Cool running

[pugster307]

Hi peeps,

A friend of mine has a 1992 ZXR400L which isn't warming up properly and i suspect a dodgy thermostat. I've been searching online for one but had no joy so far, does anyone know where i could one at a reasonable price, local bike shop quoted about 40 quid which i think is a bit steep seeing as one for a car is only about 6 quid.

Your help would be much appreciated thanks.

[cargo]

I doubt if it's the thermostat..................if it's stuck open the bike will still warm up............... slowly

And if it's stuck closed the bike will run hot....................

ZXR400s in my humble opinion tend to run with the temp guage at the low end of the scale

Maybe you should team up with the guys with the overheating ones

[RedexRobB]

Where does the temp gauge sit when its being ridden? It should be somewhere between the first line after the blue box and the very middle of the guage which is about normal running temperature.

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[pugster307]

Cheers for the reply's guys, the bike does warm up eventually but doesn't get much above the blue unless its running standing still, also it responds better to opening the throttle from idle when properly warm but still sluggish which i think is another problem like gummed up carbs, yet to have them off and clean them out.

[cargo]

Could be that the thermostat has been removed ! If you want a cheap solution try putting some tape on the radiator to restrict the air flow and it will run a bit hotter.

[Big Al]

hi all, had same problem with bike running too cool. cleaned radiator fins, flushed cooling system, cleaned coolant filter to carbs, changed thermostat and put new coolant in and purged as per the manual and guess what? YEP, IT STILL RUNS A BIT COOL! on normal road riding runs between first and middle marks, but on motorway drops to just below first mark. Fan cuts in just above middle mark on gauge. I suppose this is better than too hot (head gasket !!!!). Parts: Had to get thermostat from main dealer in end as couldn't track one down £38.00 ouch, but did come with new sealing gasket. Don't know why temp still fluctuates, thought thermostat was supposed to regulate it (yes, have put in round the right way). Maybe everything working a bit too well now? might tape over some of the rad to bring temp up a bit try keep in optimum range. Anyone got any other ideas would be appreciated. cheers.

[cargo]

Just about everything you did would help the bike run cooler.....................a clean radiator make for better cooling flushed and intrenally cleaned cooling system will help it run cooler...................yet you wanted it to run a little hotter.

Basicly you wasted a lot of time effort and money

[gavinfdavies]

buy a knackered old radiator with lots of bent fins, that'll keep you warm! on my gpz which has a stuck-open therm. when it gets cold i slips a piece of corrogated cardboard between the stone guard and he rad. seems to work.