F: Frame Comet rear cylinder

[Robert Watson]

Never more than dabbled with Comets so have a question or two.

The rear cylinder F106 attaches to the rear RFM mount with a single stud F118 two washers and 3 F27 nuts. Are the two nuts supposed to be locked together and then left a touch loose to allow movement for heat expansion, like a twin and if so I assume that the single nut side is either locktited or perhaps originally staked so as not to allow it to come loose and fall off.

second question, as this is about to depart for a rally and needs some attention can someone tell me the correct length of the stud, It look to me like this one has been rather butchered so i don't trust it, would 4 3/8" be correct??

Appreciate any comments, well perhaps not any but one with some relevance to this!

Robert

 

[Simon Dinsdale]

I don't know the length of the stud but both nuts are done up tight one at a time as no expansion movement required. The nut on the single side is s mechanically locked by staking and I have seen one where the nut was brazed onto the stud.

Simon

 

[Robert Watson]

Thanks, sort of what I was leaning toward, I wonder why it wasn't listed as F118AS c/w the nut.....

 

[vibrac]

I think there may have been at least two designs for this attachment one as shown on the Vincent spares exploded drawings and one with a captive nut. To complicate matters further on two of my Comets the 'bolt' had a curved low head like a roofing bolt (but no slot) and a raised bar of perhaps 1/16" height on the underside that engaged with the slot in the UFM. You just needed to press the bolt in and do up the nut
Such an elegant solution found twice I cant believe was not a factory item perhaps its light weight suggest's a racing part?
F27 the securing nut is also the same as the rear stand nuts