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Discussion Starter #1
Pardon me if I am going down a path already traveled, in which case someone please just direct me to the old thread. But I have looked back quite a way and don't see this topic, although intriguing parts seem to be covered in different threads.

Looking back at the old threads has made me very curious about what folks here would do if they could build a Triumph from the ground up, using Triumph parts. I remember one comment that Triumph never quite got it completely right, as in they never got all their best stuff on one model? What is the best frame to use and why? What engine? What cams ? Long rod or short rod? Why? Light '66 flywheel crank? What carbs? Head? Suspension? Tires? You get the idea.

Then, suppose you could use after market parts. What mods would you use? Electronic Ignition? Mikuni carbs? Exhaust system? What would you change first? What is most cost effective?

Since I am in the project planning stages, I am really interested in what you all have to say. If one of my projects (as expected) will be a metisse, I would like to have the best one I can do, as opposed to one that just runs. (Although that may be the first incarnation.)
 

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The ultimate Triumph is the one that makes you happy, whether its styling, speed, nostalgia etc. Mine might be a 70 Daytona 500, silver and purple as that was my first bike. Or a 64 Bonneville as that was the year I was born. You get the drift.
 

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when replying to this topic, please post Car-Toon -style drawings with a flaming rear tire and your tongue lolling out backwards while your eyes bug out on stalks.
 

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Discussion Starter #5
WOW. First philosophy, then Ed "Big Daddy" Roth. What next?

C'mon GPZ. A stock '70 Bonnie? Surely you can think of things Triumph did better in a different year that could be borrowed to improve the bike.

For example, figure on doing more running around town than backroads. How about a '65 frame with a '69 swingarm and later internal spring forks as a base?
 

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The ability to use aftermarket parts opens up a HUGE universe. But, to keep it simple (relatively)........Any sidebag oil tank frame.....64-70, but I would select a 63-65 front frame, 68-70 rear frame, 69 cases, 68 crank, heavy stock rods, Routt 750 kit w/MAP forged 9.5 : 1 pistons, 750 cam pinions, 750 oval port oil pump, JOMO 15 cams, 500 tappets, tubular special pushrods, ground and polished rocker arms, 77-on five speed gearbox, MAP belt drive, Sparx or Lucas 3 phase alternator, Borrani rims, Buchanan's SS spokes/nipples, Westach electronic tach, Smiths speedo, 1978 blackface, 72 Bonneville bolt on manifold head with push-in exhaust adaptors and inlet adaptors for 32mm Dellorto carbs, 71 rocker boxes, 74-on rocker shafts with extra o-ring grooves lathed in, 69-on tappet blocks with opened up drains, late pushrod tubes, Black Diamond valves, Ampco 45 guides, alloy valve spring retainers, hard anodized alloy rocker buttons, allen tappet adjuster and alloy locknuts, rocker spacers.
Alloy engine and pass. peg mounts, Ceriani dual lug road race forks, Ceriani or Fontana 4LS brake, Alloy replica of stock rear hub, Works perf. 13.5" shocks, alloy handlebars, Forged Magura levers, Tommaselli throttle, Alloy fenders, Stock exhaust system, C model headlight and footpegs, custom Belden teflon wire harness.........and a lot more......

[ This message was edited by: Mecchanica on 2006-12-01 19:31 ]
 

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Go with a single carberator.Avoid double downtube frames made in @1960 for preunits. Double downtbes for units are ok. Hop it up at your own risk. I detune mine for easy starts and lower octane requirement, dependability no pinging. or preignition.
I also do away with all of the wiring and rewire the simplist way for function . If you go for factory original wiring good luck. You will have to depend on a harness made from ?.
Rubber mount coils, if you use them. and the haead and tail light,. I use rubber grommets and self locking screws..

I also run a magneto and that keeps the rest of the electrical system seperated from the ignition.

Most of all, think things trhrough and have fun. If things get heavy, just cool it for a few days.
 

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Discussion Starter #8
"The ability to use aftermarket parts opens up a HUGE universe."

Absolutely, which is why I said start with and all-Triumph best metisse and THEN think about aftermarket stuff!

Why did you choose the 63-65 front and the 68-70 rear frames? What swingarm? Which Triumph fork and front wheel/brake would you choose? Why?
 

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:gpst:

You've opened a whole big can of worms, here, Oldbonnie. And I'll bet everyone on this forum has a hook to bait 'em with!
 

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ultimate depends essentially of how you plan to use the bike.red59 and mecchanica are obviouslylooking in different directions and they are right both !!
personally i'm more "red59" inclined but the "mecchanica"
option is very seducing too in an other way (and much more $$$$$$$ too).
you have too bikes:make the tr6 a red59 dependable smooth
bke and make the t120 a road racer with all the expensive and the high quality gofaster items as proned by mecch...so you'll have ,not the best of both world ,but the best in both worlds!!!patience and high money is all you need...
begin with the tr6,cheaper and quicker, so you can enjoy soon the real thing that counts:riding a well fettled triumph!!
ben
 

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All magnesium cases in a '70 frame, with Brembo disc brakes, Routt big bore kit on 650 lump, Nourish head with a weber injector, megacycle cams, Hunt magneto, 3-phase Sparx alternator, "buckhorn" bars, magura levers, Akront rims, Dunlop universals, 2-1/2 gallon tank with rubber kneepads and '70 style emblems, Ceriani forks, Koni shocks, '68 crank with carillo rods, barnett clutch on a dry belt, 5-speed Quaife box, 2-into-1 Dunstall Power pipe, '67 style tail light, '70 grab bar, stainless polished fenders.
 

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Discussion Starter #12
Bonjour Ben. Comment allez-vous?

My Trophy is closer to original and probably the better candidate for restoration to original condition. The Bonnie is rougher and non-matching, so a better base for a hot-rod. I will probably try to get the Trophy road-ready by spring, and start collecting the parts to make it as original as possible. By the time I'm ready to do a full restoration on the Trophy, the Bonnie ought to be on the road. And I am thinking the Bonnie hot-rod will be an ongoing project, with modifications made as I go along. For example, I will probably be starting out with a 4 speed 650, but eventually will hopefully wind up with a 5 speed 750.

For my situation, most riding would be around town, with an occasional short run on the expressway, and an occasional all day ride. So I would lean more toward an urban street fighter

But what would you do if you could build a Triumph from scratch using the best original Triumph parts? More interesting, why would you choose particular parts? Of course your riding conditions and riding style will affect your choices. The bike you came up with would probably be different from the bike Mecchanica would build, but that doesn't mean one is necessarily better than the other. Hopefully it would be better for you.

Then having built your all-Triumph "best", which non-Triumph mods would you make? And most important, why? I'm assuming some common sense would apply, and not everyone has a money tree in the back yard, so mods would need to be cost effective. But even "cost-effective" depends on how and where you ride and your own preferences.

For example, I'm starting with '66 models, so I will certainly use the '66 frame to start. If I had my druthers though, for my ultimate Triumph I might choose the '65 frame because of the steeper head angle, and the '69 swing arm because it is stronger. But if you were more cruising more and did less town riding, you might choose a different frame. I am curious to know why Mecchanica chose the frame/subframe he did; the criteria he used might make me re-think my choice. (And when I get done with frame/chassis questions, I have a bucket of engine questions for him too.)

For my ultimate Triumph, I would use later model internal spring forks, and the DLS front brake. Why? I like the looks of the later forks, and they work better. (I bet someone even has a preference among the later model forks; I don't know enough about them to know if some are better than others.) While the disc brake probably makes more sense than the DLS from a strictly performance standpoint, I like the way the DLS brake looks. On the other hand, if one was substantially lighter than the other, I might have to go with the lighter one.

To me, getting the bike as light as possible is important. Light weight generally means better performance and handling. I spent many hours when I was racing trying to figure our how to make my racers lighter. (I bet I had one of the lightest CMFs on the track by the time I got done with it.) So given the choice between parts of similar functionality, I would be inclined to choose the lighter one.

So c'mon Ben. What would you use, if you were building from the ground up, with a free hand?
 

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The engine guts I described are pretty much what I have been running for 11 years and 85k miles in a MOST roadable engine. The Bonneville head is the biggest difference, and I specified the MAP pistons, because the Morgo AE pistons I am running in my Routt kit are harder to get, at .060 over.
I'd use the early unit frames because of the 3 degrees less rake, shortening the wheelbase and quickening the steering....also moves the center of mass slightly forward. I would use the 69-on swingarm (or T150), as they are stiffer. I selected the late rear frame because I like the easily removable sidecover which doesn't crack and the early frames used a solid mounted oil tank, and I prefer the rubber mounts on that.
The cams I use have more overlap than the stock ones, lowering the effective pressure in the cylinder at low rpm, thereby reducing the tendency to ping when accelerating from lower rpm even though the bike runs the higher compression pistons, and the five speed is effectively a closer ratio four speed with an overdrive when used with the high final drive ratio, allowing you to keep the engine revs high enough to minimize pinging without overrevving or getting buzzy. Keeping the mixture a tad on the rich side, enough to grey the plug electrodes, but not enough to foul the plugs, also keeps the bike tractable, and heat is a concern here in Hawaii.
I didn't go into detail about the modified oil system. The pressure relief valve won't be in the case anymore. The stock setup dumps excess oil into the timing cover and then back to the tank. This provides most of the lubricating oil for the timing pinions. It also provides drag and doesn't do anything to cool the hottest part of the engine, the head or cylinders......Sooooo I plan to fit a Morgo gear oil pump and then to make an oil manifold. The oil pressure relief valve would be mounted in the end of the manifold and high pressure oil would be fed from the plug that replaces the valve in the case to the manifold via Earls ss/teflon hose. This hose will not pass oil until the pressure in the main oil gallery of the engine raises to the 85 pounds for the engine, then, as the stock bike does, it begins to leak off enough oil to keep the pressure at that level. The oil that bypasses the valve goes into the maifold which feeds the machined Barnett valve adjusting caps. In the end of each banjo bolt, on the inside of the cap, is a Mikuni main jet. This allows me to easily adjust the flow of oil to the valves....more on the exhaust, less on the inlet. The drains in the tappet blocks are drilled larger to allow the additional oil to drain back to the sump, also providing more oil for the tappets and cam faces. The larger drain holes also allow for better breathing from the rocker boxes, reducing leaks.....theoretically. There is another pressure relief valve in the other end of the manifold and when the pressure reaches 95 psi in the manifold, it begins to bleed off oil to a line that feeds back to the timing cover, to lube the timing gears and dispose of the excess oil in the system. On the way back to the tank, the oil passes through a filter/cooler. A similar system works pretty well for my Thruxton, except they use two oil pumps. I thought about that, too. Originally, I was going to fit a second oil pump to the end of the exhaust camshaft, replacing the tach drive, which I don't use. The first iteration of this was to make a system for the gearbox lube, to keep it cool and filter metal bits out. But I think that is probably gilding the lily. A few of the strong little Neodymium/Iron/Boron magnets in strategic locations would likely do as well. I had a couple of them stuck on the back of the oil tank which are now stuck to various bits of the Thruxton oil system, including the filter can. They won't pick up little bits of nonferrous metals, but I suspect they are less of a danger than the hard steel bits.
Now, if we are talking stock forks, certainly the late shuttle valve steel forks would be my first choice, along with a lightened Iron hub DLS Triumph/BSA brake. The only other choice would be the disc brake setup. I think I could bore out the lower legs and the yokes enough to fit 35mm Ceriani stanchions and guts, or perhaps Betor. Then get either the Lockheed calipers or go large and get some four pot billet items, drill the discs, fit a 13mm bore master from those French guys or go cheap with the Grimeca. If we can switch discs, then the 12" floater would go on the list. A fork brace would be a good idea for a single disc setup. EBC brake pads. Earl-s -2 hose.
The target is a 350 lb. reliable roadster.....kinda like my 68, but with more Bonneville power. I've been running a TR head with 32mm Concentric, and have been ok with the power delivery vs simplicity. I would like to try out a single 34 or 36mm Dellorto pumper carb and do a dyno and riding comparison. Well, I DO have an extra TR6 head.........
OH....If they become available again....I'd get one of the Aerco ten bolt 750 cylinders for long rod engines and fit the 10 bolt Bonneville or TR head. Nag Bill Getty at JRC Engineering to get them made again.
Oh, and some years ago, I had a set of Carrillo-style beam rods in ALLOY with steel caps and replaceable bronze bushes. I don't know who made them, but they were just GREAT. Maybe I could nag Carrillo to make them now, with a little help.
 

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Discussion Starter #14
Red-

I can see you value reliability and tractability. The rubber mounting of everything possible makes sense on the old vibrators. I thought about a customized wiring harness. Do you run a separate ground wire or rely on the frame? And the magneto setup has some pluses too. I like the idea of separating ignition from other electrics.

I bet you will think of a couple of other things you would choose too. I expect my opinions will be affected by other ideas that folks will hopefully be contributing to this thread.
 

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Discussion Starter #15
GPZ, I never heard of a Nourish head.

Why choose the '70 frame? And I'm interested in the Triumph pieces you would choose for the all-Triumph version. What forks and front wheel?

Why the '68 crank? Why the '67 taillight?
 

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The 70 frame has removeable front mounts, which makes it possible to remove the engine intact. But that also adds a touch of weight. And as often as I plan to remove engines, it's not an issue. Plus, I take them apart in the frame to get them as light as I can. Bum back.
68 crank has a light flywheel and two timing notches...actually, there are Mark 1, 2, and 3 versions. Some of the 68s had a second timing hole in the front, as per the BSA and Triples. They dropped that quickly, as it was pretty much unnecessary. Handy, though....easier to get to than the one behind the cylinder. Plus, like the 66 and 67 which also had light flywheels, the 68 was balanced and came with the thicker and stronger late model con rods.
Nourish Racing Engines (England) makes an 8 valve top end, cylinder (of up to 800cc on a unit engine.....bigger with their stroker crank), four valve/cyl. head, pushrod covers, rockers and shafts and a valve cover. Plenty of power, but kinda fugly. Can't use any stock parts, either, so there is the possiblility of downtime if you have a problem.
67 taillight because it is the most beautiful one on any Triumph and better than almost any on any bike. I lucked out, my 68 left the factory with a 67 taillight. I plan to put one on my Thruxton.
OH.....and folding C model rider pegs and C model small light with a high zoot H4 conversion.

[ This message was edited by: Mecchanica on 2006-12-02 15:39 ]
 

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Discussion Starter #17
It is going to take a while to digest all that stuff, Mecchanica! Thanks for the input.

Starting with the chassis choices: I didn't realize the '63-'64 frames had the steeper head angle too. The '68-'70 rear frame makes sense for the very reasons you mention. Which years were the shuttle valve forks made? How would you lighten the DLS front hub? Do you know if the end result would be lighter or heavier that a disk brake front end? If you stick with Triumph stuff, I guess the front fender and braces would be dictated by the forks. I would give some thought to a fork brace that would also serve as a fender mount; it should be possible to get a setup that is both stiffer and lighter than stock.

As for the engine stuff, I want to dig out my manuals and study up before I start asking questions about the modifications to the lubrication setup you recommend. But why did you choose '69 cases? Why the '68 crank? I know my '66 has a lighter weight crank than some, and that crank lightening was a common hop-up back in the day. What do you mean by the "heavy" stock rods? I gather you prefer the long rod setup as opposed to the later short rod 750s. Why? Did you pick 750 cam pinions because of the weight? What Triumph cams would you use? Are the 500 tappets lighter? Any other good choices for valve train items among production parts?

Wheew! Enough for now. I'm sure I will have lubrication questions once I have a chance to study your system.
 

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Olde: For the "all Triumph" '70 Bonnie, I mean AS ORIGINAL, like NEW. As with everyone else's opinions, mine is the correct one - '70 is the best.

Mechannica knows his stuff on what's what with Meriden Triumphs. If you've read three or four of the better background books, they start to concur on a great majority of significant points. The exact type and proper location of a specific decal, or the "proper" routing of the clutch cable on a '69 TR6 is insignificant to me.
 

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ok..let's do it!
motor:750cc conversion with 70 cams,dynamically balanced crank,morgo rotary oil pump,norton type oil filter on the return line before the the T to the head, a small oil cooler switchable for summer/winter,points and no electronic ignition,a cylinder head shop(england )head rebuild with the best valves and guides available, some head porting,kedo type tappets adjuster(they make it for the 500 xt/sr not for triumph but i think it's possible to getit done;it's only a question of thread),probably a better alternator and a battery eliminator,a five speed gearbox with a longer final drive, a belt drive dry cluch primary,two 30 or32 mikunis and that's all for the moment.
cycle parts:a 70 frame with the 70 tls brake ,progressive fork springs,alloy mudguards with a discrete fork brace under it,a enclosed rear chain(yes!)which doesn't exist yet,a 4 gallons fuel tank with the 68 paint scheme and the marvellous parcel grid(very usefull feature!!)
well...
to answer to you in french :je vais trés bien ..et vous?
make sweet dreams ..here it's 2 oclock in the night
ben
 

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i had a good night and i remind a feature to add to my dream bike:nicasil alloy barrels..harris made them but the threads stripped at light speed but they can be redone and overhauled by fitting inserted steel threads(am i clear?)
less weight, better cooling,les piston slap what else?
ben
 
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