So I am new to the thumper

I just purchased a 99 YZ400F this past weekend. Its a very low-hour bike, all stock except for front/rear springs. I have been reading many of the post in this forum and it is calming my fears about the bike. I have the typical flaming hot header pipe and some exhaust popping on deceleration (very little, but some). The bike runs great and has plenty of power. I switched from a 2-stroke 250 to this so I could ride more with my young son and not worry about fouling plugs. The problem I have now is that when I am putting around with him, it feels like there is a campfire between my legs. Should I worry about overheating this thing if I am riding around in 1st gear with my kid?

The problem I have now is that when I am putting around with him, it feels like there is a campfire between my legs. Should I worry about overheating this thing if I am riding around in 1st gear with my kid?

A campfire? :lol:

YZF's require a lot of air passing thru the radiators to keep it cool. If you must putt around, then you should use a product like Engine Ice or Red Line Water Wetter for the radiator. There is another product called 2twocool (TT store has it) that lowers the engine temperature quite a bit. I'm doing my own testing with the 2twocool and will do a right up on it in the near future, but for now, I can tell you that it works as advertised.

Welcome to TT. :thumbsup:

I had that same issue and I used the pink stuff (water wetter) and it helped out a lot with the problem. I also replaced my radiator cap with an after market 1.6 psi cap from Pit posse.

The cap helps keep the radiator fluid in the radiator and the water wetter keeps the engine from overheating.

Engine Ice works too and it is on sale at cycle gear for $16.99.

I hope this helps!!!!

Patrick M.

you will never look back owning a YZF :banana:

What about coolant overflow tanks, anybody try adding one?

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