Maybe try a different gearbox oil Harryman?
If you read the Wiki link
again carefully...
Wiki on T25 gearbox reluctance
you'd see that is exactly what one of the workarounds suggests and that it is not Syncro specific, or even T25 specific!
and Redline would not research, develop, market and advertise an oil specifically for this sort of problem if there wasn't a general problem with many boxes, across a wide vintage.
Would they
?
I've been driving vehicles for 40 years, and was stripping down gearboxes over 35 years ago - I don't do it now but take a peek now and again - they haven't changed much as far as I can see. Synchro baulk rings are much the same, as are the teeth on the dog clutches they synchronise.
It's a well known engineering compromise between gear size and their consequent rotational inertias versus the frictional torque generated on the hub faces required to synchronise their speeds quickly - and whilst one might think a more viscous oil would help, its film thickness prevents this - yet another compromise. Design engineering is usually all about carefully controlled and calculated compromises.
N.B. The early 850 minis (1959, straight levers) did this from new, or within a month or two, and had to be re-designed pretty sharpish.
All I was saying is that a box being slow when cold means if forced it will refuse or crunch the change, and is
NOT something that condemns it outright... and in fact is quite common, witness why the Wiki article was written in the first place - to help members complaining about this.
I didn't drag this back up, I just made one straightforward comment based on FACT - why people can't accept it I just don't know - its engineering common-sense backed up by a lot of people saying it happens (even on nearly new boxes - allegedly)
