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Valve cutting/grinding on T140

7K views 4 replies 2 participants last post by  Mr.Pete 
#1 ·
I've searched a bit in this forum but have been unable to find specifics about the valve seat angles as delivered from the factory. One of my valve seats on my head is sufficiently corroded to require a new cut.

Were the '77 T140V bikes delivered with a single angle valve seat? Was this 45 degrees?
Is it now prudent to use a 30/45/60 degree cut?

I'ld like to do as much of the work myself as possible and am also wondering what is the least expensive tool I can buy/borrow to do the job.
 
#2 ·
You'd get most of the job done with a double-sided 45/30 Neway cuttter,1-1/2" body.You'd need radiused blades on the 30 degree side,so you don't cut into the hemi when you do a top cut.
About $150 + maybe $30 for a pilot shaft.
You might not need a 60 or 70 degree included angle single-sided cutter for the throat.About 1/2 price of a double-sided cutter.http://lib.store.yahoo.net/lib/yhst-58082516732612/newaycuttermanual.pdf

You might find something cheaper,but not better value.
 
#3 ·
Ok, so the Neway cutter is THE tool to use. That was a very helpful link about using these cutters. I'll have to read it again more carefully to decide exactly what to buy. From what you say, Pete, it sounds like I can get away with just the 30/45 degree cutter and save the money that the second 60 deg. cutter would cost. Correct?
Two immediate questions: Can the same 1-1/2" body cutter and blades be used for both intake and exhaust valve seats? Is the expanding guide a better purchase than the fixed-tapered guide considering useability with a wider range of valve-guide ID's?
 
#4 ·
From what I've been able to find, the 5 blade cutter is much better to use than the less expensive 3 blade cutter. The 3 blade cuts very aggressively and more prone to leaving chatter or other irregularities. So, the kit with 5 blade cutter head, expanding pilot, T-wrench, and set of radiused blades comes out to over $300 new. Ouch. Maybe I can find something used on ebay or Craig's list.
 
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