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Discussion Starter · #1 ·
Courtesy of Johnny O - Australian Motorcycle Importers

"To bleed the system: after topping up the radiator, with the cap off, lean the bike as far as you can to the left (just before the fairing touches the ground) then stand it up and top up the radiator, then lean the bike as far as you can to the right, then stand it upright and then top it up again. As you lean the bike over you will hear the trapped air rising to the top.

Also make sure that the radiator cap is 1.4 pressure and the seal 25mm as the older and smaller 22mm seal will allow leakage".

Senior Member
5,963 Posts
Bleeding a Tornado Radiator

There are other ways that don't require two people.
The problem with the Tornado cooling system is that there are two places that are natural airlocks.
  1. The easiest to deal with, alone, is the hose from the radiator to the pump. It runs over the alloy join between the left and right side of the frame. Squeezing that hose will eject the trapped air towards the radiator.
  2. The hardest is that at the thermostat housing. The coolant is below that both coming and going. The thermostat has a bleed hole which allows air trapped on the engine side to pass to the highest point, on the radiator side, but that doesn't help much when it feeds into another airlock. There is a degas hose that runs from the downstream side of the thermostat to the radiator cap, but it only works to draw out trapped air when the engine is running
The idea of rocking the bike from side to side is to move the airlocks towards the radiator. While better than nothing, it isn't that successful.
Some workshops use a hoist to lift the tail high enough for the airlocks to move back to the radiator, and out, but that is not practical in the average garage.

The first single handed solution I found involved a vacuum pump, which sucked the air out of the airlocks. No mods to the bike are necessary, but a vacuum pump, a modified radiator cap and some hoses and catch tank are.
The most recent method requires a mod to the bike, but little other equipment. I mentioned the degas hose above. For this method that hose must be removed and the nipple under the radiator cap sealed off. A short piece of hose with a stopper in it will suffice. A new hose is added at the thermostat housing which leads to the right side of the frame just above the engine, but inside the fairing. That hose has a brass stopper in it, with a nylon washer & M3 screw to seal it off. It becomes the bleeder. Attach a clear hose to the end of the bleeder (with the screw removed) and take it higher than the radiator cap, then down to a catch bottle. As you fill the system from the cap, the coolant will rise until it appears in the clear bleed hose. As air escapes, it bubbles up through that hose. Squeezing the radiator outlet hose will eject air from that airlock to the radiator. When no more bubbles show up, the system is airlock free and the bleed hose can be resealed.
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