hairline crack on the engine mount

Wheels, shocks, forks, frame
Post Reply
dirk
Heavy Smoker
Posts: 322
Joined: Mon Jul 30, 2007 8:18 pm
Location: Germany

hairline crack on the engine mount

Post by dirk » Mon Sep 09, 2013 9:38 pm

Hi folks

I find (again) a hairline crack on the engine mount. :(
it has been welded.
what is the cause?
how did you do that?

Image

regards
Dirk
TZR250 (2MA) 1987
KR-1S 1990
RG500 1987
RGV 250 1992

User avatar
JanBros
Premix Junkie
Posts: 2913
Joined: Wed Jul 26, 2006 11:50 pm
Location: the land of Francorchamps
Contact:

Re: hairline crack on the engine mount

Post by JanBros » Mon Sep 09, 2013 10:07 pm

tolerarances for the spacer are too big. it will need welding again, and then you'll need to shim the spacer (or make a new one) so that it just fits in between.

yours has too much play, so when bolting it together, it bends and has to endure too much stress.
You know it's cold outside when you trip over dog shit instead of standing in it.

dirk
Heavy Smoker
Posts: 322
Joined: Mon Jul 30, 2007 8:18 pm
Location: Germany

Re: hairline crack on the engine mount

Post by dirk » Tue Sep 10, 2013 9:57 am

Hi Jan

thanks for the reply.
i can remember that the engine was mounted without play.
the spacer was specifically designed.
is there an aluminum alloy which is a bit more flexible?
maybe there are indeed fine vibrations that cause the crack?

regards
Dirk
TZR250 (2MA) 1987
KR-1S 1990
RG500 1987
RGV 250 1992

User avatar
JanBros
Premix Junkie
Posts: 2913
Joined: Wed Jul 26, 2006 11:50 pm
Location: the land of Francorchamps
Contact:

Re: hairline crack on the engine mount

Post by JanBros » Tue Sep 10, 2013 3:46 pm

who did the welding ? it doesn't look like a pro did yours. those tiny little holes on the surface mean there will be also like those on the inside and they are weak spots. a good welder doesn't need to grind the welds away, a good weld is nice to see.

I also have to grind my alloy welds away :cry:
You know it's cold outside when you trip over dog shit instead of standing in it.

dirk
Heavy Smoker
Posts: 322
Joined: Mon Jul 30, 2007 8:18 pm
Location: Germany

Re: hairline crack on the engine mount

Post by dirk » Tue Sep 10, 2013 10:29 pm

Thanks for your explanation


the welder is master mechanic.
i myself have have no idea of welding.
i do not see it whether it is good or bad :oops:

dirk
TZR250 (2MA) 1987
KR-1S 1990
RG500 1987
RGV 250 1992

dirk
Heavy Smoker
Posts: 322
Joined: Mon Jul 30, 2007 8:18 pm
Location: Germany

Re: hairline crack on the engine mount

Post by dirk » Tue Apr 14, 2015 11:04 am

Hi All

So here is the second attempt .....
does not look nice, but I hope it no longer breaks.

Image

regards
Dirk
TZR250 (2MA) 1987
KR-1S 1990
RG500 1987
RGV 250 1992

dirk
Heavy Smoker
Posts: 322
Joined: Mon Jul 30, 2007 8:18 pm
Location: Germany

Re: hairline crack on the engine mount

Post by dirk » Fri Apr 17, 2015 12:20 pm

step 2
a new spacer.
the original spacer was 25mm long.
it lacked 1mm
after welding the engine mount has moved 0.5mm to the outside.
the holder on the engine itself is only 7,45cm.

Image
TZR250 (2MA) 1987
KR-1S 1990
RG500 1987
RGV 250 1992

Post Reply

Who is online

Users browsing this forum: No registered users and 2 guests