Author Topic: question about casting holes on engine case/Hondaman and guru's  (Read 670 times)

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Offline paddy paul

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 I was having my morning coffee, looking at my 750 and got to wondering what are the holes that are cast into the upper and lower case for, on the right side by the front motor mount  there is one that is also cast into the upper case on the left,  it allmost looks like there should be a bolt in it, is this part of the casting process, for a mount that they never used,  custom Honda engine stand? anybody have an idea.

Offline Mark M

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Re: question about casting holes on engine case/Hondaman and guru's
« Reply #1 on: March 13, 2011, 10:40:06 AM »
Production line lifting mounts?
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DH

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Re: question about casting holes on engine case/Hondaman and guru's
« Reply #2 on: March 13, 2011, 12:17:21 PM »
Alignment dowel hole for the upper and lower case halves? (one on the right)
« Last Edit: March 13, 2011, 12:23:04 PM by DH »

Offline 754

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Re: question about casting holes on engine case/Hondaman and guru's
« Reply #3 on: March 13, 2011, 08:34:00 PM »
 I think they are index holes for when the cases are machined..
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Offline CycleRanger

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Re: question about casting holes on engine case/Hondaman and guru's
« Reply #4 on: March 13, 2011, 08:41:31 PM »
I think they are index holes for when the cases are machined..

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Offline 754

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Re: question about casting holes on engine case/Hondaman and guru's
« Reply #5 on: March 13, 2011, 09:05:28 PM »
 If I remember right , Honda bult machinery to do the 750 case machining in 1 process..and were the first in motorcycling to do so..

 Raw cases go in, finished sets come out.. all  or most perfect.. very low rejection rate..  It may be a combo of machines with transfer stations between so no human handles it. It may be called cell manufacturing and was a very early application of it.

 Probably went in use when they got the first diecast cases..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline paddy paul

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Re: question about casting holes on engine case/Hondaman and guru's
« Reply #6 on: March 14, 2011, 05:57:52 PM »
thank you,