The prob with the bigs is quite poss the disparaty in the dynamic load statts.also EVERY one who has seen the oil feed hole in crankshaft is gissmayed how small it is to feed the big end .

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IF IT BLEEDS WE CAN KILL IT ,THIS STUFF WILL MAKE YOU A GODDAM SEXUAL TYRANASURUS ,YOUVE BEEN PUSHING TOO MANY PENCILS DILLON .GET TO THE CHOPPER

Another thing you probably need with a stroker job are funny pistons. The extra sweep ups the compression too much and if you increase the piston clearance you lose the squish band just making an oversized donkey engine!

I've just been reading up on how different length rods (for the same stroke) affect the way an engine behaves - 'tis very interesting

I'm always amazed at how little lubrication a roller bearing requires. My mate rode his Knuckle Head 8 miles home, (carefully ) after the oil pump drive gear sheared, and the big end was unmarked.

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If your dreams don't scare you, they are not big enough.

http://ecmspy.com/download/gunter/image ... rmfoto.png

Screenshot, unfortunately not very clear, showing a larger crankpin, slightly offset. Engine gained a few extra cc displacement that way (IIRC 1280 vs. 1208 cc with a standard crank and bigbore kit). Engineered and manufactured by LuckyHands.

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"It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
Terry Pratchett

Is that the Jakus engine? Were they 08/09/10 rods?

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08 Specialized Langster

Yes, it is. The engine was built in late 2008, so it might be possible that they took the rods from a thunderstorm engine. OTOH, I have a very faint memory, that the original rods were used, but 4 mm larger bore seems a lot more to me.

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"It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
Terry Pratchett

Yeah, reading that stuff can give you rod fever!

Longer rods increase the piston dwell at TDC which is good.....but also make motor more sensitive to gas flow and exhaust scavenging. I suspect this is one reason (not just the stroke length) that the XB9 and 12 combustion feels different.

Not sure if this has any relevence to rod length, but one theory is that two valve engines benefit more from stroking than overboring as opposed to 4 valvers with their higher valve circumference. For this reason, I always felt my TR1/XV1000 needed a longer stroke, because all the aircooled XV motors were limited by the same 750 heads and valve sizes (to satisfy US EMAP evaluation). This was well demonstrated by the higher efficiency of the sleeved down 699cc > 700 cc tariff buster in the 1980's and later XV1100 (1063cc) motor, which ran sweeter than the old 981cc......for those who have ridden them both.

Thanks for that DrB its nice to know there could be life after tick tick boom...

....and maybe a bit meaningless if you've not seen inside the head of an XV!

Still, this months American V continues with it's series on enlargement of Harley motors with some nice pics of funny topped pistons!

alf's motorcycles in worthing use them for some of their cranks. when i phoned they couldnt give me a price so didn't use them

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BUELL-Turning riders into mechanics since 1983!!!