Bimota SB8R Project Bike. Part Thirteen: Can The Cooling System Be Saved?

"Huston We Have A Problem". The cooling system was hiding some major issues. Time to dig in and see what is salvageable. Honestly slightly worried.

1w ago


So this was meant to be a much more of a positive update. In one of the last updates I talked about putting new tires on the bike, and those that have been following along know that I had already gotten the bike running. Once the tires were on there really was nothing stopping me from taking the bike for a ride.

The feeling of getting a bike like this out on the road is amazing, until it is'nt.

To say that I was excited would be an understatement. Sure the bike had put up a little bit of a fight, but all and all it was about an average amount of work and money to get the bike to this point. I let the bike warm up on a stand for a bit. Checked everything over for leaks and odd noises. After everything was confirmed to be good, the only thing left was to put it in gear and see how see goes down the road.

It was glorious. Really like nothing else I have ever ridden. The best word I can think of to describe the way the bike feels, is tight. Not harsh, or stiff. Not darty like my SB6R.

I was keeping a close eye on the gauges and watching the temp rise and fall as speed built. When at a light the bike would get hotter. Not hot, just hotter. This is a totally normal thing with full fairing bikes. What did strike me as odd is how much the temperature was fluctuating. It seemed to gain and loose 40-50C at times. My first assumption was a failing sensor. I had proved that the bike would move under it's own power, it was now time to take a look at the sensors.

I had also stopped to fill the fuel tank. It was at this point that my heart sank. I started hearing an alarming ticking sound. I was only about half a mile from my house, so I limped it home. Was thrilled to find out that name TL was given to these motors by Suzuki to stand for "Ticking Loudly". In much the same way that a Ducati dry clutch sound scares new riders, this TL sound was nothing to worry about.

Anyone remember when I mentioned the perished seals on the radiator cap? Well I should have looked into things then. The whole coolant system was filled with particles. Some rust, some hardened coolant, others just looked like sand and rocks.

I am not starting to understand that the temperature readings were correct, it was just coolant was not flowing predictably or correctly. Some of the hoses were completely blocked.

Took everything apart for a deep clean. Found some issues. The water pump cover was rusted, as was the cross over pipes from the cylinders.

Good news is that the three, yes three, radiators seemed to clean out well with fresh water. I see no evidence of leaks or damage.

Gaining access to the thermostat was less then ideal, but packaging is never a strong suit on a superbike.

Lucky for me, most of these parts should be Suzuki OEM, or so I thought. It seems that Suzuki is no were near as good at stocking parts for older bikes as Honda is. I was greeted to a couple of no date back orders and lead times that were weeks, not days for simple seals. At this point I think I have pieced together a couple of orders that should cover everything I need.

I will say that I am slightly worried that some of the internal coolant passageways are blocked. Unsure how I will deal with that. Sounds silly to have to disassemble a motor to clean coolant passages, but the last thing I want to do is over heat the engine and cause damage.

Right now the bike is just sitting in the back of the garage waiting for parts to show up. Missing out on some beautiful afternoon rides.

Might try one of those coolant flush kits. What do you guys think?

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Comments (5)

  • I would consider SeaFoam-

    some mechanics will swear by it.

      8 days ago
  • You may want to use a pressure washer, spray it through the inlet or the thermostat opening to flush the internal chambers. It will loosen any gunk if there is any and you will see it coming out if there are any blockages. Best of luck, beautiful bike !!

      8 days ago
  • I personally have never used one. So I can't say whether they work or not.

    In other vehicles, the cost of a new radiator is less than it would take to have an old one cleaned. On an imported sportbike, not so much!

      11 days ago
    • So far the radiators cleaned up well. I can get new ones, but they are like $300 each.

        11 days ago