2-stroke IT490 motor swap

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Mathius

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IT490 Warrior hybrid

So I haven't posted many pics of this thing around, but heres a few..

I have all of my mounts finally finished.. I just completed the rebuild of my 83' Yamaha IT 490 motor, and I got the swinger, and axle painted, and bolted on (just for mock up right now)
Things are starting to come together on it..
 

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LOOKIN guuud. That frame just primored?
Yah. Just for now.

I still have a few welds to finish up, and I have to make some mounts/hangers for my exhaust.

I'm just gonna paint the frame for this season though. If everything holds up good I'll tear it down this fall, and have it powder coated. (unless that paint really hangs in there?)

All that I have left to do to this thing is get the exhaust I have modified, and then I can start assembling it. :tup:
 
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Well it looks more like a quad every day.

Quad10.jpg
 
i got a 465 motor im planning on putting in and was wondering whats the dimensions u cut the swingarm out or wat mods r done that i need to do. thanks
 
i got a 465 motor im planning on putting in and was wondering whats the dimensions u cut the swingarm out or wat mods r done that i need to do. thanks

Well... First off I should ask if that old 465 is out of an IT, or a YZ? Some of the old IT motors were 5 speeds (mine is). I wouldn't run a 4 speed in a quad.. But to each there own.

As far as getting it in the frame it's fairly easy. I had to mock up the motor just siting on the swinger bolt, my motor sits way over to the left side of the frame. I had to do that in order for the sprockets to line up..
Then I just cut that section out of the swinger, and welded pieces back in till it looked good... lmao
(I did have to cut about a 1/2" inch into the left tubing on the swingarm. But I used a piece of 2" inch square tubing to brace the swinger, and hopefully keep it from flexing)

Then I welded in a cross piece at the bottom of the frame for the bottom motor mounts.. The rest was gravy after that.

I should also mention that a Honda TRX250R FMF Fatty pipe works quite well on these motors.. Just make yourself a head pipe about 13" inches long, and Voila!! They fit the frame really nice 2.. :tup:
I modded my stinger as well from 45mm, to 49mm. But I don't think you would have to worry about that on a 465..
 
any updated pics of this beast yet

I actually took this picture earlier.. It's a full roller now.

Quad11.jpg


I still have allot to do. Like clean, and paint the plastics, and rear wheels. But it's getting there.

I'm working on my head pipe right now, when I get the exhaust finished I'll paint the frame... Then I'll be able to post some video. :evilface:

Quad12.jpg
 
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I didn't think those old 490's were electric start... If not, and you had to slide the motor to the left in the frame for it to line up, how do you start it. Is there clearance for the kick start, or will it be a bump start only?
 
I didn't think those old 490's were electric start... If not, and you had to slide the motor to the left in the frame for it to line up, how do you start it. Is there clearance for the kick start, or will it be a bump start only?

I kinda made my own kick start.
I just heated, and bent the stock kicker to clear the frame.. Then heated it again, and cooled it in oil.
 
I kinda made my own kick start.
I just heated, and bent the stock kicker to clear the frame.. Then heated it again, and cooled it in oil.

That's cool...Grab a pic of the right side of the frame when you get a chance... I'm really interested in that...I love old 2 stroke bikes, bet a 490 on a Warrior frame would be absolutely awesome. If you can get traction, that is...
 
That's cool...Grab a pic of the right side of the frame when you get a chance... I'm really interested in that...I love old 2 stroke bikes, bet a 490 on a Warrior frame would be absolutely awesome. If you can get traction, that is...

Well I have it geared kinda high (14/38). With a 20" tire, at 7500rpm..
1- 2.666 = 23.5mph
2- 1.750 = 35.8mph
3- 1.315 = 47.8mph
4- 1.000 = 62.2mph
5- 0.785 = 79.8mph
I did that on a gearing calculator..
So I think the chances of it hook'n up are kinda slim.. Plus it's pretty light now.
But it should be fun.

It might be awhile before I actually post some more pics..
I hope to have the exhaust done this week, then I'm gonna tear it all down again for paint.
But once the paint is done I'll post some fresh pictures of it. :tup:
 
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well went out and shifted through the gearsand mine is a 4 speed is that yz or it, or did they both make 4 speed
 
well went online and typed in engine numbers 23x and found out thATS its a 1983 yz490k, has a 465 jug but looks bored out to the 490 piston, and its a 4 speed
 
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