1967/1969 Bonnie Rebuild Desert Sled Project - Any Advice

The internal cable/protrusion length is the critical length , too much and you can't apply the brakes , you need to make a spacer to take up the slack or a new cable with the correct protrusion length

 

Here is a cable end that replaces the original and lets you shorten it at the drum end, cable goes in at top and loops around and back out the top, then bolt lower part to brake arm and adjust inner cable and tighten top nut n bolt to squish cable. https://steadfastcycles.com/product...s-adapter-triumph-bsa-norton-barnett-usa-made

 

i set it up for break-in on assembly. generous assembly lube on rod ends, crank, cams, and tappets. no synthetic oil. i use brad penn 30w break in oil.

from here i depart from conventional wisdom. i assemble the jugs dry-- no oil on cylinder walls, zero.

one drop on front and rear piston skirts, zero oil on the rings. some people use more oil on cylinders, like a wipe with an oily rag, then wiped as clean as youcan with clean paper towels.

whatever you do, when you start it, keep the rpms up above 2000 for a couple of minutes while you verify oil return.

what i do then is take it out and ride it. up and down through the gears. no lugging, no racing around at high rpm, but load the motor to force the rings out--firm acceleration, firm deceleration, open throttle, closed tbrottle. . . . no extensive idling. keep the rpms up so the oil is splashing around.

do this for half an hour or more. i have an airstrip where i break in motors, and that works well.

after that, take it home, adjust the timing and idle, torque the head, adjust the valves.

ride it firmly but not crazily for a few days and youre done. i routinely do this to a fresh race motor, and after several hours of this, its ready for 8000 rpm WFO, even with pretty close piston tolerances.

other people will have othwr suggestions. there is no one right way. you can get the same results with different techniques.

 

Fascinating thread for a non-techie like me, I must say. Fantastic support from some very knowledgable members here, but kudos to the OP too - it's a big project.

 

yes, use a strobe light for final timing. the dactory just static-timed the motor and sent it out. you can do better. i recommend a dial back to zero light, so you can get actual numbers fir advance and so on

i learn stuff on these forums all the time. during thev80s and 90s there was nowhere to leafn. the internet has changed all that by facilitating communication and access to old information.

just be aware tberes BS out there too

 

nope

use the 650 figures unless youve gone to an aftermarket cam.

even then the clearances are somewhat approximate. you can modify tbem a bit to change your valve timing.

 

nope

use the 650 figures unless youve gone to an aftermarket cam.in that case do what the cam perso n says to do.

even then the clearances are somewhat approximate. you can modify tbem a bit to change your valve timing.