Scooterotica

I heated my crank inner sleave/collar to remove with original type tool (bloody thing didn't work so ended up grinding it off using a dremel very carefully followed by hand files), the crank taper has darkened gone blue, did i use too much heat, weaken the crank.

May seam a daft question but a lot of heat was used as suggested to remove the collar but as above didn't work anyway, i know that you shouldn't use any excessive heat on bearings as if they turn blue it destroys them hence the question.

will be OK as long as you have not blued a bearing surface...

Looked ok underneath the collar/inner sleave once i ground it off, oil seal areas were fairly blue.

I was dubious about putting it back like that so carefully with a dremel again i put a small wire brush attachment on & have gone over the whole taper shaft carfully to remove any 'bluing'.

Concern was as initial post any weakening og the crank.

I've added a couple of photos (if i've upladed right).

Removing the blue doesn't change the fact that the surface got to a change state temperature.

The blue is only an oxide layer, which is commonly used to determine the temperature of a ferrous part for hardening/tempering/annealing purposes.
You can find little comparison tables telling you how hot it got.

As the underside of the inner race looked 'ok' & not like either side of the inner race, i.e blue & the fact that the flywheel bearing sits on this race am i assuming the crank will be ok?.

The drive side is fine as no heat applied to this side, obviously the flywheel sits on the crank but it is not a bearing track - going by what ForemanBob says.

The 'Spanners Manual' states about getting the track hot using a oxyacetylene torch to get it red hot hence i didn't expect any heat issues.

Been riding scooters since 80's but first time i'd taken the inner race off after getting an original type extractor & truing jig, didn't expect it to be straight forward but chuffing hell....

it should be fine if the new track is a snug fit and the crank runs true