Kevin, I'd never considered those tiny springs to be failure prone (except for getting lost when a hub unexpectedly comes apart!)   It seems that about all that could happen if they are "weak" is that you would get less of a detent or 'click' between gears.  All the linkage types used on the Mini have other mechanisms to act as detents built into the shift rods, so I don't see how they could be causing the down-shift crunch.    Can you explain your experience where it was the fix?

Sounds like weak synchro hub springs to me. I just fixed one with the same symptoms on 3rd gear.

[edit] these are the springs... if you pull it down again I'd do the 1-2 hub as well.

//www.minimania.com/part/22G2262/Transmission-Spring-4-Synchro-Hub-_-Mini--Mini-Cooper-S

thanks for all the suggestions: Oil- Car has about 150 miles on it now, and I changed the oil already. Shifting up to third works good, it is only downshifting and then when you go to fast, or too slow. Double clutch helps. So I will put some more miles on it and be patient.

Jerry

May not apply here, but...
Not all baulk rings are the same quality, I had some non-Rover ones once that were such a poor fit (oval and wrong taper)- 2nd gear took 5000km to bed in. Even then it wasn't great.

Agree with Jamal because of my personal experience.  after full rebuild several years ago going into gears was just not quite right overall. After about 500 miles wanted to get the original oil out and then thought I'd go after clutch adjustments.  Changed oil with Valvoline VR1 20/50 Racing (no let's not get into the oil debate please), and added 1/2 bottle of STP Oil Treatment (7oz or so) which has ZDDP and I guess some other vodoo stuff.  Made a huge difference.  So, time and get the old oil out?  Never thought about it until this post because it does not make sense.  I just know that it made a big difference.

For what it's worth.  J

looks like good advice jemal, can you check out my thread about my clutch issue and maybe weigh in on that as well? thanks

Give it a few hundred miles of GENTLE shifting.... and no synthetic oil... until it has a chance to wear the synchro to the exact shape of the gear cone....   A high idle speed can make it quite sketchy to down-shift in particular, and especially with new synchros!.... it needs full engagement to the gear cone to get it spinning much faster on the shaft to smoothly engage the gear!

..... Don't take it apart yet!!

It would probably be a good idea to check the clutch hydraulics and linkage before pulling the engine. Marginal clutch disengagement can cause some odd symptoms and they can be different for different driving styles. A 3rd gear crunch for some people might never happen for others.

It's certainly an easier place to look for the problem.

Kelley

It's take it apart time - the crunching is only going to get worse...

With the block off the 'box, you can just about measure the synchro ring gap.  With new synchros fitted (assuming they are genuine Rover and not the el-cheapo cheese ones) if the gap is less than 30-35 thou then the gear is knackered.

What oil are you using? It's not really an adjustment you can make after the fact. Condition of what I call the ramps ( the cone shaped side of the gear ) and the tiny dog teeth have a lot to do with it. I plan to assemble one today I'll try to make a list of things to check. Of course it should all be done upon tear down. Did you replace the shift forks? Steve (CTR) 

I don't remember the gaps between the syncros and gears. I bought the syncros from GuessWorks. I can't even remember if new springs came in the kit.

I just checked the kit. It did come with new springs. Jerry

It can also be weakened springs in the synchro hub. Some aftermarket springs sold now are weak Chinese rubbish. If the springs are weak, there is not enough rotational drag created on the baulk ring to let it get `baulked' by the outer sleeve during the shift, = crunch...

Here in Oz I can buy stronger springs than stock.

When you rebuilt it, what size were the gaps between the synchro rings and the edge of the gear ?
Sometimes just putting new synchros in isn't good enough if the gear is worn.

rebuilt transmission with all new syncros, upshifting is good, but downshift to 3rd and you get a crunch about half the time. This is a Verto Clutch , late rod change transmission. Only 150 miles on the transmission since the rebuild, so do the syncros wear in, or is there some other adjustment?

Jerry