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[4]

Triumph Bonny

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th62

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Aug 22, 2014
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#1
I bought this bike around 1993 I believe and set about fixing it up to my liking. First pic is as I bought it, second is in its second incarnation and third, fourth and fifth pics in its final incarnation. I used this bike daily in the Territory with the shotgun pipes, it was loud - very loud but I never had problems with the law. In its final incarnation I had moved south to Adelaide and also used it for daily transport, to please the law (and the neighbours) I added mufflers. Along the way I made many minor mods:

Wheels were disassembled, hubs polished and re-laced with stainless spokes. Lower fork sliders, crankcase halves, rocker covers, carbs, air cleaner, rear brake mount and so on were all mirror polished. Seat base, tail light bracket, sidecovers, battery box, air cleaner were hand beaten ally. Side covers, guards, battery box, reservoir and so on were all mounted via rubber grommets for which I turned up dozens of positive stop ally nuts/bolts. An oil cooler and oil filer were mounted on the front downtubes via a polished ally bracket I scrounged from a floor polisher, the oil filter housing was a Norton unit which I also polished. An ally bracket was shaped for the under the seat electrics to which I mounted an early model zenner, a Tandy rectifier and a master switch. A rocker switch for ignition was mounted on the left sidecover and I then rewired the whole bike. All fasteners were polished S/S allen heads, the pipes were 2" shotguns to which I added internal baffling and later mufflers. I also turned up a couple of ally footpegs, an ally fluid reservoir and lots of other bits and pieces that I can't remember now. Internally I reshaped and polished the gearbox camplate, added Barnett plates, lightened and polished the rockers, changed the cam timing, polished the inlet tracts, piston crowns and combustion chamber and had the crank electronically balanced. The bike was painted in gloss jet black and the seat covered in black patterned vinyl.

I did all the work myself except for crank balancing. It won best Triumph at the Darwin European Bike Show in the late 90s. I had many plans for this bike: alloy barrel, mag, mikunis, Boranis, etc, but I stripped her down for the trip south after being medically discharged from the defence force and never had the $$ or the inclination to put her back together so sold her as a basket case.

1.jpg 2.jpg 3.jpg 4.jpg 5.jpg
 

th62

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Aug 22, 2014
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#2
Funny thing about tuning the Triumph, it ran great if tuned manually by running on one cylinder at a time to adjust mixture and idle or by using popsicle sticks for idle adjustments. Using vacuum gauges it ran fine as long as the balance tube was blocked off, with balance tube in operation it ran like a donkey having a coughing fit. I had a similar experiences with cam timing, with the standard cam timing it was easy to start but pretty sluggish, changing the cam timing resulted in a quite exciting ride; unfortunately, it was an absolute pig to start, nearly broke your leg if the pistons weren't at the correct point in their stroke. Incidentally, changing cam timing isn't recommended unless you have lots and lots of time, access to appropriately stamped cam gears or written documentation on timing options,. From memory I think you have to turn the engine through something like 360 revolutions to check on valve/piston tangling. Multiply 360 x the number of teeth and you see what I mean by lots and lots of time! If you don't get it right it will result in damaged pistons and bent valves!
 

FOMOGO

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#3
Nice bike. I had a TT120 (650cc) desert racer back in the day. Have a 69 Bonneville now. Mike
 
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