Chinese oversized radiators?

[oldskool]

Has anyone had any experience with these 'made in china' alloy radiators? Do they do as they claim? ie: 25-30% cooler engine temp.
From what I can see they have wider vanes which are double sided. How is their fitment and build quality? My factory coolant capacity is 1 ltr. Is it safe to say the fluid volume will increase to 1300ml with an oversized rad?

[flyingcr250]

you should try one of those boysen high volume water pumps http://www.btosports.com/p/BOYWAT

[oldskool]

you should try one of those boysen high volume water pumps http://www.btosports.com/p/BOYWAT
Don't know if increasing the flowrate will help. The water churns through already. Actually wondering if I need to put a restrictor on the output end of the radiator. Water Wetter does diddly squat. Haven't tried a 1.6/1.8 bar cap yet...damn they're expensive for what they are!!

[barty5]

one of the yzfs we had last year had them they seamed ok cant say what the volume diff was just filled up sorry

[noobi]

The rated 25-30% increase, is a chinese measures so I wouldnt guarantee they will be 250-300ml greater capacity. Although its possible.
You also need to consider that increasing the capacity will most probably affect the fitment, so be aware of that.

Increasing the flowrate will help, although you need to be moving for it to make a difference.

[oldskool]

The rated 25-30% increase, is a chinese measures so I wouldnt guarantee they will be 250-300ml greater capacity. Although its possible.
You also need to consider that increasing the capacity will most probably affect the fitment, so be aware of that.

Increasing the flowrate will help, although you need to be moving for it to make a difference.

Thanks Noobi.
I've read in an earlier post Scott makes mention of a cheaper aftermarket 1.6 cap MR MX supplied other than the standard Kwaka 1.6. ....I've read elsewhere Kwaka supply 1.6 caps as standard on their machines, KTM 1.8, Yammy/Suzi/Honda 1.1
Do you know if you have any in stock?

[dafydd roberts]

Has anyone had any experience with these 'made in china' alloy radiators? Do they do as they claim? ie: 25-30% cooler engine temp.
From what I can see they have wider vanes which are double sided. How is their fitment and build quality? My factory coolant capacity is 1 ltr. Is it safe to say the fluid volume will increase to 1300ml with an oversized rad?

Yes they do hold more fluid, we was going to bring them in and sell to dealers but they are a bit rough and sometimes the sides are shaped to the point they look bent. From what I remember the CRF250X ones held about 150ml more each side than stock it could of been more but it was about two years ago now.

Also the plastics shrouds do not always mount up flush with the holes in the rads.

[oldskool]

Yes they do hold more fluid, we was going to bring them in and sell to dealers but they are a bit rough and sometimes the sides are shaped to the point they look bent. From what I remember the CRF250X ones held about 150ml more each side than stock it could of been more but it was about two years ago now.

Also the plastics shrouds do not always mount up flush with the holes in the rads.

Thanks Daf,
This is the one I am looking at. It seems reasonably priced and a lot cheaper than the other alternative in Oz.
http://www.trademe.co.nz/Browse/Listing.aspx?id=524810211
It's almost worth the punt for that price. A 20~30 psi rated bike rad cap would set me back close to $50 which is really a stop gap measure. Car caps are easy to find up to 16psi and are heaps cheaper but its hard to find one rated at 20psi.

[meteor]

I put one on a KX85. From memory it cost $140 landed here with hoses (3). Quality seemed ok from new but fitment wasn't perfect and the plastic air flow fins seemed to rub on it which over about 4 - 6 months rubbed a hole in the alloy. I went back to the company (through ebay) and with an exchange of photos a new one was sent free of charge. In comparison at that time a new one was around $450 and an aftermarket one similarly priced. Get what you pay for I guess... It was slightly bigger, I think the base under the fins was about an inch deeper. Hope that helps.

[dafydd roberts]

Thanks Daf,
This is the one I am looking at. It seems reasonably priced and a lot cheaper than the other alternative in Oz.
http://www.trademe.co.nz/Browse/Listing.aspx?id=524810211
It's almost worth the punt for that price. A 20~30 psi rated bike rad cap would set me back close to $50 which is really a stop gap measure. Car caps are easy to find up to 16psi and are heaps cheaper but its hard to find one rated at 20psi.

Yep they are the ones price is good as I remember our buy price out of China was around $70-80 NZD so yes well priced.

Do you have overheating issues?

[oldskool]

Yep they are the ones price is good as I remember our buy price out of China was around $70-80 NZD so yes well priced.

Do you have overheating issues?

My 14 y/o daughter rides a bigbore rmz and has a penchant to ride tight logged tracks at the sandpit. If she stops longer than a minute or two yep it starts to boil. Everywhere else she's fine. The overflow bottle I rigged up only helps so much. Over sized radiators and a higher pressure cap are on my shopping list so she can continue this urge. :brick:

[dafydd roberts]

My 14 y/o daughter rides a bigbore rmz and has a penchant to ride tight logged tracks at the sandpit. If she stops longer than a minute or two yep it starts to boil. Everywhere else she's fine. The overflow bottle I rigged up only helps so much. Over sized radiators and a higher pressure cap are on my shopping list so she can continue this urge. :brick:

I see right the rads are a good start but take it from me you need to rig a fan up of some sort it will stop it from boiling instantly there are a few home made ones on ebay if you have the $$$ try find a KTM or Honda fan kit and make it fit if Suzuki don't make an aftermarket part?

The high pressure caps are good we used to sell them but they can blow pipes off and in half.

[dafydd roberts]

http://www.ebay.com/itm/Universal-Motorcycle-Dirt-bike-Cooling-Fan-Kit-CR-F-YZ-F-KX-F-RM-Z-SX-MX-/160821442648?pt=Motorcycles_Parts_Accessories&hash=item2571b47858&vxp=mtr

[Ktmboy]

I'd go for the fan option. My Berg used to boil really easily but since the fan has been fitted I can seriously bush bash with no over heating problems.
Surely there are some after market ones out there.

[sootie]

Has anyone had any experience with these 'made in china' alloy radiators? Do they do as they claim? ie: 25-30% cooler engine temp.
From what I can see they have wider vanes which are double sided. How is their fitment and build quality? My factory coolant capacity is 1 ltr. Is it safe to say the fluid volume will increase to 1300ml with an oversized rad?

I don't understand why you would want to run an engine 25% cooler. (??) Car engines & larger bike engines have an optimum temperature at which they are designed to run all the time. The cooling system (including the fan) should provide more than enough cooling for any driving/riding condtions or you have a design problem. The thermostat is intended to continuously adjust the coolant flowrate so that engine temperature is always correctly maintained.

Are you saying that you need more cooling to meet the conditions under which you operate some engine?
(The old English cars pre-60s often suffered from this problem when operated in NZ.)
An over advanced ignition, operating in 40 deg C temps or blocked radiator fins can obviously cause heating problems too.

[Ktmboy]

I don't understand why you would want to run an engine 25% cooler. (??) Car engines & larger bike engines have an optimum temperature at which they are designed to run all the time. The cooling system (including the fan) should provide more than enough cooling for any driving/riding condtions or you have a design problem. The thermostat is intended to continuously adjust the coolant flowrate so that engine temperature is always correctly maintained.

Are you saying that you need more cooling to meet the conditions under which you operate some engine?
(The old English cars pre-60s often suffered from this problem when operated in NZ.)
An over advanced ignition, operating in 40 deg C temps or blocked radiator fins can obviously cause heating problems too.

Ahh.. because when radiator coolant is shitting itself out through the radiator cap it means that the bike is getting rather hot.

Dirt bikes don't get air flow at 1\2 walking pace nor are they fitted with fans.

[oldskool]

http://www.ebay.com/itm/Universal-Motorcycle-Dirt-bike-Cooling-Fan-Kit-CR-F-YZ-F-KX-F-RM-Z-SX-MX-/160821442648?pt=Motorcycles_Parts_Accessories&hash=item2571b47858&vxp=mtr

Hey that's interesting...DIY do-able for even me. Plenty of pix there to go by too. I could even flash up a micropic to give it some smarts and a visual display.


120mm x 120mm x 25mm (4 3/4"x 4 3/4"x 7/8") fan pulls 75cfm of cool air through your radiator powered by a 1800mAh Nickel-metal hydride (Ni-MH) battery pack. This battery will run the fan for an hour continuously. That's usually good for 4-6hrs of riding time on a hot day in technical terrain.

Is that all the fan cfm required? And such little coverage. Is this adequate to instantly drop the temp below blowing out the top?

[barty5]

I don't understand why you would want to run an engine 25% cooler. (??) Car engines & larger bike engines have an optimum temperature at which they are designed to run all the time. The cooling system (including the fan) should provide more than enough cooling for any driving/riding condtions or you have a design problem. The thermostat is intended to continuously adjust the coolant flowrate so that engine temperature is always correctly maintained.

Are you saying that you need more cooling to meet the conditions under which you operate some engine?
(The old English cars pre-60s often suffered from this problem when operated in NZ.)
An over advanced ignition, operating in 40 deg C temps or blocked radiator fins can obviously cause heating problems too.

There are no thermostats on these bikes and yet to see 40 deg c in auckland or NZ for that matter and radiator dont tend to block up riding in sand (and i know evan would be cleaning them every ride anyway)

[dafydd roberts]

Hey that's interesting...DIY do-able for even me. Plenty of pix there to go by too. I could even flash up a micropic to give it some smarts and a visual display.



Is that all the fan cfm required? And such little coverage. Is this adequate to instantly drop the temp below blowing out the top?

Yes not the best but unless you can pick up power from the bike the only option as far as a fan goes same as KTM boy said its the way to go.

All the after market fans KTM and Honda only cover a small space on the rad but this seems more than enough.

[bogan]

+1 to the fan plan, depending on the bikes electrics you might be able to hook up some pc fans just to test it. They're probably quite durable if you can squeeze em in behind the rads.

[sootie]

There are no thermostats on these bikes and yet to see 40 deg c in auckland or NZ for that matter and radiator dont tend to block up riding in sand (and i know evan would be cleaning them every ride anyway)
Hmmm - sounds a bit crude - is this a problem with all makes of bikes? Has anyone tried re-tuning & running these engines on an ethanol mix (Gull Hi Octane maybe)? I think that would keep the engine temperature down.
Agreed on the 40 deg C in NZ!

[oldskool]

Yes not the best but unless you can pick up power from the bike the only option as far as a fan goes same as KTM boy said its the way to go.

All the after market fans KTM and Honda only cover a small space on the rad but this seems more than enough.

I'll have a nosy at Tony's fan at the 2day'r ride. Excellent, this'll give me a project to work on over the next few weeks.

I could use one of these http://www.trademe.co.nz/motors/car-parts-accessories/performance/gauges/auction-524956508.htm and a thermistor or simply attach the thermistor lug to the aux bolt on the secondary radiator.

Thanks for the inspiration Daffyd! :headbang:

[oldskool]

+1 to the fan plan, depending on the bikes electrics you might be able to hook up some pc fans just to test it. They're probably quite durable if you can squeeze em in behind the rads.

They seem to fit and blow well. Being brushless I'm guessing they'll be fairly water resistant but time will tell. Haven't yet identified whether causing a partial vacuum to draw the heat out or blowing fresh air onto the cooling fins is more efficient. The way the fans are constructed it would be far easier to blow onto the radiator from behind, due to the flush fan case molding and also the protection of fan electricals by the fan itself. These fans aren't polarity reversible.
There is a fair bit of air circulating through the fins tho!!

[bogan]

I don't think the bearings will like the water/grit too much though. I would say have them draw the air through, that way they won't be fighting the airflow at low speeds.

[dafydd roberts]

They seem to fit and blow well. Being brushless I'm guessing they'll be fairly water resistant but time will tell. Haven't yet identified whether causing a partial vacuum to draw the heat out or blowing fresh air onto the cooling fins is more efficient. The way the fans are constructed it would be far easier to blow onto the radiator from behind, due to the flush fan case molding and also the protection of fan electricals by the fan itself. These fans aren't polarity reversible.
There is a fair bit of air circulating through the fins tho!!

Are these on your bike now?

[Jinxycat]

maybe you should talk to poggy about forced or induced air flow, it can affect the type of motor you use.

[barty5]

They seem to fit and blow well. Being brushless I'm guessing they'll be fairly water resistant but time will tell. Haven't yet identified whether causing a partial vacuum to draw the heat out or blowing fresh air onto the cooling fins is more efficient. The way the fans are constructed it would be far easier to blow onto the radiator from behind, due to the flush fan case molding and also the protection of fan electricals by the fan itself. These fans aren't polarity reversible.
There is a fair bit of air circulating through the fins tho!!

you will need to set the fans up so they pull the air through just as your car radiator fan dose :)

[ding322]

The main problem that you will face with PC fans is that they are NOT water tight. So the moisture and grit (as suggested above) will get into the bearings and wiring of them and kill them.

They will let you know if they don't like it with a horrible smell and some sort of smoke

I have seen these types of fans fail in mobile equipment due to corrosion caused by high moisture environments, but this would of taken a reasonable length of time.

One advantage is you just turn them around to reverse the direction of flow.

Looks like a good fit tho

[pete376403]

If your bike has a 12 volt system you could look at the fans installed on KLR650s, designed for off roadable bike so able to survive drownings and they move a good bit of air when running. About 120 mm diameter.

[oldskool]

I don't think the bearings will like the water/grit too much though. I would say have them draw the air through, that way they won't be fighting the airflow at low speeds.

Yes you're probably right about the bearings. With this in mind I'll regard the PC fans as temporary until they kark. Then I'll scour the internet for decent replacements. Shouldn't affect how I rig up the temperature sensor circuit tho. In regards to low speed turbulence caused by blowing back....I wonder if the induced turbulence may actually help dissipate the heat more effectively? ...just a random thought



dafydd roberts: Are these on your bike now?

They're just pinned there at the moment for sizing. 1x 120mm would be too large. 2 of these are 80mm.



Jinxycat: maybe you should talk to poggy about forced or induced air flow, it can affect the type of motor you use.

Pogs gave them a squiz last night but was more concerned about powering them up rather than airflow. Getting a modified stator is out of the question. A compact 12V 1.4a/h SLA were my thoughts.

[oldskool]

Bloke selling the oversized radiators on Trademe finally replied.
"hi there, you need make the fit, this radiator thicker than standard, thx."

Meanwhile I left a PC fan in a tub full of water overnight. Plucked it out this morning and sprayed it with WD40. Powered it up and it ran sweet.

[bogan]

Meanwhile I left a PC fan in a tub full of water overnight. Plucked it out this morning and sprayed it with WD40. Powered it up and it ran sweet.

Throw some river sand in the water and shake it around a bit, reckon it might not last so good then.

[L Rider]

Meanwhile I left a PC fan in a tub full of water overnight. Plucked it out this morning and sprayed it with WD40. Powered it up and it ran sweet.

I'd say it'll be like the wheel bearings on wee KTM 50's. They're not sealed/covered like on bigger bikes so they shit themselves regularly mainly due to waterblasting. Sometimes you'll get a decent amount of hours out of them other times not so many.

[oldskool]

804 grams give or take some. I'm happy with that. Tawny will be happy enough with the minimal increase in weight too if it means she can ride carefree without me being the overbearing dad!
I settled with a Jaycar Temperature sensor kit in the end. $26. Couldn't be bothered with isolating a micropic from ignition interference so I opted for a kitset instead of custom building one.
The batt is a 12V SLA from jaycar, $22. It fits in the airbox snug as a rug. I figure I clean the air filter every ride anyway so won't wire in a recharging socket to the side of the bike.
272267

[dafydd roberts]

804 grams give or take some. I'm happy with that. Tawny will be happy enough with the minimal increase in weight too if it means she can ride carefree without me being the overbearing dad!
I settled with a Jaycar Temperature sensor kit in the end. $26. Couldn't be bothered with isolating a micropic from ignition interference so I opted for a kitset instead of custom building one.
The batt is a 12V SLA from jaycar, $22. It fits in the airbox snug as a rug. I figure I clean the air filter every ride anyway so won't wire in a recharging socket to the side of the bike.
272267

Let me know how the field test goes if it still boils or not.

[oldskool]

Let me know how the field test goes if it still boils or not.
Yup will do. Field test wont be until next weekend. If it fails then I'll have to look at mounting a 120mm fan to the front of the rad.

[bsasuper]

Has anyone had any experience with these 'made in china' alloy radiators? Do they do as they claim? ie: 25-30% cooler engine temp.
From what I can see they have wider vanes which are double sided. How is their fitment and build quality? My factory coolant capacity is 1 ltr. Is it safe to say the fluid volume will increase to 1300ml with an oversized rad?

They wont have a 25-30% decrease in engine temp, they will just keep the engine temp "normal temp" for a longer period when slow riding(no air flow throught rads), the thermostat is what controls the engine temp.

[flyingcr250]

They wont have a 25-30% decrease in engine temp, they will just keep the engine temp "normal temp" for a longer period when slow riding(no air flow throught rads), the thermostat is what controls the engine temp.

MX bikes dont have a thermostat

[oldskool]

Okay just finished the final touches, ie: lacquer sprayed circuit board and fan circuits, fitted battery box and set thermistor into hollowed out bolt head. Ran it up to operating temp (hot to touch, throttle snaps responsive) and waited. Fans kicked in but don't know at what temp... I left my digital thermometer at work. I preset it to when the kettle boiled.
So it'll be a trial and error calibration for now. There's a trimmer pot to tweak for temp switching. Should be interesting. Bring it on!

[oldskool]

Now to wait for the weekend :drool:

[oldskool]

Let me know how the field test goes if it still boils or not.

Tawny rode it for 4 1/2 hours (engine hours) at the sandpit yesterday. A bit of everything. Did a few reds, some of Shane's specials, including slow unmarked hilly windy tracks. Fans kicked in every so often, especially when bike was on it's side and still running while she struggled to pick it up. They would run for a couple of minutes and switch off as the rads cooled. Didn't take much to keep them off the boil. Didn't lose any water.

Washed the bike with Dynamo last night, gave the fans a good drowning, ran a hairdryer over the sensor, fans fired into life after about 2 minutes of hot air. Battery still reading 12.56v (started at 12.75v)

Next test will be in wet clay. I've already sourced some IP68 rated fans so if these normal ones fail then the totally sealed IP68's will be the next step.

But for now I'd say the project so far has been successful!

[dafydd roberts]

Tawny rode it for 4 1/2 hours (engine hours) at the sandpit yesterday. A bit of everything. Did a few reds, some of Shane's specials, including slow unmarked hilly windy tracks. Fans kicked in every so often, especially when bike was on it's side and still running while she struggled to pick it up. They would run for a couple of minutes and switch off as the rads cooled. Didn't take much to keep them off the boil. Didn't lose any water.

Washed the bike with Dynamo last night, gave the fans a good drowning, ran a hairdryer over the sensor, fans fired into life after about 2 minutes of hot air. Battery still reading 12.56v (started at 12.75v)

Next test will be in wet clay. I've already sourced some IP68 rated fans so if these normal ones fail then the totally sealed IP68's will be the next step.

But for now I'd say the project so far has been successful!

Would they be these? http://www.youtube.com/watch?v=AbQILgx5KU8

[cheese]

You could probably add a LED to indicate close to boiling point too so you know you need to turn the bike off. Or a temp gauge?

[oldskool]

You could probably add a LED to indicate close to boiling point too so you know you need to turn the bike off. Or a temp gauge?

You mean something like this?
274391

[scumdog]

An over advanced ignition, operating in 40 deg C temps or blocked radiator fins can obviously cause heating problems too.

An engine without enough advance (i.e. retarded) causes overheating.