ring breaker barrels

[a.lo]

further to a recent topic on these and the recent interest in torquey chuggers i compared the ports on a barrel i suspected was a tv of some sort to some info on here and lo and behold i think it is the fabled object.
untouched transfers

untouched inlet

no identifycasting[no cutouts in top fin

and to top it , all fins intact.
the problem is this


as if to prove its provenance this barrel has suffered broken exhaust fixings and ring breakage the latter can be sorted , rebore to 68mm (210) but is there any fix for the flange. it has previously had a braze repair the remains of which can be seen to the left of picture any help apperiated , i have a couple of tv 200 gearboxes and i need a barrel to pull them. messd up with the pictures ,ill try again.

[a.lo]

at last you should be seeing some pictures , beer does not help heard it is difficult to weld cast iron. would another braze repair be possible to hold insert/helicoil?

[coaster]

If that is a genuine 'ring breaker' i.e. early TV200 then you will need to have it bored to 72mm (225cc) to overcome the ring breaking tendancy, not sure if 210 would be enough

[shocky]

i would braze that up (make sure its very clean first) then id timesert it or helicoil

[soullad]

Also depends on the sort of exhaust you intend to fit. Those with the short stubby manifolds common with expansion systems will exert less stress on the repair than the clubman sort which have a longer heavier manifold.

[Captain Chaos]

70mm for 225 with a 58mm stroke crank......

72mm may leave you with a pile of fins on the floor....

[coaster]

70mm for 225 with a 58mm stroke crank......

72mm may leave you with a pile of fins on the floor....

Thanks for the correction Jon

[a.lo]

its just i never had much luck with my old cast 225 in the 80's, constant seizeing, so was trying to just bore enough to eliminate the gouges and use a better piston(mb) could those rings cope?

[a.lo]

p.s can i bra?ze with a standard gas blow torch

[shocky]

not on a cylinder it would take ages to get hot enough it needs localised hot heat brazing my distort the cylinder slightly as well infact and excessive heat may cause problems with the bore
the whole cylinder will need to be preheated slowly to say 200 deg then the repair maid and the cylinder cooled very slowly normal under a thermal blanket