H55f
The H55 can be noisy at the shifter. The newer ones have an insulator built into the stick. You can tell the difference because the stick is quite fat half way down.
Recently fixed the sons H55. It was real noisy in all gears except 4th.
The problem was the rear counter shaft bearing. The bearing is a straight roller which uses the shaft as the inner race. The shaft gets worn and the hard surface wears off and all the gears get out of line except 4th which is direct. The fix is replace the bearings in the trans and the counter shaft.
There is an after market gear available for about $400+
However there is another way.
One of the weakness of the H55 is the non replaceable inner race of the rear countershaft bearing. All the other roller bearings which matter have replaceable races except that one.There are other needle roller bearing which use the shaft as the race but they don't carry much load, they only turn when the transmission is not in that particular gear, so the gear just floats on the shaft.
So make the race replaceable and reuse the counter shaft.
Turn the rear bearing race in a lathe, the material is relatively soft, carbide tooling has no trouble reducing the diameter. Find an inner race from a needle roller bearing that has the same outside diameter as the original shaft race. Then shrink fit the new race to the shaft and you have a new bearing surface for the new roller bearing to run on.
The sleeve is slightly shorter than the original race but the bearing surface is plenty wide enough for the width of the roller in the bearing. Used 0.0025 + shrink fit and heat the sleeve up a bit ( heating base on a coffee maker works well to heat the sleeve) and drop it and tap it home. You may have to polish the sleeve a little to get it to 40mm diameter.
This reduces the cost of the overhaul to cost of machining and the new sleeve ($30.00 for the sleeve?) Overhaul kit from Kurt $200? Plus the time to do it.
Hope this helps.
Thanks jb