Author Topic: motor swap  (Read 1909 times)

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Offline TT5 Matt

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motor swap
« on: February 02, 2013, 10:59:42 pm »
one for the yamaha brains trust. will a monoshock dt400 motor fit into a dt250a frame?im going to use it for flat tracking on my farm so airboxes/up pipes etc wont be needed.

Offline JAP 454

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Re: motor swap
« Reply #1 on: February 03, 2013, 06:55:38 am »
With a little bit of shed ingenuity, yes. My bike, DT250 frame, YZ 400E donk, from the '80s



Foss
« Last Edit: February 03, 2013, 06:57:44 am by JAP 454 »

Offline JC

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Re: motor swap
« Reply #2 on: February 03, 2013, 09:30:04 am »
From memory, the front engine mounts are slightly diff - one engine is slightly longer than the other

Offline JAP 454

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Re: motor swap
« Reply #3 on: February 03, 2013, 09:37:57 am »
Yeah, that'd be right, JC.
From memory, the front engine mounts are slightly diff - one engine is slightly longer than the other
I remember having to shift engine mounts around a bit, can't remember which ones, also I don't know if there is any difference between the YZ 400 and DT 400 engine mounts.
Foss

Offline Iain Cameron

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Re: motor swap
« Reply #4 on: February 03, 2013, 12:26:09 pm »
the 76 yz 400 will bolt straight in to the 73/74/75 frames , the 77 yz 400 will require the front eng mounts changed as the bolts are closer together . Iain
Yamaha tragic ; dt1, rt1, dt2, rt2, dt2mx , rt2mx , mx250, mx360,sc500, 74dt125, yzx125, yzc250, yzc400, yzd250, yzd400, yzh250, yzh80 , dt100 , xr75 ko xr80 03 , it175 82 . Not a member of any club

Offline TT5 Matt

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Re: motor swap
« Reply #5 on: February 03, 2013, 02:08:04 pm »
ok guys thanks for the answers. making the front engine mounts shouldnt be too hard to do ;D

that pipe on your bike JAP 454 was it a good thing and if you still have it would you like to share its dimessions so i can have ago making one at the metal fab homer course i do at tafe?

Offline JAP 454

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Re: motor swap
« Reply #6 on: February 03, 2013, 02:38:34 pm »
Matt, I don't still have any bits of that bike , but my brother Jim, jimg1au on this forum, knows the bloke who made the pipe, so he may be able to help.
However,this was back in the '80s
The motor and the pipe were originally used in a Single Cylinder Road Race class by Jim. It was pretty quick on the tar and wicked on Dirt Track.
Foss