Tri-Z Guys-Help! Radiator problems

[Tri-Z Pilot]

I dont really now if there is something physicalliy wrong, or it was an error on my behalf. After I rebuilt my tri-z (operation tri-z) I started it up, and it idled ok (after I fixed my high rev problem) I gave a couple quick pulls on the throttle cable (I need tri-z thumb throttle, got one?), and after a few seconds the overflow started spewing out coolant. I felt the cylinder and it was nowhere near warm (slightly), so does this mean my cooling system is ok and I just overfilled it? Whenever I take the cap of to look after it loses some coolant it looks like it is still at the same level, is this just because the liquid expanded? I need help, dont want to hurt my baby.

[TimSr]

This is caused by your head gasket leaking compression from the cylinder into the cooling system. A common cause beside a gasket or inadequate torquing is head warpage. I fixed mine by taping sandpaper on a piece of glass, laying the head on it, and and sanding until the head bottom was flat. The cylinder can be fixed the same way, but fortuneately cylinder warpage is a lot less common.

[wolfspider]

you could have just overfilled it, i just rebuilt my triz filled the :-D radiator, then came back the next day topped it up and it blew coolant out while riding, but now its at the proper level everthing is ok. i hope yours is just the same.

[Tri-Z Pilot]

So if I accidently overfilled it, the next time I start my bike up, and it squirts out the coolant again then stops, if I put my hand on the cylinder and it doesnt get real hot, my cooling system is working ok, right?

[TimSr]

It takes 15 psi to squirt coolant through the radiator cap out to the coolant overflow resevoir. There are two ways to get 15 psi. One is boiling your coolant, and the other is from the cylinder through the head gasket. If you start it, and it squirts coolant out into the resevoir when you rev it, when its not even hot, its not from overfilling.

You can normally check coolant flow with the radiator cap off, but it will also look like coolant is flowing if the head gasket is leaking and you are blowing some of your compression through the cooling system. It can be deceiving.

Start your bike, pull the overflow resevoir cap, and rev the bike. If air or coolant comes out the tube, youve got a head leak.

[Tri-Z Pilot]

This never happened before the top end was rebuilt, so I dont think the head could be warped, so should I check to see if all my cylinder/head bolts are tight, and if that doesnt work try the sanding the head trick?

[TimSr]

Yes, absolutely, recheck the torque settings on the head bolts first.

[J.D.]

This never happened before the top end was rebuilt, so I dont think the head could be warped, so should I check to see if all my cylinder/head bolts are tight, and if that doesnt work try the sanding the head trick?

No leak before rebuild eh? did you make sure to take the head bolts off in a pattern when you took the head off?

[Tri-Z Pilot]

Ya know what, I dont think that I did use a criss cross pattern when I took my head off, how boneheaded is that? Well, anyways its about 2pm, I am going to go mess with the beast, but I was wondering, could a bad radiator cap be the problem?

[Tri-Z Pilot]

Thanks for all the replies guys! It turns out that my problem was that my head bolts werent on tight enough. While I was letting the beast idle, I found a new problem. I have tranny oil leaking from underneath, right around where the cases meet (I think?), so I took my tranny oil check bolt out, and nothing came out (just filled yesterday). Next I put a good bit of oil in (about half to three quarters of what it takes to fill it up). Next I started the bike, and took the cap off to see if any smoke came out, I didnt really see anything (my nonexistant exhaust gasket smoke gets in the way), but the tranny oil started bubblin up and out, and it looked like chocolate milk (the tranny oil I get is a bright red-honda 250 oil), and I didnt even get to fill it up to the check bolt when I put oil in (not enough oil). Now correct me if I am wrong, but arent these the symptoms of bad main bearing seals?