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TR4/4A TR4 Gearbox Syncro Clearance

KVH

Obi Wan
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The Buckeye Triumph "Gearbox" article states:

"The new synchronizer cups are probably also overkill. One should measure the distance between the cup and the associated gear with feeler gauges (next photo) and if greater that .030 inches, the cup need not be replaced."

OK, taken literally, this would mean that "too narrow a gap" is bad, but that a larger space is just fine.

This is consistent with VTR which states that the clearance should be between .035 and .040, and should be replaced if the clearance "is less than .030." Meaning, greater is OK, I presume.

I'm asking because the gap on all four of my syncros is about .048.

Also, of lesser import, I guess I should ask, "What is a cup"? The pics of the feeler gauge make it clear what to measure, but I hadn't heard that word being used before.

thx
 
As the synchro rings wear, they get closer to having the face of the ring touch the gear. So yes, more gap is better (indicates the rings are less worn). ISTR when I put in NOS rings, the gap was around .050", so your .048" sounds fine.
 
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