TriTon!

[grandpaul]

I'm SLOWLY building a TriTon (Triumph big twin engine in a Norton "FeatherBed" frame) since a good friend of mine sold me a spare frame he had (what started out as a sad story turned very happy for me).

I have so much STUFF crammed into my shop / garage / storage, that it wasn't hard to piece together a photo mockup:

[philipbarrett]

Bet them pipes are loud - as in "hey Mr. harley dude, you can save lives but I can resurrect!"

You have some drool-worthy stuff on your site, especially that 850 Commando. Ape hangers & a banana, that poor bike must have hung it's head low.

[grandpaul]

That barely-rolling mockup photo was taken in September 2010; since then, I've acquired a few really cool bits that will serve to better identify it as an upper-tier build, rather than a slapped together monstrosity.

As it stands now, and will likely firm up as, these are the specs:

ENGINE
1966 Triumph T120R Bonneville 650 lower end
Hardened 3134 profile cams (ionization nitrided)
"Heavy" crank (full width flywheel profile)
M.A.P. Aluminum big-bore cylinder
M.A.P. 10.5:1 lightweight pistons; ceramic coated tops, teflon coated skirts
Mildly dressed & cleaned '64 "small port" head
Kibblewhite Black Diamond valves & guides, titanium collets & keepers
M.A.P. belt drive primary & clutch pack
5-speed tranny cluster from Kenny Dreer (ex Vintage Rebuilds)
Amal MkII 36mm carbs with K&N air filters
Tri-Spark electronic ignition and dual-output coil
2-into-1 BUB exhaust headers with smallish carbon fiber can
Mirror-polished engine covers with allen-head fasteners

CHASSIS & RUNNING GEAR
1966 Norton 650SS "FeatherBed" frame & swingarm (powdercoated)
(The FeatherBed frame is legendary for it's superb handling; it brought about the famous motto "The Unapproachable Norton")
Suzuki GT550 Front end with progressive springs
Four Leading Shoe front drum brake system laced to 18" Excel aluminum rim
My own design swingarm spindle upgrade to hardened 3/4" stock turning in sintered bronze bushings (instead of fixed metalastic bushings turning on 1/2" bolt)
Rebuildable, tuneable progressive rate shock absorbers
Matchless G15 rear hub / brake, laced to 18" Excel aluminum rim
Avon AM RoadRunner tires

CYCLE PARTS
Lyta Sprint fiberglass gas tank
Norton Manx style seat
Early Norton Commando central style oil tank
Clubman clip-on handlebars
Tarozzi adjustable rearset footpegs
Lockhart oil cooler w/ thermostat
Steering damper

I'm sure I'm missing a few details, but the engine is totally torn down, head is done, it will get all new gaskets, bearings, bushings, seals & o-rings, and a thorough soda blasting of the cases before they go back together.

[philipbarrett]

How'd a Brit end up in Laredo?

Then again, how'd a Brit end up in Dallas...

[grandpaul]

I own 80% of the Brit bikes in Laredo. As far as I know, there are only 6 others (I have 24).

What I have learned in 35 years, is that there are Brit bikes EVERYWHERE! (you just have to look hard)

[RedPill]

I thought this was going to be about going 300 MPH.

[grandpaul]

For anyone who is interested, I'll continue with the back story.

It all started with my friend, Mark, paying for a featherbed frame that never arrived. After he found another one and received it, the first one landed on his doorstep! He offered the rougher of the two to me at a price I couldn't refuse-



This was the engine I had sitting on the shelf in my storage room with a couple of others-



My initial plan involved this pair of vintage Ceriani racing forks with Arces yokes-

[grandpaul]

Slowly, over the last 2 years, I acquired:

-A 5-speed cluster complete with shafts, forks, quadrant & camplate from Kenny Dreer (the guy that tried to resurrect Norton here in the U.S.)



(that will plug into the 4-speed box with very little effort)

Scored a nice Lyta Sprint tank (modern resin fibreglass) on e-bay-



Found an e-bay deal on these hydraulic clutch conversions that have a tiny slave cylinder with a stub of cable attached to the piston. You screw the slave into the clutch cable abutment at the tranny cover and that's all there is to it! Sounds like a nice trick bit for this bike. (no photo, sorry)

Also scored a Suzuki 4 Leading Shoe drum brake on a front wheel (it'll get unlaced and sent to Buchanan's to be laced onto an Excel shouldered aluminum rim-



If you've never see one of these brakes, it has twin leading shoe setups on BOTH sides (4 shoes total). This bike will stop as well as it goes.

[grandpaul]

My preliminary styling excercise (pipes will change, as will front brake, and it will have lights)

[grandpaul]

The "swingarm spindle" on early Norton featherbed frames were nothing more than a 1/2" bolt through the two rear frame web plates, with the swingarm pivoting on two metalastic bushings pressed into the main pivot tube.

That meant that all the swingarm's pivoting and loading forces were transmitted through a non-lubricated fit between two bushings less than an inch long, and a 1/2" bolt, to the mating faces of that 1/2" bolt at either end where it met raw steel plates. Nice, huh?

My initial concept for an upgrade was to fabricate two 3/4" O.D. half-spindles that would be bolted to the frame webs, insert two 1-1/2" long x 3/4" I.D. sintered bronze (lubricated) bushings into the swingarm, and through-bolt the whole assembly for security using the old 1/2" bolt.

[grandpaul]

After some back-and-forth with friends on other forums, I morphed the design into simply installing the bronze bushings in the swingarm, welding a plate to one end of a piece of 3/4" hardened bar stock, threading the other end of the bar, and fabricated a companion capture plate for the opposite end of the shaft with a Nyloc nut to retain it.

Thanx to my custom knifemaker friend, Enrique (who did the MIG welding and showed me how to use his lathe) here are the results- (Note the lubrication port (1/4" bolt at top) for 140W bearing lube)-







The assembly takes two bronze thrust bearings (with captive o-rings to keep the lube in check) between the swingarm face and the frame plates.

So, with my retrofit kit, (I've got 6 of them set aside now), the swingarm forces are transmitted through a lubricated, precision fit between the 3/4" bar stock and two 1-1/2" long sintered bronze bushings, to a 4-bolt security fit to the frame webs AND the 3/4" diameter precision fit between the spindle and frame plates, all held in tolerance with a 3/4" hardened Nyloc nut that can be precisely shimmed and checked at the thrust washer interface. "A bit" of an improvement...

Note to any featherbed purists on board: If you believe I've destroyed the legendary handling of the frame with this modification, I'll only agree to disagree, agreeably. I don't believe that adding rigidity and precision to the swingarm's connection to the frame distracts from any aspect of structural performance of the assembly. If you believe the inherent flexibility in the original design somehow acted on the original assembly to moderate excessive forces imposed on the relatively mild tubing materials and small diameter interface hardware, to produce the legendary ride, you don't have science to back you up.

[philipbarrett]

keep it coming...

[grandpaul]

Okay, back to the assembling of parts.

By Feb 2011, I had the frame & swingarm powdercoated; spindle end and opposite plate will get coated later-



New bearings, seals, gaskets, valves & guides; some parts not for this bike-



This is a set of engine mount conversion plates that took quite a while to get from the Motherland-



After fussing with the mock-up, I've designed some changes and will be fabricating a few sets for sale in the future.

[grandpaul]

Preliminary mock up of the mounting plates-



Top steady needs an adapter plate to bolt to the rockerbox/headbolts; the little chunk of angle aluminum it came with AIN'T GONNA DO!



One slightly used Tri-Spark electronic ignition unit, for about 1/4 the price of a new one!

[grandpaul]

June, 2011

After the sad passing of my vintage roadracing mentor and Britbike friend, Malcolm "BritBodger" Dixon, I was asked by his next-of-kin to assist in liquidating his estate; we did our best to sell a house full of nearly 50 years of Britbike riding, collecting and racing, at fire-sale prices. Several thousand dollars in proceeds were donated to the BMOA Houston, and AHRMA, Malcolm's two favorite associations.

Malcolm's nephew, Paul, insisted on letting me keep a few bins of spares that remained after the sale; among the cool stuff in the bins, that will go on the TriTon, were:

- matched pair of new Amal MkII 36mm carbs with K&N filters
- slightly rusty but not dented 2-into-1 header
- Tarrozzi rearset footpegs (one broken, one cracked, but easily welded up)
- very slightly used M.A.P. alloy big-bore cylinder with lightweight pistons (no rings, but easy enough to match)
- used dual lead ignition coil
- used Lockhart oil cooler setup & cylindrical oil filter rig
- various crankcase & rockerbox vent fittings
- set of slightly used lightweight valve spring collets & keepers
- set of slightly used MAP clutch plates
- M.A.P. alloy clutch pressure plate
- various chunks of aluminum plate stock that I can use to fabricate brackets from

There was so much stuff I could have used, heaps of stuff I'd love to have, and some pretty fancy go-fast racing parts; but my goal was to get as much of it out to the membership as possible, so my gleanings were from the leftovers! I really looked long and hard at several partitioned drawers full of whitworth hardware that I could really use right about now; one guy got the whole lot for like $20.

So, I will formulate some sort of tribute to Malcolm on the bike when it's done. I hope to do him justice.

[grandpaul]

July 2011, finally got to a point where I could spend some time tearing down the tired old '66 Bonneville engine-



Jugs took no more than a tap or two with a rubber mallet to pop free-



Pistons looked terrible, very badly scuffed-

[grandpaul]

Cylinders were not too bad at all, no scars or corrosion (although these will go on the shelf for some other project)-



Exhaust cam followers were kinda rough, not too bad (I have a better set on the shelf)-



Ditto with the intake set-

[grandpaul]

Looks like the rods are not too bad off, but they've been oil baked at least once and partially cleaned, or so it would appear. Anyway, I've got a better set of rods, too, so these will also go on the shelf-



Primary was actually quite clean. I have a much nicer alternator that's going in-



Entire chain drive primary, clutch basket & plates including pressure plate will be replaced with MAP stuff-

[grandpaul]

The stack came out in two glazed-together lumps with one curious loose steel plate in between (typical stuck Triumph clutch from sitting)-



Many a hapless Triumph owner has been taken by suprise by a set of stuck clutch plates! \

After sitting a while, the clutch doesn't disengage by simply pulling in the lever; so the poor unsuspecting victim finally kicks the beast to life, pulls in the clutch and grinds it into first gear, whereupon the bike launches off on it's own (typically straight at the nearest expensive car, set of sliding glass doors, or cactus garden). Hilarity ensues for any lucky bystanders, with the possible exception of the secondary victim who happens to end up in the wayward bike's path.

This can be especially fun on disc-brake models, as the end of the joyride typically does not involve brakes in the amusing aftermath.

[grandpaul]

..okay, I'll throw in the requisite "DON'T ASK HOW I KNOW THIS!"