Quote from: mb124 on September 06, 2012, 02:46:55 pm

Hi Mark ,
it`s shown in the first picture in the post "Reply #242 , Feb. 19.2011 " , page 17 .
You can see the "2" cast into the right of the locating fin on the oil filter cover .
This is exactly as shown in the Service Bulletin #13 , 1/26/70 . Also , I have 2 of these covers (finned , internally ribbed, "2" cast )
Many thanks for sharing the #97 story ,  outstanding presentation .
Best Regards
Geir

Thanks, I was confused and thought the #2 was on the smooth oil filter cover.  So the #2 finned cover is the latest (last) version of the finned cover?

Hi Mark ,
as I interpret it : the internally unreinforced covers were prone to cracking around the oilfilter bolt hole ( yes , the cover on my VIN5120/E5306 has cracks ) .
To remedy this , Honda made an internally ribbed cover with cast mark "2" , to replace covers from VIN1783 ? -9554 . It`s reasonable to assume that bikes after VIN9554 was fitted with these upgraded covers .
Later bikes has higher numbers cast in , I have "7" , "3-1" , "3-2" , probably from K2`s and up .
The #13 Bulletin states " All original center bolts should be replaced with the modified center bolt at the earliest opportunity " . For the covers : " All oil filter cases should be checked for hairline cracks around the center bolt boss when installing the new center bolt . If any cracks exist , replace the oil filter case with a modified case " .
So with no apparent cracks , the covers survived the upgrade , the 14mm bolt didn`t .
Luckily ,some bikes also escaped the upgrade completely....
Cheers
Geir

Hi Steven ,
I had a closer look at my finned , unreinforced covers .
1st cover  off VIN5120/E5306 : 14mm bolt ,painted silver by myself .
2nd cover , off Ebay : 14mm bolt , silver paint
3rd cover , off Ebay : 12mm bolt , silver paint
None of these covers has a casting number on either side of the 12  o`clock locating rib .( easy identifying point without removing cover from engine )
I also have 2 off covers with "2" cast in , as shown as the replcement cover from Honda in Service Bulletin #13 . Bolt changed from 14mm to 12mm together with "#2" cover.
 This "#2" cover is also shown on p.17 in the #97 restoration. 
Strange : the mating locating ribs to fix the oilfilter cover are present on my VIN1161/E1306 engine case ( not on #97 ,see p.17 ) . So it means engine #1306 was already prepared for the ribbed cover .(I have a Yamiya cover fitted )
I think you are right in assuming that all later sandcast`s was fitted with the ribbed , unreinforced cover (no cast number ) , silver painted , and 14mm bolt .
Amazing how much archeology that can be applied to an oil filter cover...

All the best

Geir

Mark ,

great  if you can get a batch of "short knurled nuts " cables made .
I need a set for my VIN1161 .
Congratulation with VIN97 post , fantastic story , very useful information .

Geir