ST1100 coolant replacement odd procedure

Given this information, I moved to a partial replacement method years ago and it has stood me well, never had any coolant issues on anything I own. So here it is: Whatever the recommended coolant change interval is, cut it in half. That is the new change interval. Pull off hose, open valve, etc. at the lowest point you can find in the system. Whatever drains out, drains out. Close up system, re-fill with fresh coolant, burp system, run engine, etc. check for leaks and return to service.

Every cooling system I've ever seen will dump at least 60-70+% of its volume just by removing the lower hose, or draining at the lowest point. When I've been able to I measure what is drained, I compare it to the capacity specifications its always been most of the coolant in the system. The more frequent change cycle more that replenishes the additive packages, and I'm convinced the new silicate-free coolant formulations make flushing a relic of the past. When I do have to crack into a cooling system, they have been clean as a whistle inside, so it appears to work.

I realize this is anecdotal, and goes against conventional wisdom, but I've done it successfully for a couple decades on multiple vehicles, some of which now have 330+K on the odo.

YRMV, don't try this at home, etc.

That's what I've done also for many years. No problems....
 
I don`t know the internal layout leading to the two drain bolts .Part of me thinks the bolts on both sides will be a simple cross connection but having flushed the brown mess from the right side I will take out the left side bolt and flush the water out of there too . Always remembering to use an open ended spanner as the bolt gets out far enough to jam my ratchet spanner against the frame . My ratchet has to be turned around to work in reverse . The extra long 10mm spanner I ordered has no ratchet . It`s enough to get the bolt started . There is a difference between flushing out and just draining so I treat it all like the radiator .
 
Here is my plan. When I quit procrastinating and change my blown left side head light bulb I'll change my coolant too. Since I'm removing the windscreen and other associated parts I will have room to use my Lisle spill proof funnel. Should make burping and getting the air out of my cooling system easy peeze.
 
When the plastic drain plug on the radiator is removed you get some coolant out .Not all of it . So taking off the bottom hose lets a bit more out . Then some more if the 2 bolts are removed . Is there going to be some left inside? Does the brass thermostat prevent coolant from being released until the temperature is right ? I feel as if something has never been explained about this engine . Don`t forget the overflow bottle on the side . What liquid quantities have to be used for a full change ? Is that amount less than the total inside the engine .Always allow the engine to cool down before adding cold coolant . I think that rule still applies .
 
I managed to slacken the left side bolt with a copper pipe extension on the spanner. The starter motor does not allow any proper movement for a spanner . I had to encourage the bolt to turn with a sharp spike as spanners in that position are useless . Clock that up as a definite Honda design fault . The bolt is lined up exactly behind the exhaust pipe but if you take off the heat shield there will be room for a screwdriver to work , so I will cut one slot in the bolt before it goes back in . That`s when I can find the bolt . I had to get a tiny mirror to see where it landed when the water pushed it out. It`s lodged just opposite the bolt hole but bits of bent wire can`t get it out .So I will use a small magnet on some masking tape to hold onto it . The exercise of removing the left bolt was a waste of time as hardly any dirt was washed out . Just use the right side bolt and forget the left one . Well somebody had to do it .
 
The left side bolt mysteriously disappeared .I had a 3ft wide yellow plastic bowl used for mixing cement underneath the bike. I swept the floor .No sign of the bolt . I got a replacement bolt and it slipped out of the spanner .That disappeared too . I dangled some strong magnets in the space . No luck . Nothing on the floor. The starter motor is just underneath the bolt hole. I think the starter has a strong magnet and it must be holding onto the 2 missing bolts .My third attempt with a cardboard strip and a cross cut to hold bolt number three was a success . But damn it to hell and back . Now the 2 bolts have slots cut in them for a screwdriver . Just nip them up with a spanner at the end .
 
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