Cooling system bleeding...(need help)

[jbthumper]

Hey all...!!

does anyone know how to bleed the cooling system??because on some other bikes, they have this bleeding valve somewhere on top of the engine(head)..



thanks!!
cheers.

[DAVID THOMPSON]

did you mean drain or bleed as i can find neather any point to bleed or drain the system

i removed the hose at the very bottom of the front of engine.
I made an adapter that allowed a waterhose to be attached to the motor
i turned it on and flushed the system with the motor running
it may take a bit for the thermostat to open as i used hot water
i reattached the hose and with motor running refilled the system
with new fluid
be carefull of hot fluid and dont put too much in as highest level
is when full at the cap with motor off and cold
when its cold there is none or very little water in the hose from the thermostat to the top of the radiator

[jbthumper]

thanks dave,but actually i was thinking about bleeding it through the water jacket...
on a yamaha wr250 there's this bleed valve on the engine's head(for cooling system)...
it applies the same principle as a brake caliper...that is,the bleed valve is put at the highest point of the caliper...in this case,it's the head...

since the 125 engine doesn't have a bleed valve for the cooling system,i was wondering if i could use any other point/joints as a bleed valve...i just don't know which one...

[DAVID THOMPSON]

the 125 may not need to be bleed
it depends on how the water flows and the wr may need it to get air out of the system
my 125 seems ok

this 125 motor is the make or break for mz in the world market place
and other than the problems with the starter i think
they did a very good job with it's design

unlike the USA the rest of the world runs on 125cc bikes
and when you build one it better be good or the buyer will
go elsewhere

i have been riding 50 years this year and find a 125cc bike very usefull
for about 80% of my riding and the saxon tour 500cc fills in the rest
i use bikes as basic transport unlike most here
most riders here think any thing less than 750cc is a toy

the biggest problem i have is getting them started when the weather is below zero deg C

[jbthumper]

yeah,i guess you're right...


haha...but you guys don't pay as much import duties as some countries...and i think it really depends on every person's monetary status also to call any bike a toy...but hey,that's just me...


thanks anyway.

ride safely.

[micheleen]

I changed the coolant in my SM by disconnecting the bottom hose from the rad to the engine block (drained onto gravel as weedkiller ). then just filled it straight back up into the rad. I ran the bike a few minutes with the rad cap off and kept topping up till it stayed full then job done. Checked the coolant a few days later and it was still full so no bleeding needed IMHO.

Cheers, Mike