1990 KX 250 fix up.

Micahdogg
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Micahdogg 12/4/2015 1:17pm
12/4/2015 1:17pm
Yes, freezing will split, but its much less effort to fix a split (usually an inch long) than pull all those dents out.

Last time I used compressed air, I was up to about 120 psi.
SOHC
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SOHC 12/4/2015 10:18pm
12/4/2015 10:18pm
Micahdogg wrote:
Yes, freezing will split, but its much less effort to fix a split (usually an inch long) than pull all those dents out. Last time I...
Yes, freezing will split, but its much less effort to fix a split (usually an inch long) than pull all those dents out.

Last time I used compressed air, I was up to about 120 psi.
Yes I had my pipe at the same pressure as the compressor and it wouldn't pop out, then I burnt through and the air blew a big hole like a cutting torch.
SOHC
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SOHC 12/7/2015 12:12pm
12/7/2015 12:12pm
What should the piston to head clearance be?
RyanLester761
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RyanLester761 12/7/2015 9:43pm
12/7/2015 9:43pm
SOHC wrote:
What should the piston to head clearance be?
I believe 0.7mm ~ 1.0mm clearance will do (Approximately .030"-.040"), but don't quote me on it.

The Shop

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SOHC
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SOHC 12/8/2015 11:48am
12/8/2015 11:48am
I got 0.43 when i did the solder trick.
SOHC
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SOHC 12/8/2015 10:32pm
12/8/2015 10:32pm
Where should I set the timing marks for the stator plate? i see it has one line on the case and 3 on the plate,

Or should I run it and keep advancing the timing till it pings and back it off till it goes away?
SOHC
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SOHC 12/9/2015 11:56am
12/9/2015 11:56am
I have to take the cylinder head and get it cut deeper on the squish as the head has been planed at some stage and I had the cylinder decked when it was re plated.
SOHC
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SOHC 12/11/2015 10:38pm
12/11/2015 10:38pm


You can see on my head the step from the gasket face to the squish band is hardly visible, but looking at the other heads on ebay I can see they have more of a step.
SOHC
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SOHC 12/11/2015 10:45pm
12/11/2015 10:45pm
This is a pic i found, look at the step,
SOHC
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SOHC 1/24/2016 10:05pm
1/24/2016 10:05pm
I have been waiting nearly 10 weeks for my pipe from Canada to come, it may take moths more I am told.


I have removed the cylinder head and it is away being recut by a friend, other than that I am saving up for a clutch kit and chain and sprockets.
SOHC
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SOHC 1/26/2016 12:10pm
1/26/2016 12:10pm Edited Date/Time 8/10/2016 9:12pm
My friend was able to grip the head in the big 4 jaw lathe.

This is the worst head to try and do anything to the combustion chamber, it has an offset plug hole that is at an angle and its not round.



SOHC
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SOHC 2/15/2016 8:16pm
2/15/2016 8:16pm
my PC works pipe got here



I will work the dents out and put it on.
SOHC
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SOHC 2/16/2016 11:50pm
2/16/2016 11:50pm


SOHC
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SOHC 2/16/2016 11:54pm
2/16/2016 11:54pm
After repair, I used 50 to 60 PSI and the oxyacetylene to pop the dents out, made a tool form an exhaust clamp and bit of 3/8 plate, you need to get the dents very hot is the section close to the engine,


RyanLester761
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RyanLester761 2/17/2016 5:39am
2/17/2016 5:39am
Good job on the pipe!

As far as the stator timing marks; I would set it to the middle line and see how it runs.
SOHC
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SOHC 2/17/2016 12:44pm
2/17/2016 12:44pm
RyanLester761 wrote:
Good job on the pipe!

As far as the stator timing marks; I would set it to the middle line and see how it runs.
I am pretty happy with the pipe.

Will trt the timing mark in the middle, I understand advancing and retarding the timing on a 2 stroke is way different to a 4 stroke
SOHC
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SOHC 2/18/2016 6:39pm
2/18/2016 6:39pm


SOHC
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SOHC 3/13/2016 1:18pm
3/13/2016 1:18pm Edited Date/Time 3/19/2016 11:51pm
New clutch friction plates arrived, steels on order

Pit Row

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SOHC
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SOHC 4/11/2016 2:45pm
4/11/2016 2:45pm
Been riding round a bit now, goes very well, I have destroyed the rear tire riding on the road

SOHC
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SOHC 5/3/2016 1:20am
5/3/2016 1:20am Edited Date/Time 5/3/2016 1:21am
..
SOHC
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SOHC 5/15/2016 1:52am
5/15/2016 1:52am

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SOHC
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SOHC 5/15/2016 2:01am
5/15/2016 2:01am Edited Date/Time 8/10/2016 9:32pm
I sold it today at a huge loss, anyway I needed some money for a trip and I am to sick to ride it

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