So lately my bike started overheating.

I thought the radiator filter was dirty, or needed more coolant so I took it to a shop.

The mechanic said I had a liitle hole on it (maybe a stone hit it) so when the bike heated, the gas scaped through it..

And the solution was to replace the whole radiator (+300€ new) because for this model you cant weld it.

I really dont know about this kind of fixment.

enter image description here

In the picture I show where is supouse to be the hole.

Is the mechanic solution right? is there any other way to solve this?

  • In my day, you didn't weld radiators, you brazed them. Try that. Also, if the hole is small enough, use Radweld if that is still on the market.
    – Chenmunka
    Mar 1, 2017 at 16:17
  • @Chenmunka excuse my english, whats the difference between weld and braze? my translator outputs the same
    – lois6b
    Mar 1, 2017 at 16:19
  • Welding is mostly used for steel / iron. Brazing is for copper / brass. Soldering is for tin / gold / silver. The temperatures of each are different due to the melting points. For your radiator, is it aluminium? could be welded if so, but needs to be someone experienced in welding aluminium otherwise you get a big hole!
    – Solar Mike
    Mar 1, 2017 at 16:50
  • @SolarMike ooooh I get it, hahah in my language we have just one word. thanks for the info.
    – lois6b
    Mar 1, 2017 at 16:52
  • 1
    Looking at your image, then a long time ago we would crush the tube and braze or solder it to stop the leak. Now however, the tubes are so fine and the radiators so close to the minimum size that it is not advisable. Sorry, start saving...
    – Solar Mike
    Mar 1, 2017 at 16:57

1 Answer 1


You might be able to braze the radiator and fix the hole, but it depends on how big it is and where it is. Would be worth finding a few repair places nearby and checking with them. Send good quality photos with something like a coin for scale so they can get an idea of the damage.

It might be easiest and cheapest to just replace it. Check local bike breakers or online for a used radiator. You should be able to find one for a reasonable price.

Avoid the temptation to use the "leak-fix-in-a-can" solutions at auto parts stores. They'll make a mess of your cooling system that will be impractical to ever reverse.

  • thanks for answering. with "leak-fix-in-a-can" you mean the Radweld product recomended in the comments ?
    – lois6b
    Mar 2, 2017 at 8:50
  • 1
    Not familiar with that one specifically, but those are the types of products I was referring to. Your coolant system has lots of little passages all over the inside of the engine. If something does gunk it up, you're not going to get it cleaned out.
    – raydowe
    Mar 2, 2017 at 9:27
  • I read a bit more and it seems that the liquid "leak-fix" just react in contact with air, so maybe internal passages are not involved... can this be true?
    – lois6b
    Mar 2, 2017 at 12:19
  • 1
    That's the idea, yes. You mix it in with your coolant, and when some of it leaves the system at the leak, it reacts with air and solidifies. The problem is if you ever get air in your system, or it doesn't do what it's supposed to do, and some of it solidifies inside the system. It's very easy to degrade the system's performance, or block passages entirely. If this happens, there is no way to get it out. I know the idea of fixing this for <$10 is tempting, but the old adage applies here. "If it sounds too good to be true, it probably is."
    – raydowe
    Mar 2, 2017 at 13:58
  • The only time I would use something like this is if it's a really old vehicle, and you don't care about it. It will give it a little more life before you bring it to the wreckers. With a little legwork, I'd expect you to be able to get a good used rad for $50-100, which is a much better solution.
    – raydowe
    Mar 2, 2017 at 14:05

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