A65 teardown

Moving on to the cylinder head now, valve guide bores mic'd up at .504 but were not concentric so I cleaned and opened them up to .506. I'll be ordering C630 guides from KPMI this week, along with valves and springs.

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Kitchen table valve guide install.

Another one to file under: "Sh*t I couldn't do if I was still married"




got to honing the guides today, shot for .001 IN - .0015 EX, guide hone comes in very handy

 
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Tank and seat combo. Overall happy with the tank (Royal Choppers.. thanks for the recommendation Kommando!), will pressure test of course

Fit, as expected, is a tad "off", I will have to fabricate a new mounting system, planning on using cylindrical isolation mounts for the new front bracket I'll have to design. Seat will require additional glass work, as looks like it was shaped with a roughing rasp

A65 teardown
A65 teardown
 
Snagged Britcycle's last Hayward A65 belt kit, performed the sealed bearing conversion which has been running great on my T140

A65 teardown
A65 teardown
 
Spent the whole summer building a new workshop, so it's been some time since I've had time to look at the BSA project, but finally got around to finishing up the head. New seats have been installed, and with them the KMPI lightweight spring kit fitted at the correct spring height and pressure. New 32mm premiers, I chamfered the heat spacer to provide a nice transition down to the intake ports. Next on to modifying the case for breathing,, will be plugging the rear crank vent near the sprocket and coming up with another solution.

Doug's funeral is tomorrow, so I'm happy I got this all done in time

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New workshop

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Slow going, still waiting on the timing side cases from Ed-V who's doing the bearing conversion, in the meantime been sorting through what I can, ordered a repair shaft for the bodged gearchange, ended up with a slight press fit, used some green LT, but I now have to decide whether to pin or weld it in place, leaning towards pinning as my "welding" skills are not the neatest

A65 teardown
A65 teardown
 

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Early christmas for the A65 project, end feed/bearing conversion is back from Michigan, you can see the re routed oil feed to the crank through the PRV cavity, the welded boss that holds the new crank seal and clip, the dowel feed / o-ring from the inner to outer cover, and you can also make out the needle roller combo bearing under the worm gear. Also new carillo rods and 10.5:1 forged pistons. Also decided to mount the dunstall fairing I've had lying around for years, IMHO the fairing spitfire tank combo is fantastic, sending that off for paint this week.

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More progress, new cam bushes installed and line bored, made up a go-no go plug @.001 clearance, smooth turning with cases bolted together

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Crank ready to install, new flywheel bolts, measured endfloat in the cases at .038, the bearing conversion locks the crank to the TS, but I dropped a .035 shim behind the DS bearing on Ed's advice

edit: crank's been balanced to 70% with the steel carillo's and hi comp pistons supplied by ed, will be interesting to see where the vibes smooth out in the power band

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Fairing paintwork came back, really beautiful work by John Connery

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Being held up on assembling cases by delays in getting new big end shells and a closed needle for the inner gearbox. Figured I'd start to puzzle together the rest of the tranny, already installed new bearings and bushes throughout, but reading up on shimming the layshaft yields a lot of opinions. The TS layshaft thrust washer is standard .115 with the PS @ .120. I can't properly determine the float until the needle bearing arrives, but looking at the assembled cluster I see that layshaft and mainshaft first, with standard thrust washer in place, are not centred very well. I machined a new thrust washer @.140 and that brings the first gears nicely inline and centred. Experts please chime in here. I'll be shooting for .003-.005 float on the layshaft once I get the new needle bearing

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More progress. Test fitting the Hayward belt sprocket with a dummy shaft, good clearance behind the pulley but the two front stator stud mounts needed to be machined down a bit for belt clearance

A65 teardown


Shells arrived, rods installed

A65 teardown


Before assembling the cases I test fit the camshaft pinion, counterbored back of sprocket by .005 to allow the cam to be pulled up tight to the TS bush (spring and cup breather was eliminated on primary side)

A65 teardown


Bottom end assembled and installed in frame

A65 teardown
 
I’m interested in folks thoughts on this… if good quality modern oil is used (see Comnoz’ guide) and if a modern remote oil filter is used… does the timing side bush need replacing for a bearing?
About 12 years ago while working at Raber’s I rebuilt a 1959 Super Rocket. The bike got converted to a desert sled sometime in the sixties along with high compression MC pistons. The owner had a reputation for being an aggressive rider. When I tore down the motor the engine showed signs of neglect, however the crank was perfect. The main bush was somewhat corroded by the dirty oil but measured within factory wear limits. We ended up replacing the main bush and grinding the main journal but not the rod journals.
 
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