Radiators? Whats the verdict?

[kw86er]

My 1KT radiator is in working order but looking at some info here and YPMRC they are not quite big enough? I almost sprung on a KR1S rad on eBay that Was a good price but after closer inspection it was identical to mine and not like others I had seen in pictures. I messaged the seller and he said oops your right! Close call what if it was sent all the way from the UK to Canada?

So are the Chinese rads any good, any bigger? What are the options. Or should I just stick with what I have?

I ride pretty hard and have a property in the desert where I ride quite often. No major tuning besides Jolly's.

[LCRacer]

Big question is how does the bike run with the stock rad, if it's not getting hot then you have nothing to worry about IMO

We run bigger rads in YPM because of a higher state of tune. More compression and higher revs equals more heat. The bikes are flat out through the gears for a fair amount of time as well. Gets hotter the bigger the bore too.

The rad of choice used to be the more efficent KR1s, horizontal plane rather than vertical, but RGV 250 (needs a fair amount of fabbing to get it to fit), NSR MC18 and latterly the Suzuki LTZ400 (chineese alloy) rad have been used. The R6 rad is a decent fit but there is some welding fabrication to get the filler in the right place I believe. None are a bolt on fit.

Most of the upgraded rads that are sold for the TZr seem to add no benefit from our experience, hence the adaption of other rads

You can also get a lower temp thermostat, off a Yamaha snowmobile that helps things, or the old skool trick used to be to take the guts out of the thermostat completely leaving the outer.

[kw86er]

Cool good to know. I have never ridden this bike and currently fitting allot of stuff. Figured it was as good a time as any if it was need but sounds like I will be fine with stock. Thanks for the quick reply!

[tzr-v4]

I'm using a curved radiator from TZR 125 4DL similar to 3MA one.
I'm not using OEM style fairing but TZ250 one so I don't know if there is an issue with OEM fairing.

[kw86er]

I will be using the early 90's TZ fairing. Good to know I will keep my eyes pealed.

[tzr-v4]

TZR250 2XT radiator is bigger than 1KT

4DL one fitted
http://rd500lc.free.fr/tzr-250-2xt/tzr250-2xt_en.htm#6

[LCRacer]

Cool good to know. I have never ridden this bike and currently fitting allot of stuff. Figured it was as good a time as any if it was need but sounds like I will be fine with stock. Thanks for the quick reply!

No problem. The stock rad is marginal on a race bike, but there are plenty still running it. I think it's probably worth upgrading if you live in hot climates and intend to ride the bike as it should be ridden :-)

[4l04ever]

Fit a digital thermometer and see what temps yuou are getting, then you know if you need to upgrade or not.  55 degrees C is perfect if you can get it....

[Jim Lyon]

Fit a digital thermometer and see what temps yuou are getting, then you know if you need to upgrade or not.  55 degrees C is perfect if you can get it....

Yeh, this is NOT a bridge you have to cross until you come to it. Yeh, get a more accurate digital temp. gauge, then when you more accurately know what your actual  operating REALLY is, then make a decision !

[LCRacer]

55 degrees C is perfect if you can get it....

Actually with the ethanol tainted sheeps piss we have to call petrol these days I've been looking to run the bikes a bit hotter, certainly they run cleaner and show a marginal power increase, I've been looking for 65 defgrees C

If yo are lucky enough to have decent fuel then indeed 55 degrees is the aim 

[mboddy]

I used the Chinese radiator this weekend at the International Festival of Speed.
The bike ran way too hot.
So I will be refitting the Chinese 40mm RZ350 radiator that I modified to fit the bike.
It was always good for keeping the temp around 60 degrees C.

[tzr-v4]

TZR250 2XT radiator is larger than the 1KT / 2MA one.
I'm using TZR125 4DL one (similar to 3MA one) on my track bike (2XT) and last Monday on Pau arnos Track the temperature stays below 60°C but air temperature was between 10-15°C.

nice twisty track with up and down hills
http://www.circuit-pau-arnos.fr/circuit-de-vitesse_1_1_2.html

[James P]

TZR250 2XT radiator is larger than the 1KT / 2MA one.

If you want to go this way, you may find the 3XC (R1-Z) radiator a little easier to obtain - it is nearly identical to the 2XT radiator: http://pure2strokespirit.net/forums/index.php?topic=4477.0

Regards,
James