35 degrees getting hard to find

[pisten-bully]

Last couple of top end jobs I insisted on a 35 degree grind on valve seats and faces, now I'm wondering what effect, if any, a 30 degree grind will have. Much easier to find 30 degrees than it is 35 degrees!

[tfburke3]

You need someone to face off a stone to 35 .Also you wouldnt want to reface the valves to 30.
I like oversize valve heads and tell the shop to cut the seat removing as little cylinder as possible and then size the valve to the slightly oversize seat which will not be lowered as much as the standard grinding the seat to fit the valve.
Tom

[kitabel]

Reducing the angle will lower the seat

[T. Cotten]

I'm a little confused, Harry,..

My common Sioux grinder kit let me diamond-dress a stone to any angle I wanted. (Still got it, but its too tired now...)

When I had to get serious, I bought a 35 degree NEWAY cutter with a top angle as well, since I had the rest of the NEWAY necessities for everything else.

Haven't done a valve job in years and years, but it all still paid for itself!

...Cotten

[pisten-bully]

You need someone to face off a stone to 35

That guy's not around anymore. Reason I'm asking is because one can buy Neway tools to hand grind seats and faces, they offer a 35 degree seat tool (also 30 degree) but their Gizmatic valve refacing jig only does 30 or 45 degrees.

I can probably find another shop willing to do it but I figure I'd wind up paying him more for 35 degrees (maybe for a new stone) and I'd like to try and do it myself!

Thanks for the replies!

[PRG]

Howdy sir,

Did my 346 to Porsche’s air cooled spec of 32 degrees with a hand held Neway at the link below in 2010 and it’s run like the proverbial top since. Throw in some valve stem seals, lean it out a smidge, Clyde Crouch electronic ignition and run extended tip plugs for a much cleaner combustion.

https://petergz.smugmug.com/Motorcyc...-346/i-DcM7XSk

[pisten-bully]

Did my 346 to Porsche's air cooled spec of 32 degrees with a hand held Neway

..wait, does that mean one can adjust the angle on the Neway jig? Advertised as 30 degree and 45 degree but you went to 32 degree so I'm curious!

[PRG]

Howdy Harry,

No, Neways are not adjustable and very glad you caught me on this one, I actually did mine to 45 degrees......like millions of engines running around today. Why? Because that works and a 45 was at arms length in the shop to use at the Tim. And for those in the valve business, cutting Kiwi sourced valves to 45 degrees does not disturb the all important margin, especially so in flatheads which can run high exhaust valve head temps.

[pisten-bully]

Thanks Peter! I had guessed you had machined the Neway cone to 32 degrees

45 degrees...hmmm. It works for you and lots of other motorcycles ...but I'm having difficulty understanding how much material has to come off a new valve pre-ground to 35 degrees, so maybe I go with all new valves at 35 and dress the seats again to 35 as the way to go.

[PRG]

Howdy chaps,

As a somewhat humorous aside, that somber business like Neway tool you see clamped in my vice. Called a gizmatic....a naming I’d speculate would be more associated with adult store merchandise. Again, speculating, no first hand knowledge on the latter.

[T. Cotten]

Howdy chaps,
As a somewhat humorous aside, that somber business like Neway tool you see clamped in my vice. Called a gizmatic....a naming I’d speculate would be more associated with adult store merchandise. Again, speculating, no first hand knowledge on the latter.

I love my NEWAY tools, PRG!,..

But I'll pass on that one. For four hundred bucks I could have a third valve grinder, and probably get a better finish.

Neither of my lathes cost that much, and can be just as proficient at re-surfacing a valve. (Seats, not so much!)

....Cotten