Hitchcocks Forum

can anybody tell me the difference between the avl engine in the thunderbird and a normal say bullet engine

More to the Point Mate Whats Your Bike Year and Model ??..I Run A AVL 2005ish Machismo the Frame and Running Bits are the Same as My 350 99 std How ever the Engine is Described as a 350 Home Mkt AVL as Fitted to The 350 Thunderbird..Lastly Our Host Mr H.Provided me with a Thunderbird Manual For My Engine Info.
Now if its a 500 Officially imported Then "Wow" thats a Can of Worms..But in MHO if its a 350 Home Mkt AVL 2000 to 2010 A Thunderbird is a Good ENGINE Guide...Cheers Craig (Nottingham if you are Local)

Sorry direct info: tell me the difference ......Higher Rocker coverer's as per electra...Most not all Cut off Section off Timing gear where Points would be as Most (Not All) have electronic Ignition..hence most Not all have the ugly primary cover,,Some (Mine) had the 5 speed gear box L/h as std..and of course if the bikes a Thunderbird you have twin clocks,fuel gauger,&peanut tank high bars...Enjoy` So Electra But Not Electra Prob 350? Very Liked in india..500> prob electra?;0) imho

Brief summary:



Classic Bullet Engine: alloy con-rod with steel big-end eye pressed in, RE "floating bush" big end bearing, crank pin fitted with retaining nuts. Oscillating plunger oil pumps. Smoother timing cover. Ignition by contact breaker assembly or by magneto behind the cylinder. Thicker stem cam followers. Cast iron cylinder barrel (alloy for competition of after-market modification). Older-style cylinder head with hemi-spherical combustion chamber, 2nd 14mm thread for decompressor valve. Rocker spindles held in blocks boltd to the cylinder head.



AVL Engine: Japanese style short steel con-rod with needle roller big end on plain crank pin running directly in the con-rod. Crank pin is press-fit in flywheels, no retaining nuts. Gear type oil pumps with lumpy timing cover. Crankshaft-mounted ignition trigger, no contact beaker assembly or magneto fitted. Thin stem cam followers with revised cam profile. Alloy cylinder barrel, shorter than the cast iron version. Redesigned head with pent roof combustion chamber, rocker spindles mount directly in the head casting. No decompressor valve in the head, valve lifter fitted in tappet chamber.



A.