Join Date: Apr 2002
Location: Dandridge (Near Knoxville), TN, USA
It is very much like a car engine in that it is liquid cooled, inline, 4 cylinder, overhead valve, etc.. I have had my engine apart, and it is built almost exactly like many car engines, just smaller than most. The cams, followers, valves, and valve guides are of automotive design.
It does have one area that is different from MOST (but not all) automotive engines, that is the NikaSil plated aluminum cylinders, where most car engines that are aluminum block construction have cast iron cylinder liners.
The main and connecting rod bearings are certainly automotive type. So is the chain drive system for the cams much like many automotive engines. The pistons are aluminum, as are almost all automotive engines.
I have read on various oil manufacturer's web sites that their oils are formulated for "high temperatures of air cooled cylinders", with "friction modifiers for engine oil lubricated clutches", but none of this exists on the LT.
If you took the cutaway picture in the service manual for the LT, and turn the picture 90 degrees, show it to anyone that is familiar with engine design, they would have no idea it was a motorcycle engine, and would think it is from a car.
So, yes, it is very much like a car engine in almost every way.
The sprag clutch certainly is not automotive, but just a way to allow the starter motor to be small and short, with no typical automotive solenoid driven sliding gear engagement to the flywheel (commonly called a "Bendix" drive). That takes a lot of space lengthwise. Also on the LT it easily lends itself to allowing the starter motor to perform a dual function, engine starting and reverse drive.
Can you think of any ways the LT engine is unlike a modern small automotive engine?
I don't want to achieve immortality through my work...I want to achieve it through not dying.
EX: '01 Black LT, BAT BYKE (Totaled at 110,000 miles)
IBA SS, BB, BBG, 10/10ths.
No bike now, but maybe in the future.