ST2 transplant process

[Slowmo]

ST2 motor modified and fitted.

Stock width 85mm from CL.

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904 case width 65mm to CL

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With that amount of material to remove the cutoff blade was used to remove the bulk, and a flapper disc to sand back flat. The flycutter then squared it up.

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The flycutter being manually fed is not ideal, but got a useful result. Had to do similar on the other side to get the total width to 139mm. Luckily the swingarm hides the horror.

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[Slowmo]

Had to notch the lower mount to clear the rear shock linkage mounting. Removed 5mm off the left hand lower mount with the flapper sanding disc.

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Fits like a glove, no shims needed. Absolutely chuffed, now to wire everything up to the Speeduino, fit new belts and clutch and get some miles on her!

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[Slowmo]

Getting closer to fire up. Clutch from 906 fitted to the 944. 3D printed clutch holding tool worked well.

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Bit of a setback, ST2 coolant pump outlet is incompatible with Paso pipework, could not work out an elegant layout so decided to bypass the thermostat. Cut up a Ford Falcon header tank hose to make the bypass. Turned an aluminium plug up to block off the upper hose tee (sitting on the outlet pipe in photo). Had to transfer the coolant fittings from the 906 heads to the 944 heads.

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[Mc tool]

Nothing is more infuriating than carefully laying everything out in the morning, putting all the appropriate parts in little labelled plastic bags only to unbeknowingly drop one of the little orings - unfortunately the smallest one that was totally silent as it bounced out the garage door and out onto the sunlit driveway. Lost almost 3/4 of an hour and all of my patience retracing steps and looking under/in things for that tiny o-ring that I knew I had "put" in the bag.

new orings finally.jpg

At least it's all back together now and the casing mods can start without the risk of swarf getting in the cases.....

F n tell me about it . I have been working on an outboard motor and dropped one of the rubber mounting blocks ( 3x2x1cm ), I saw which way it was headed and turned to see where the rest of the stuff went .........that rubber block bounced under the bench , right to the back wall , turned right and went along the wall behind all the fish tubs full of interesting motorbike parts and just slipped UNDER a tree leaf . 3/4 hour later when I removed the fish tubs ( all the time reasoning that it couldnt make it that far ) I still didnt see it . I found it when I decided to clean up some of the crap with a vacuum cleaner.
And I never dropped a valve 1/2 circle collet down the oil return hole in the rear cylinder ...........nah , not me ,