MBS206 said:
It's because the layway (I think that's its name) shaft is normally spinning in the wrong direction to engage properly into reverse synchros, hence, they don't build a box with reverse synchros.
And if you're slightly rolling, the layway shaft and input shaft are spinning in opposite directions, hence they crunch until the input shaft stops, and engages.
Yes and no,
the clutch and laygears will always spin in the direction that they are goin except if u succesfully select reverse while rolling foward, then it will spin everything in reverse. its the same with selecting 1st while rolling back. In between the reverse gear and reverse lay gear is a reverse idler gear which reverses the direction of the reverse gear therefore giving u reverse torque. in your box, when the clutch is engaged, all ur gears and laygears are spinning however, only ur selected gear will spin ur output shaft and when u disengage the clutch all gears slow down to a sort of factory set idle (it would be in ur manual wat speed the clutch and gears idle at) when it is in idle the gears slow down so u can select them however in reverse, if the outputshaft has been spinning one way, so has the reverse gear selector which would be opposite to the reverse gear, and thats why it can be hard to select reverse sometimes, becos ur selector is spinning the opposite way to the gear and the clutch and laygears havent slowed down to idle yet
in the T5 boxes, it can be difficult to select reverse at times but in the Getrag boxes they improved on this problem, even though at times it can be still pretty hard. i found i can select reverse even if im rolling foward a bit as long as the gear matches up, if it doesnt, i can feel the shifter not want to go in. the best way to get it to match up is let go of the clutch in neutral and let spin a bit and then try again. it should go straight in
note: ur clutch and gears will not spin at a constant idle they will slow down to a stop if no torque is applied to them after a certain time
P.S sorry for such a long reply, i just get carried away when comes to cars, its the problem of being a mechanical engineneer