I"m patterning the inner primary, acoil bracket, my riser match plate, and a private job unrelated to motorcycling.

+'!logue

I hope to have shown how foundry and pattern work can be accomplished at home withsimple tools. It is an activity that grows on itself. I have been able to buy or make items as Ineed them from the small profits of my garage foundry. *here is minimal need for fancy store

bought items.

I have discovered there is a small network of home foundry people. I see the same peopletime after time at foundry related auctions. 8ne guy has his little niche doing model railroadparts, another makes steam engine parts. I"ve done award plaques in brone for local footballteams among other stuff. I do a lot of novelty type stuff as well.

I"d like the thank everyone who has helped me along the way. specially to (/ whom Iconsider my friend and who is a way better foundry man that I am. I"d also like to thank thecops for not carting me off when I added too much inc to the melt the first time I made brass.It produced a flourescent green plume that drifted about 6 feet off the ground across the streetinto the park. It was quite the effect. I don"t know what was in it. But it sure cured my sorethroat.

I"ll be more than happy to answer questions to anyone about any items in this article. $tay

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tuned for Big Base +asesE

(irroring the case drawing @belowA to get an inside view @aboveA of the Big Base $cout cam

cover @back to te#tA

Drawings

Laminating wood

+utting out pattern

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Fegistering @back to te#tA

Glued3up pattern

+hecking cam cover pattern on drawing

1olyurethane coated patterns. ote riser patterns 3and Lyle's taste in paintwork, which I find

rather attractive, but I see what he meant in the introduction... :-) Moen @back to te#tA

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1attern, bottoms3up, on bottom board in lower part of flask @dragA

$prinkled with parting dust

Fammed

$truck off


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Folled over. ote yogurt container 7bob7 @back to te#tA

1attern dusted again, and top part of flask @copeA put on

$and riddled into cope

-inished ramming

+ope lifted off

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1attern and finished mold

Feady to close for pouring

(an that"s hotE


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Last mold

$mokinE @back to te#tA

Dull @hotA shakeout

$hiny @coolA shakeout

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(ost of the pieces in the drawings have been cut out. $ome arealready glued together. I had help from aul+raft, a local furnituremanufacturer, for planing and sanding the material to the correctthickness. If you need mission style furniture, aul+raft makes the

best. aul+raft is run by Fev. aul, who it turns out, has performed alot of ceremonies for the local 7biker7 community. &e was veryreceptive to helping me and interested in the project. I am going toutilie his resources on several other projects.

*his wood pattern uses a double shrink factor. 8nce the pattern isfinished, I will cast an aluminum master pattern from it. %n aluminummaster pattern will stand up under hard use, be adaptable to modernmolding equipment and be able to be machined to better dimensionalaccuracy than a wood pattern allows. %n aluminum pattern also is

easier to withdraw from the sand and will allow a smaller draft angle. Inthe unlikely event that the demand gets out of hand for these cases, Ican turn over the wood master pattern to a real foundry and they cancast any type of molding machine matchplate pattern they want.

$ome of the outlines for the pattern layers are common to both rightand left cases. Because of this, pattering the left case will go quicker.8nce both halves are completed, I will send a set to /im 0all and Fick %bbott. *hey will machine them and make recommendations. If (r. %bbott is able to write a ++ program and is agreeable to it, we willsolicit the list for orders.

+urrently, I have both primaries, mag opening cover, and the camcover available in unmachined form. %fter these case patterns arefinished, I"m going to investigate a four speed transmission case thatwill fit $portster 6 speed gears and kicker. *he case will have atrapdoor similar to the $portster where the gears can be slid in as anentire assembly. I need to do some basic investigation first and mightneed help from the list. I think this is the best solution for the 6 speed

tranny problem. *hat is, using highly obtainable transmission gearsetswhich can be used in a custom set of cases. (y ne#t step after thetransmission housing will be to produce an entire top end. I can eitherreproduce the flathead design or modify an e#isting 8& design. *hefoundry and pattern work will be a little different for the top end as Iintend on using core bo#es or lost foam casting. ither method I haveonly limited e#perience with. %lthough investigations ande#perimentation are ongoing.

I have subsequently found out that a number of local firms are capable

and willing to do the machining on any of these items. %lthough thesefirms are highly e#perienced and work for major manufacturers, I would


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rather keep as much of this work on the list and money changing out of the picture.

Cntil these patterns are finished, I have cut myself off from theelectronic world and the unproductive distractions it offers. %t the rate Iam progressing, the right case pattern should be close to finished bythe end of the month.

B!g Base $'ort $cout eng!ne cases, New! 44.94.JJ *his page will follow the development of Lyle Landstrom"s newcrankcases.

*his project was made possible by the cooperation of the I mailingListers, and is a great e#ample that nothing is impossible, if you"ve got

someone willing to do a job K a bunch of people willing to support it byfinding the information needed providing feedback on what they wantin a new product.

Lyle, who has a page about his other castings here on the I site, hadbeen looking into making a set of "2H $port $cout cases into patternsfor casting new ones in his garage foundry. Muickly the focus centeredon which improvements should be incorporated in new cases, andquite naturally the factory 6H 7Big Base7 cases came up. %s most ofus know these were made for the 4J6H Daytona racer in smallquantities @/erry &atfield quotes various sources for the number of ?;sets in his booksA, incorporating many improvements over the earlierversions.

But where could a set of these mythical beasts be foundN

nter 7-asst7 /im 0all, winner of the 4JJJ Davenport intage races onhis 4J9H 7Boardtracker7. /im is very much into racing $couts @in factthere will shortly be pages on this website, chronicling his building of 9

hot $port $cout racersEA, and he had not only a set of Big Base cases,but also copies of most of the original factory blueprints for them...

*he stage is set for the following to happen over the winter5spring!

Lyle will make patterns for a set of cases, being not true BB replicas,but incorporating the best design features of them into the format of the7ordinary7 $port $cout cases. (ost of these new cases would be usedfor street bikes, and facilities for this should be considered. Lyle is busywith other things until after December, so please don"t e#pect the

cases right awayE @Lyle, bein a cautious man, tells me !that the casesare "ust a #$M%# until he'll have somethin to show!, but havin seen

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some of Lyle's other work, I betcha he's oin to pull this one off too.MoenA. $till, this is a great start.

*he cases will leave Lyle"s garage in unmachined form, and machiningup a prototype set for testing before they go on sale is important, butthe idea of a 7central7 machining deal could be considered. $etting uptooling for the machining of crankcases is a time consuming andcostly affair, and we could probably all save money by having only one@or a fewA places doing this, rather than each having our 7petmachinist7 do it in a hundred localities around the world. 0hile Lylewould certainly e#pect to be paid for his work, and while there is noway @I thinkNA that we can get the machining done for free, this couldstill mean new, stronger cases for your $cout project @3you have one,don't you& here are too many (hiefs out there :-) MoenA at affordable

cost. $tay tuned for this angle.

8, what"s so special about Big Base casesN &ere"s a bunch ofpictures from /im to whet your appetites. &l!ck on t"e small '!cturesto see (ull s!e .ers!ons/ and cl!ck on t"e #!g '!ctures to return"ere @or use your browser"s 7back7 buttonA. In all modesty, this is kindof a *-nother there oes the modesty...) scoop for the +I website, as all most of us have ever seen of these cases, is one picture in erryatfield's fine books. hanks aain to im for the pictures Moen.

Big Base case to the left, $port $cout right.

ote (atmain bearing boss.

%nother view. ote that the major difference inthe mounting points seems to be just the lower

rear boss' new rear engine plates will solve this.


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+lose up' BB drive side main bearing boss. $port $cout main bearing boss.

Fear view' BB on the left. Look at at that fatsnout for the d5s bearing... ote also shallower

cam case on the BB.

%gain BB left' look at the way the lift cavity ismoved inwards, and the beefed up mainbearingarea @not partially cut away like the stock cases,

rightA.

+lose up of the BB cam area. Lift cavity moved

inwards making cam case shallower.$ame view of the stock cases.

Drive side cases, BB left. ote sump andflywheel scraper @and beefy bearing bossA.

+am side view. BB left.


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Interior view of BB cam side case. ote how

nice fat things are.

$ame view of stock cases. *his is what thefactory gave us to play with instead of what you

see to the left of here....

0ar'at" B!g Base $cout eng!necases, By! Lyle Landstrom

*he real reason for the Big Base engine cases is the same reason that I switched to ridingIndians in the first place. *hat is, in my opinion, a motorcycle should be a motocycle and not atwo wheeled car. (odern bikes lack the light weight, lines, and most importantly, feel, of bikesgone by.

Being an Indian and a foundry enthusiast, it was natural that I combine the two. %bout ? years

ago I started making parts in my garage. (y purpose was to have some 7neat7 parts that noone else had. %t about the same time, I started trading some of my homemade parts andfoundry services for items I needed. *he main goal however, was to make stuff for myself, getbetter at my craft, and build my garage up to the point where I could really do something. *hattime is now.

*he Big Base project started out as a simple inquiry on the irtual Indian list. I had thefoundation for a $cout project which included a set of wrecked cases. I thought it would beeasier to manufacture a new set rather than repairing my own set. I also thought whatevercases I made should incorporate some improvements. &ence my inquiry.

/im 0all responded to my inquiry by sending me a copy of the original factory drawings forthe right case. *his was more than anyone could have asked for. I took these drawings and

converted them to +%D so I could manipulate them to facilitate the pattern making. I couldalso edit the +%D drawings without destroying the originals.

0ithin a couple of weeks after my inquiry, the Big Base cases became a project on the irtualIndian magaine. %t the time I thought I really didn"t need the hype as it was a serious projectbut the intent was more for my own purposes rather than any group effort with intentions ofmass distribution. /im sent me the drawing with the understanding that it was a 7grassroots7effort. It is my intention to keep it this way. I am not a big corporation, nor do I intend onbecoming one. I"m 7/oe Blow7 in a garage. If it was my intent to be making money, I wouldn"tbe into manufacturing, I"d be into distribution.

Because of the project listing on the irtual Indian magaine, several people have responded

with suggestions. Damon $trub had some concerns about the rear motor mounts. *his hassince been confirmed. /im 0all suggested bigger cam bosses for bearings rather than

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bushings. (y own cases are blown out at the bottom and the front and rear motor mountareas are broken. %ll these problems will be fi#ed with the new cases.

It is not my intention to produce some 7fake7 cases and rip off the Indian name or cheapen the

few Big Base $couts in e#istence. (y intention is to build a set of cases that will sustain highspeed high rpm modern Interstate long distance riding. *he cases will be similar to, yetdifferent enough to be noticed, from the originals. I could argue that once these cases arebuilt, original Big Bases will be worth even more, not less.

ow that this is a ongoing official project, my steps are as follows!

4. 1roject +onception9. $olicitation of iews2. -inal Design6. 1attern (ethodology?. 1rototype +astings

. 1rototype (achiningO. 1attern %djustmentsH. -inal 1roduction +astingJ. -inal 1roduction (achining

%ll of the steps above will be in house. *hat is by myself, or members of the list. I"ve done allthe +%D work and am starting on the patterns. I also plan of doing the foundry work in mygarage with certified 2? aluminum. I"ll then send the castings out for heat treating. /im 0allhas agreed to machine the first set of cases. *his is no small effort on his part.

%t this time /im 0all has been sent 2 prototype cam covers. *he covers utilie the castaluminum oil pump and also are deeper for double lobe cams. If regular cams are chosen, thee#tra material can be machined off. /im is in the process of doing the prototype machining onthese covers. *he pattern making and casting is covered in another article in this month"smagaine. %lthough the cam cover article was written from a lighthearted perspective andwas a sort of 7bang up7 job, I can assure you, the Big Base 1roject is serious business. I haveinvested too many hours at this point to quit or do a half ass job. *he drawings /im sent meare much more readable than the cam cover drawing I had to work with for the cover pattern.*here will be less 7slop7 in the case patterns.

(oen asked me to write this short item concerning the Big Base 1roject. *his also serves thepurpose of answering questions and dispelling rumors that might be out there. I"ll keep (oenposted as to the progress of the patterns and subsequent castings. (y regular job is going toget busy as the construction season is about a month away and I"m going be working longhours. 0hen this starts I"ll need to quit the list as I cannot handle the long working hours

combined with a hundred email messages a day. I"ll need my off time to complete thepatterns. *he patterns will take a good month per side of part time work to complete. %lthoughsome operations for either side will be simultaneous.

I would like to thank everyone for their questions regarding these cases. 8nce the patternsare complete and the first few are machined, 0e"ll take a step back and see where it goesfrom there. It is my intention to trade raw castings for whatever. But if there is enoughdemand, I might see if there"s a ++ shop that will undertake a batch of them. %s far as thecasting, I can handle whatever demand there might be. *his is not a corporate effort, yetmaterials, heat treating, and machining do cost money.

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(/

ere' s the oriinal +I article on the 0i 0ase cases *use your browser's !back! button to et

back here)

Related Articles in the April VI:

DIY Casting & Pattern Making

The Four Cam !stem

Tall Fin racing heads

(am cover.

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1rototype cam cover ready for machinin.

T"e 1-&am $ystem% By /im 0all

During Indians last fling a small batch of 6 cam big base racing $cout where put together byDick Gross and ridden to success by Bobby &ill. *he 6 cam machines where a system thatincluded the whole machine.

*he chassis was based on the 6H style factory racer but was retubed with thin wallchromemolly tubing and further lightened by drilling holes in various locations and pluggingthe holes with aluminum slugs. %luminum fork links as well as motor plates where used.Gross painted everything on his machines to disguise what he had done. *he handlebarsrisers where from the vertical $couts and mounted with an aluminum plate to the forkcrown.

Light weight machine oil was used in the hubs to cut rolling resistance as well as 4; weight oil

in the primary and transmission. *he front wheel was a simple hub and the rear wheel carrieda sprocket to keep weight down. In talking with the son of the Indian dealer here in Denver hesays he can recall seeing &ill at a race in ansas. &e recalls Bobby spinning the rear wheelas the machine was on a stand and that he and his father could not believe how long thewheel kept spinning on its own. *he tanks where the factory narrowed 6H tanks, and themachine used a tachometer driven off the front cam, the tach was from a orton. *he saddlewas from a &arley F.

*he motor was unique in that it still had the two camshafts, but each shaft had two cam lobes,one for the intake valve and one for the e#haust. *his required a thicker cam cover in order toaccommodate the e#tra cam gear. It also required a different e#haust valve lift, lift shafts,cam shaft shafts and pinion gear arrangement.

*he set up essential used a factory cam to which Grosses own unique cam lobe was pinned.I"ve seen one set up where he was using a factory $avannah came run backwards with hisown lobe pinned to it. &e used a factory Bonneville lift with a spacer braed to the side of it atone point. &e also hand made his own lifts with different center to center lengths.

*he cases where big base with ball bearings everywhere, and with a steel sleeve pressed into the drive side to carry the ball bearings. &e alsomachined steel cups and pressed them in to the cases to carry the ball bearings for thecamshafts.

*he cylinders used a 45H over sied inlet nipple braed in to the cylinder. *hey also had a 45Hover intake valve. *he e#haust valve was the standard sie. *hey used the m3?2 4 459 &Dcarb with the bombsight venturi.

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Ignition was by magneto. *he oil delivery to the motor was adjusted by pressing a drilledorifice in to the back of the aluminum oil pump directly in front of the pinion shaft. Differentsied holes where used. %ll in all it must have worked well as they sure did run.

Lyle has cast up some of the deeper covers for use with the aluminum pump. *hey have to bemachined. I have bits and pieces of one of the 6 cam motors, cases, oil pumps, one half oftwo different cam set. *he missing bits, outside of the valve lifts, will be easy to do. %t thatpoint there will be a four cammer running again in addition to the two that already are.

*iming chest of the 63cammer

Drive side bearing housing

Drive side housing, e#ternal

ut for bearing housing, the way Gross did "em


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Big intake nipple left, stock right

$'ort $cout Rac!ng Heads% By /im 0all

*hese heads are the early straight fin style 7tall fin7 racing heads as seen in erry atfield'sIllustrated 0uyers' 2uide page ?.

*he pattern assembly is at a local foundry at this moment. *hey will repair the actual patternsas needed and do a mold at that point. 0e will then inspect the mold and make a decision asto tune the mold up further or proceed with castings.

*he castings will be of a 2? t3 form when done. I have no idea as to cost yet but do note#pect to retire from this project either. *he foundry owner seems to be very enthusiasticabout this project. &e walked me through his entire operation from start to finish, kind of fun. Iwill keep the group posted as things proceed.

%t this point I have recorded interests for O sets of heads, not including myself or others thatare not wired.

If you are seriously interested in a set of these heads, please get in touch with me at thisemail address! fasstjimQaol.com or order a set on the I Buyers2 &lu# pageE .

mailto:[email protected]:[email protected]://virtualindian.org/3bc.htmmailto:[email protected]:[email protected]://virtualindian.org/3bc.htm


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homemade motorcycle parts

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