Pulling the TZ250 motor

[Kennedy]

They look pretty.

[carl_g]

Cool pics..you can see the cross hatches from the honing.. looks good man!

[IrocRob]

Nice Ken - Be certain that the port edges are not sharp.
They look like they are good to go but verify that just to be sure.
It's hard to tell from the pictures.

I made that mistake once and had a piston ring shatter
on the sharp edge of a transfer port after building up an
entire Kawasaki 100 from scavenged parts back when I
was about 12...I remember thinking:
"What the hell just happened? oh well, it's still running so it can't be that bad."

[NYCSTRIPES]

Rob
it was the first thing I checked when the barrels came back. They did a good job of dressing the edges of the ports.
thanks
Ken

[FDNYDANO18]

Ay,
You start puttin her back together yet?

[NYCSTRIPES]

today it begins..

[NYCSTRIPES]

Got the motor completed today, just have to pressure test it. I put in a new clutch cover, new heads, replated cylinders, new pistons, bearings and some other stuff.
If I get the pressure testing done soon, I will fire it up and get it ready for the next track day.
Ken

[NYCSTRIPES]

Update.
I just got finished pressure testing the motor.
I have the left cylinder holding pressure at 6PSI. THe intake manifold was leaking air and it took a little while to find the leak. Now its A-OK.
The right one (forward cylinder) is leaking air into the cooling system. I pulled the head and re-sealed everything and checked the o-rings. Everything looked OK, but it still leaks. I have to pull the barrel now and check the base gasket to see that there is adequate sealant on the case/underside of the barrel.

I was also sent the wrong heads and I had to return them to RSCYCLES.com for an exchange. While I was at it, I ordered the replacements to be from a 2000 TZ125 and I am having Roland Cushway machine them for the TZ250. Looking forward to getting those installed on the motor at the next top end rebuild.

Tomorrow morning, I will be pulling the barrels again and re-checking the base gaskets and applying a little more Yamabond to everything. Sucks that I ran out of time today I have to head into work now. I am hoping that this takes care of the air leak. I would like to get the motor back into the bike this week so I can have my 250cc lawn mower back on the track soon.

Ken

[carl_g]

Originally Posted by NYCSTRIPES

Update.
I just got finished pressure testing the motor.
I have the left cylinder holding pressure at 6PSI. THe intake manifold was leaking air and it took a little while to find the leak. Now its A-OK.
The right one (forward cylinder) is leaking air into the cooling system. I pulled the head and re-sealed everything and checked the o-rings. Everything looked OK, but it still leaks. I have to pull the barrel now and check the base gasket to see that there is adequate sealant on the case/underside of the barrel.

I was also sent the wrong heads and I had to return them to RSCYCLES.com for an exchange. While I was at it, I ordered the replacements to be from a 2000 TZ125 and I am having Roland Cushway machine them for the TZ250. Looking forward to getting those installed on the motor at the next top end rebuild.

Tomorrow morning, I will be pulling the barrels again and re-checking the base gaskets and applying a little more Yamabond to everything. Sucks that I ran out of time today I have to head into work now. I am hoping that this takes care of the air leak. I would like to get the motor back into the bike this week so I can have my 250cc lawn mower back on the track soon.

Ken

It will be all worth it in the end!
I am pulling mine apart tonight... new bottom end is needed I fear.

[NYCSTRIPES]

Turned out to be my front cylinder base gasket. Some high heat silicone and that was it.
All buttoned up and ready to re-install.
Ken

[FDNYDANO18]

Nice one Ken!

Ride it well and in good health!
ps: wish I was going this weekend

[Cakes206]

Nice work Ken, can't wait to see this thing in action

[NYCSTRIPES]

I got the motor re-installed. I have to clean the carbs and set the ignition timing in the morning. Looking to fire it up tomorrow.


Ken

[NYCSTRIPES]

Originally Posted by FDNYDANO18

Nice one Ken!

Ride it well and in good health!
ps: wish I was going this weekend

Thanks.
I am headed out with Jeff Quinn Saturday. Hitting the Boxing match in Jersey City on the way home. My brother is fighting in a charity bout there. Oh and clear out yout AOL mailbox ..emails have been getting kicked back for over a week.

Ken

[JimRBlue]

I must say this is quite the interesting post! Never owned a 2 stroke nor realized the amount of work that can be involved with them. Excellent thread!