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The stock TW Crank is 55.7mm and the new TW Crank is stroked to 62mm with the bottom of the rod ground and polished. With the 71mm piston and 62mm crank it will be a TW 245!
 

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FUUUUUUN! Lot of work, can hardly wait! I recomend "Flight Of the Valkries" for garage assembly background music!





(Yes I very well may have spelled "Valkries" wrong! kill the wabbit Elmer!)
 

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Sudden feelings of inadequacy.



I need a hug.
 

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Lovely. A BiPolar Bear.



Puts me in mind of a Far Side cartoon which is captioned "Bummer of a birthmark, Hal".
 

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The stock TW Crank is 55.7mm and the new TW Crank is stroked to 62mm with the bottom of the rod ground and polished. With the 71mm piston and 62mm crank it will be a TW 245!


Interesting difference in the beef of the TTR rod small end.
 

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Looks like you filled the side of the existing pin hole with weld? Then machined a new pin hole? Why weld the pin to the crank halves? Was new hole not a press fit? If not, are you concerned about concentricity of the two crank halves or were they jigged? And did you have concern of the lower rod bearing welded in there and not being (easily) serviceable, or weighed the odds of that bearing going bad as slim and say the hell with it?



Did you think about an eccentric pin in the original 55.7mm-stroke hole if you were going to weld the pin to the crank area anyways? I'm not sure if those are frowned upon, just curious and wanting to learn
 

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Another ?, With the large end rod ground in that manner, What is the clearance at BDC to the windage casting on the cases?, and ...What is the clearance from 90 degrees(closest point in revolution) to the gears on a six speed transmission? (those seem like the two tightest interference points)
 

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Looks like you filled the side of the existing pin hole with weld? Then machined a new pin hole? Why weld the pin to the crank halves? Was new hole not a press fit? If not, are you concerned about concentricity of the two crank halves or were they jigged? And did you have concern of the lower rod bearing welded in there and not being (easily) serviceable, or weighed the odds of that bearing going bad as slim and say the hell with it?



Did you think about an eccentric pin in the original 55.7mm-stroke hole if you were going to weld the pin to the crank area anyways? I'm not sure if those are frowned upon, just curious and wanting to learn


Eccentric pins are doodoo, as far as I'm concerned. Usually (but not always) the budget alternative path to a stroker. If the press fit gives out they tend to act like little crankshafts-within-crankshafts, hammering in all kinds of random orbits. If I went that route I'd want them fully welded. Round pins won't do that.



This is the "right" way to do it. Normally the tack welds are only on one side, or shallow enough to be ground right off for future crank disassembly. I will agree with you that those are a bit more permanent looking than most, and on both sides.



Appears permanent, but I'd still sleep with it.
 
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