1098 Minor clutch with 1275 Spridget flywheel?

[Oldmogman]

Does anyone know if the standard 1098 Minor clutch pressure and friction plates can be used with the 1275 Spridget flywheel?

[philthehill]

As standard No.
The 1275cc flywheel must be/can be re-faced and index drilled to accept the 1098cc clutch cover fixing bolts.
This is a 1275cc flywheel which has been re-faced and index drilled to accept the larger clutch.

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[Oldmogman]

Thanks Phil

Assuming that's the front of the modified flywheel, it looks like the protruding part of the Sprite flywheel where the friction plate sits has been machined flush - is that correct? And what is index drilling?

Would that affect the operation of the the standard Minor clutch, or could the difference be taken up by adjusting the clutch linkage?

Alternatively, could a 1098 Minor flywheel, drilled with six bolt holes and two dowel holes be used instead?

[philthehill]

The photo is of the face that the clutch pressure plate is attached to.

The raised center of the 1275cc Midget flywheel has been removed to give a larger friction surface.

You have to mix and match the clutch release lever parts i.e. suck it and see.

You could use a 1098cc flywheel but the 1275cc Midget flywheel is also located by a register which is important in maintaining the security of the flywheel on the rear of the crankshaft.

Index drilling means that the clutch pressure plate retaining bolts are in the right place and at the right degrees apart.

Whilst not a standard 1275cc flywheel the register can be seen and which fits over the rear of the crankshaft flywheel flange.
This flywheel was specially made for me in alloy and is ever so light.

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[Oldmogman]

Hi Phil

Thanks for the clarification.

Could a locating boss/spigot sold for fitting a Minor flywheel to a Marina crank be used to fit a Minor flywheel to a Sprite crank?

[philthehill]

Everything is possible with the right tooling and parts.