How far can it be ridden, and how can I tell if its overheating

[Cobalt]

Hi Folks I know this is going to seam a really dumb question so here goes I have been told that my GN 250 been a commuter bike its not supposed to be ridden to long as it will over heat and it will sag the engine. My question is how far can it be ridden and how can I tell if its over heating ? Would heavier oil stop it over heating letting me ride further? :spudwave:

[Edbear]

If you're GN is in reasonble nick, just use the recommended iol and change it according to the specs. You should be able to hop on it tomorrow and ride straight to Bluff. You might not last the trip, but the GN certainly will!

[Edbear]

Just checked and saw you're in CHch! The GN would happily cruise to the big Auck if you were of a mind too!

[Cobalt]

My Gn Has only 1653 k on it its still shiny and new I was going to ride down to Dunedin but the guy at the shop said it was to much for a GN in one go

[diggydog]

i've had this problem going back a few years and must say when i rode my honda cl 175 back in the 70's it just stopped, i waited 5 minutes and set of again no problem. i was riding from wellington to the mount, which is a fair way, but the funny thing going back to welly it never over heated, i would say it may have been cooler that day, but as far as your gn250 it should cope no worry's, i would of thought giving ita long ride every now then would do it good.:rockon: :done:

[Ixion]

Any limitation will be because of rider not machine. I would with complete confidence set out to ride a GN250 right round NZ.

Provided you are willing to accept a "cruising" speed (say 90 to 100kph) , without holding the throttle hard to the stop the whole way, the only limit will be that you may get quite tired. But if you limit your distance to, say, 300km , you should have no troubles.

An aircooled engine will almost never overheat on the open road, if they overheat it will be in thick slow moving traffic where there is no air flow to cool the motor.

Ride the bike and do not worry about ignorant doomsayers.

[onearmedbandit]

+1 what Ixion says. (except the part about riding a GN250 right round NZ)

[Warr]

My daughter rode her '05 GN250 from Wellington to Hams to Wellington in a weekend. They are quite capable of it at the speed limit. But I do recall the dude in the bike shop giving her the long trip warning.

[Cobalt]

Thanks for the replys folks I'll take it easy and give it a rest after every 100k just incase and its a chance to have a smoke they burn down to quick unless you stop

[Lee Rusty]

I rode my old GN around NZ on a Southern Cross Road Rally 6300km in 8 days
if your arse can stand it the bike will - and cheap as well

[Racey Rider]

Could we get a better explanation of what is meant by 'SAG THE ENGINE'?:spudwhat:
Never heard of it!

Sounds like the type of thing some would say to try and sell ya a bigger bike.

The GN would make a NZ tour. Not the perfect bike for it, but a well mantained one would make it here there and back again, no matter where in NZ the 'Here / There' was.

[Fub@r]

I did a 300km round trip on mine the other week, never missed a beat and that was on one tank of gas :scooter: Did have a sore butt afterwards but it was fun

I have been warned also about long trips on a Ginny but I heard it was that the wheel bearings cant handle it?

Only thing I would keep a check on is your oil levels

Also for a long trip keep it to 90-100 (not that you have much choice) but don't ring it out too much

[Jantar]

I would stronly suggest that on a long trip on a GN250 that you stop every 200 - 240 kms for 5 minutes or so. If you push too much past that then the engine will stop. It will not restart again untill you add fuel to the tank. So its a good idea that when you make that stop that you fill up and check the oil at the same time. As long as you do that then, as Lee Rusty says, you can ride right around NZ.

[Cobalt]

Thanks for the Help Guys

[Steam]

Weird that they said a Gn wouldn't make it.
My GN is 20 years old, a 1986 model, and I rode it from Auckland to Wellington in a weekend, throttle to the stop all the way. I kept it topped up with oil, ran it on 91, and the engine got hot but not too hot to touch. Too hot to keep your hand on it, but not as hot as a boiling steel kettle or something like that.

The main threat is running out of oil. If it runs out of oil, bits of metal will overheat and expand, while other bits of metal will stay the same size, and it will seize. Check those oil levels every time you fill it up with petrol.

[marty]

considering a trip of this nature would only be 2 tanks of gas, is he saying that the bike won't survive 2 tanks of gas?

[DingDong]

What everyone has been saying... its just an engine, It'll ride where ever you want it to for as long as you have gas in the tank and oil in the pan... dont put thickr oil in it... it will break.

But say'n that I've never owned a GN, but I have had DR's which are basicly the same engine... thrash it!

[hobdar]

Yup brought mine in Tauranga 2005 and drove it back to Wgtn in one night...no problems cept the missus in the car had my wallet, we got seperated and she never thought to stop and wait for me......no cellphone sigh it was a long night....and had some very friendly people pay a couple of times for my gas....

Still runs sweet but it now looks crusty...after a year and a half.......motor is loosing its chrome and other metal parts are rusting..sigh..:crybaby:

[sunhuntin]

My Gn Has only 1653 k on it its still shiny and new I was going to ride down to Dunedin but the guy at the shop said it was to much for a GN in one go


i rode from wanganui to paeroa [about 6 hours give or take.] unfortunatly, i ran into the "round the lake run" around lake taupo. traffic was a dead stop from turangi to taupo. i was in full leathers and figured if i was overheating, so was the bike. i ended up splitting when i could.
i stopped every few towns to double check my map, but have no doubt i could have made it in one run, no stops. two days later, i rode from paeroa to rotorua and the following day, rotorua to home. those last two were non-stop, except for petrol and lunch.
just make sure you check the oil before you go, fill if needed and might pay to let the engine cool fully and check again before the return trip. mine hasnt taken any oil since the last service, nearly 5000k ago.

i was told not the check the oil unless the engine was entirely cold, cos if its hot, its still amongst the parts in the engine...hasnt run down. i checked mine the next morning. didnt need any though. same rules apply for cars...you dont get a clear reading.

word of warning...learn the rev to speed ratio [ie, 6000rpm = 100k] cos mine killed my speedo coming home, so had no idea how fast i was going, nor how many k's id done between petrol stops.

[twinkle]

I've ridden my gn for maybe half a dozen 8 hour rides and many more 5ish hour rides. It still goes fine. I'm just hoping the bike doesn't rust away before I wear the engine out.

[ManDownUnder]

Cobalt,

The GN has an engine that's a very well established and rock solid design. There are a lot of them around, simply because they go... and go... and go.

As someone said - the bike will outlast you on a single journey... easily!

[Grantasaurus]

I agree that you should be able to open road a GN as long as you want. Just make sure it has fresh oil before you do anything like 6600 k's in 8 days!
How did the chain cope with that?
Like ixion said, the only thing that'll make it overheat is slow traffic.
No airflow on an air-cooled engine = no cooling

[sunhuntin]

I agree that you should be able to open road a GN as long as you want. Just make sure it has fresh oil before you do anything like 6600 k's in 8 days!
How did the chain cope with that?
Like ixion said, the only thing that'll make it overheat is slow traffic.
No airflow on an air-cooled engine = no cooling

ooo good point grant!! my chain has needed replacing twice after long rides [wanganui to paeroa/wellington] but has been fine since last replacement.

[Motu]

, the only thing that'll make it overheat is slow traffic.
No airflow on an air-cooled engine = no cooling

The same with a water cooled engine (indirectly air cooled),no airflow and they will overheat - it's the fan that provides the airflow.

My watercooled bike has no fan,and never overheats,it has been designed for low speed use.An yes,there are aircooled bikes with fans...scooters,and they don't overheat in traffic.

[Grantasaurus]

Yeah, but a water cooled bike will always take much longer to reach the same point, and so they're more resistant to it.
The specific heat of water is much higher than any metal or oil, ie it takes a lot more heat to increase its temperature by say 1 degree.

[Motu]

The watercooled bike will boil the coolant....the aircooled bike will just keep going.....

[Grantasaurus]

... Until it completely breaks the oil down and the motor seizes, yeah. Both will do it, although the water cooled motor will always take longer.
My point is, even without a fan a water cooled motor will always take a lot longer to kill its oil, because of the fact that it has the radiator water in addition to the metal fins etc on the motor to absorb and radiate heat.
They are more tolerant of it, if you like.

[BAD DAD]

Years ago we rode a CB100 two-up all the way from Auckland to Bay of Islands. The bike handled it perfectly OK because we didn't thrash it and like some of the other crew are suggesting, it's your backside that will let you know when it's time for a rest. Open road riding has got to be easier on a aircooled engine than commuting. By the way, thats a nice road between CH & Dunedin eh.

[Ixion]

... Until it completely breaks the oil down and the motor seizes, yeah. Both will do it, although the water cooled motor will always take longer.
My point is, even without a fan a water cooled motor will always take a lot longer to kill its oil, because of the fact that it has the radiator water in addition to the metal fins etc on the motor to absorb and radiate heat.
They are more tolerant of it, if you like.

Well before the water cooled motor gets oil hot enough to be a problem (with modern oils), the engine will have suffered major damage in other ways.

Once the temperature of a water cooled engine reaches boiling point (about 110 degree C or so usually), the coolant will, surprise, boil. This causes steam to be generated. Steam in an engine is BAD news. Continue for long with the water boiling and you will blow headgaskets, water will leak into the oil and emulsify, steam pockets will prevent circulation and cause local hot spots and detonation, the water pump will cavitate , causing all sorts of horrible things to happen.

The air cooled engine will go happily on. I've seen air cooled engines running happily with the exhaust headers glowing red.

Eventually, I guess it would be possible to get an aircooled engine hot enough that the oil broke down causing seizure. But on a four stroke, with modern oils, I doubt you'd ever see it off the race track. Generally before that point either the carbs will get so hot the motor will run like shit, or an exhaust valve will stick in the guide (which may also be a BAD thing).

Even aircooled two strokes, where cooling is much more demanding, and lubrication on the edge of non existent, will run at very high temperatures without problem.

The advantage of water cooling is not that it offers greater protection to the engine , but that it offers the ability to remove the cooling surface away from the engine. On a large powerful engine, even a single cylinder, it gets hard to accomodate big enough fins. On a multi, very hard indeed. How do you provide sufficient "finnage" for the middle pots?

Really the only reason the water exists is to enable the heat to be transported somewhere away from the cylinder head, to a place where there is more room for cooling surface.

[McJim]

I'm a smug bastard then coz my wee 250 is liquid cooled and has a fan behind the radiator.:)unfortunately a bike with this set up cost me twice the price of a Ginny.:(