T140 g.pin / small end clearance

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Jan 1, 2013
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I've finally got round to starting to build my T140 engine, with the TSS crank and specially made rods from Steve Campbell (Thunder Engineering). The virus got me, hence the delay. Anyway, the gudgeon pins seem far too tight in the small ends, especially the timing side one. The drive side pin pushed through fairly well and the piston can be rocked by hand without much effort, But the timing side piston requires considerable effort to rock it. When looking at the g.pin while rocking the piston, it is the piston moving around the pin, not the pin in the rod.

I tried applying heat and it all felt fine (not a great deal of heat - not too hot to get hold of the piston). I have never had gudgeon pins this tight before in a Triumph engine - usually, the pistons will wobble back & forth freely under their own weight, with all the movement being between the pin and the rod. So my question is, how tight is too tight? I will give Steve a ring on Tuesday but if anyone can give any advice / info in the meantime, I'd appreciate it. Thanks.
 
Both of my gudgeon pins were tight in the Thunder Rods on my Dommie rebuild. They had to be reamed.
 
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