[Darvin Jahnke]

OK guys here come the questions. When was the first year for the UCE engine and the first use of efi? Also what is the AVL engine as compared to earlier engines? Thanks.

[TWinOKC]

2009 was the first year of the UCE and also first year for EFI. 
2009 was also the last year of the AVL.  RE are subject to change any time of the year.

AVL has an aluminum jug, older models were iron.

May not be exactly correct on everything but others will comment if I am off a little.   

[Darvin Jahnke]

Thanks for the reply. When did the AVL replace the iron cyl?

[TWinOKC]

Thanks for the reply. When did the AVL replace the iron cyl?

2006 maybe

[Arizoni]

The AVL was a Swiss re-engineered engine intended to meet some of the worlds emission standards.
In doing this they replaced the old iron barrels floating sleeve bearing on the big end of the rod with a roller bearing.  They also changed the aluminum con rod to steel and replaced the old reciprocating twin piston oil pump with a gear pump and modern paper oil filter element.
The ignition was also updated to a CDI.

The UCE's inherited most of these changes with the oil pump becoming a gerotor style.
Roller type hydraulic valve lifters, automatic compression release,  and fuel injection were added along with a beefier electric starter sprag clutch.

Most of us have found this new UCE engine to be reliable and for the most part, trouble free.  I have over 8500 miles on my G5 and several of our members have over 15,000 without any problems.

The chain and a lack of proper protection from sharp metal edges for the wiring harness seem to be the only areas that could be improved.

[Darvin Jahnke]

That information is very helpful. Thank you.