Engine Case Stamping Charactors

[DW69K0]

Starting new discussion-

The earlier sandcast engines only have a two digit date (month & date) and E1 on the back of the top case but do not have the "T" as shown in this photo (see attached)
When did the T charactor start to appear? Was this added in later production moths? Where theses cases cast at a different factory or different time period? Was the "T" used for replacement cases sent to dealers or did it appear in normal production?
I know the two engines that I own do not have this additional charactor on the cases and mine were both Sandcast in June.
Can someone with an engine cast after June weigh in on the "T" casting charactor.....do other production sandcast engines have T  charactor on their cases?
Thanks for any help,
Duane

[DW69K0]

Attached is a photo of E1971 that shows difference in cast characteristics for comparison purposes.
DW

[Steve Swan]

Hi Duane,  when i get a chance i'll have to look at my cases stamped 2241 and 4350; it's kind of hard to see those casting marks when the engine is in a completed chassis.  i know 254 has no casting dates, but i can't remember if it has E1 on it.  there should be members out there with bare cases or engines out of the frames to report in.

[Nielsen]

It is very easy to see with the engine in the frame. My E1002276 is stamped: E-1
                                                                                                                6 2 without T.

/nielsen

[DW69K0]

Steve,

As nielsen replied, yes it is very easy to see the cast characteristics on a complete bike, but you might need a light source to see them. My newest engine is 3599 cast on 6-24 with the E-1 but no T.
Curious to see what 4530 shows since this was probably cast on 7-10.

I run a foundry, so trying to understand what purpose the T had, since it have to be reverse pressed into the sand prior to the final pour.

DW

[Steve Swan]

4363's Evin is 4540, casting marks include "E1," with a date of 7/21 on upper case and no "T".  as far as i know, frame 4363 came from factory with E4540.  i can't remember what the lower case date mark is.

E2241 marked with "E1," dated of 6/2 on upper case and no "T".  the lower case is marked 5/30.    E2241 is not original to frame 2157.

a number of frame/engine vins listed in VIN Directory have the casting markings listed.

[kp]

I checked the VIN directory and would appear that these french sandcast cases  dated as 9/11 (or 11 Sept for those of us who know how to write dates) are at the latter end of sandcast case production. My earlier view (not a fact) is that the factory had a number of unused cases when changeover of diecast occurred. They could have been the cases kept for parts inventory. Rather than trash them they were used in normal production. There is no major impediment to swap the internals over from a diecast to a sandcast so it would make good sense to use these cases. As for the T; it's a mystery

[Marcello Tha]

Evin 7083 , casting marks include "E1," with a date 8-28 on upper case and no "T". 

Marcello

[DW69K0]

What interesting to me is that the Japanese language does not have the letter T used in it, so it must have some significance being on the casting.

I wonder if the T started to show up after some design changed in the internal or external cases as an indicator of design change.

Interesting to see more cases from late in production to see if this occurred on every case that was cast after a certain date.

Keep sending higher E numbers with casting characters.

DW

[kenhan]

Either of my E1004957 (7-26) or E1007384 (9-2) has any T, and one of them are really late in production.
Sorry for bad quality on pics!

/Ken

[DW69K0]

I have a theory that the T designation was used on the last run of Sandcast cases. The factory was producing about 60 cases per day from April through the first week of September. this equals 7,200 cases plus the first early 260 or so without date characters.

E7384 was cast on 2 Sep (for KP) only 30 cases away from the end of the Sandcast production run, so as the factory switched over they must have cast another approximate 100-500 Sandcast cases for replacements or dealer extras maybe using the T as an identifier. Of course, this is only some rough math based on the information we have available.

The factory would have made extra cases each month they were casting for earlier replacements that would need to have been available for the dealers as they received extras throughout the year.

If they continued to cast cases through 9-11 it makes this theory possible to have kept up pour rates while they introduced new die cast tooling. A factory normally will run both processes until all the bugs get worked through a newly introduced production method.

Thoughts?
DW

[CBman]

DW69: thanks for interesting topic. We just need to find any old japanese employe, that was casting these cases..........

[DW69K0]

Old employee? They would only have to be 60 
DW

[DW69K0]

Hey Everyone -

Does anyone have a pic of a set of no number sandcast upper crank cases they can submit for evaluation. Looking specifically for a dealer swapped out set of cases, preferable changed after September 69.

Are there other cases out there with the letter T cast on the back of the upper case?

Thanks,
DW

[cb7504]

DW i have at least one set of late unstamped sandcast cases. I'll take a picture or two this week end and post them. Marty K.