Having trouble keeping coolant in the bike at times

[joetroop30]

I have an 02 S that I have stripped down to make it a better dirt bike.  No thermostat, turkey baster mod, radiator guards.  When I ride singletrack trails and have to keep it in 1st and 2nd gear for prolonged periods of time the bike will almost always overheat and shoot coolant out on the trail.  I know someone will say it so I'll beat them to the punch, "Why don't you ride faster so you get better airflow/cooling?"  The answer is because on the trails I'm riding it's all but impossible for me to get out of 1st or 2nd gear and get more speed going. 

 

Is there anyway to get better cooling with different aftermarket radiators?  My stock radiators are fine, not folded or bent.  Radiator cap has been tested, it's fine.  I have aftermarket silicone radiator hoses.  Fan was removed a long time ago, and been thrown away.  Maybe I should try different coolant?  I've had this happen with several different coolants that I've run.  Never run Engine Ice, maybe I should give that a try?  Maybe a higher pressure cap?  

 

Most of the time that this is happening I'm riding in the Moab/Swell  area and it's in the 80's or 90's.  The guys I'm riding with are on different bikes (CRF450R and WR450), riding the same speed and not having this issue.  I know those bikes are more dirt oriented and lighter than the DRZ is, but are also liquid cooled.  Been thinking about getting a different, lighter, more trail oriented bike, but I love my DRZ and want to keep riding it on trails until it has a mechanical failure that isn't worth fixing.        

[thedigitel]

Fan was removed a long time ago, and been thrown away.  

 

 

Sounds to me like this might be your problem, and an easy solution.  The radiators are probably getting less airflow with the guards installed, making the problem worse without a fan.

Edited May 8, 2014 by thedigitel

[joetroop30]

Most other dirt bikes don't have fans.  My understanding is that the fan was more or less for people who used it as a commuter bike and were stuck in traffic, not moving, for periods of time.  The fan is just extra weight in my opinion, and isn't needed for trail riding. 

[bmwpowere36m3]

I have a '00 S model and I also ride some tight, 1-2nd gear, stuff here in the NE.  The cooling system is stock (radiators, thermostat, fan, expansion tank), besides silicon hoses and radiator guards.  I run a 50/50 mix of Zerex G-05 and I've never had the bike overheat or spew coolant… at least I’ve never seen it spew and I haven’t lost any fluid.  Removing a thermostat isn’t always a good idea because it restricts flow to a degree and allows time for coolant to absorb and expel heat.

 

Does the coolant temp idiot/warning light come on (red thermometer) when it overheats?  Maybe your cap is not holding pressure fully.

[bmwpowere36m3]

Most other dirt bikes don't have fans.  My understanding is that the fan was more or less for people who used it as a commuter bike and were stuck in traffic, not moving, for periods of time.  The fan is just extra weight in my opinion, and isn't needed for trail riding. 

 

Exactly!  Much like a car stuck in traffic with the A/C on, a bike running in 1-2nd gear under high-load isn’t getting much airflow… fans definitely help.

[joetroop30]

I removed the stock display(speedo, indicator lights, etc)  several years back, so no more overheat light at all.    All associated wiring for it was removed as well.  So maybe putting thermostat back in wouldn't hurt.   

Edited May 8, 2014 by joetroop30

[BillDirt1]

I have an 02 S that I have stripped down to make it a better dirt bike.  No thermostat, turkey baster mod, radiator guards.  When I ride singletrack trails and have to keep it in 1st and 2nd gear for prolonged periods of time the bike will almost always overheat and shoot coolant out on the trail.  I know someone will say it so I'll beat them to the punch, "Why don't you ride faster so you get better airflow/cooling?"  The answer is because on the trails I'm riding it's all but impossible for me to get out of 1st or 2nd gear and get more speed going. 

 

Is there anyway to get better cooling with different aftermarket radiators?  My stock radiators are fine, not folded or bent.  Radiator cap has been tested, it's fine.  I have aftermarket silicone radiator hoses.  Fan was removed a long time ago, and been thrown away.  Maybe I should try different coolant?  I've had this happen with several different coolants that I've run.  Never run Engine Ice, maybe I should give that a try?  Maybe a higher pressure cap?  

 

Most of the time that this is happening I'm riding in the Moab/Swell  area and it's in the 80's or 90's.  The guys I'm riding with are on different bikes (CRF450R and WR450), riding the same speed and not having this issue.  I know those bikes are more dirt oriented and lighter than the DRZ is, but are also liquid cooled.  Been thinking about getting a different, lighter, more trail oriented bike, but I love my DRZ and want to keep riding it on trails until it has a mechanical failure that isn't worth fixing.        

 

+ 1 on the Enging Ice.

[Signman606]

+ 1 on the Enging Ice.

 

I use engine ice too, never hardly had my fan come on. There's 2 kinds, one has a antifreeze mix to it, and the other one, not. The greenish/turquoise one has the antifreeze mix which I need for our temps here in the high desert. Actually, most guys who have bikes that I know use it........

[BillDirt1]

I use engine ice too, never hardly had my fan come on. There's 2 kinds, one has a antifreeze mix to it, and the other one, not. The greenish/turquoise one has the antifreeze mix which I need for our temps here in the high desert. Actually, most guys who have bikes that I know use it........

 

Thanks for that info, I didn't know that.  

[hinksy]

A lot of people are now using computer fans . You can wire it up through a toggle switch and everytime you hit the tight stuff , you can switch it on . Then when you get back out in the open you wont need it so you can turn it off , greg

[fuentes52]

I removed the stock display(speedo, indicator lights, etc)  several years back, so no more overheat light at all.    All associated wiring for it was removed as well.  So maybe putting thermostat back in wouldn't hurt.   

?

[707drz]

i think you need to find some donor parts and re think your approach on the cooling system. if you are worried about weight consider reinstalling parts and substitute oem fan with a thin light weight computer fan.

[joetroop30]

?

I'm the one who took all that crap off the bike and I'm glad I did.  It will never be put back on and almost all of it was sold on e-bay.  I use my bike pretty much exclusively as a dirt/trail bike.  All I need is my bar mounted GPS-it tells me everything I need to know. 

 

i think you need to find some donor parts and re think your approach on the cooling system. if you are worried about weight consider reinstalling parts and substitute oem fan with a thin light weight computer fan.

As I stated above I don't need a parts donor because those parts ain't ever going back on.  The fan idea isn't a bad one and is one I will definitely look in to.  Worst case scenario is that I just have to keep replacing coolant after riding the nasty singletrack. 

[TB4ME]

My 2002 400s did just what yours did when in tight trails with no fan. Would boil away half it's coolant in 20 minutes.  I had to put computer fan on or forget riding in dirt.  Also, get rid of that goofy turkey baster and put the stock overflow tank back on. It can hold 4 times the coolant and won't blow it out  on ground when really hot.

[SteveROntario]

Why not put the fan back on like it is supposed to be?  I've had the gas boiling in my tank without overheating the engine.

Steve

[rraiderr]

I used to pull the fans off my track bikes.

 

In the end it was not worth it, the little weight is saved was not as valuable as the air flow it provided.

[joetroop30]

Yeah I think putting the fan or a fan back on it will go a long way to helping me out.  Also gonna give Engine Ice a shot.  Thanks for the help.

[wingam00]

You bike maybe jetted wrong and running on the lean side which would make it run hotter.

[Beta300REcat]

................ and allows time for coolant to absorb and expel heat.

 

 

 

Nonsense.  More flow = more heat removal.

 

 

I run a 30% coolant mix and WaterWetter, but I also still have my fan. I know when the fan finally does kick on, she's getting pretty warm!

[Craigo]

It just seems way too obvious to this black duck........ ?

 

If you got issues with heat, Re install the stock fan with a manual over ride switch.....