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Macstar
16th July 2006, 16:20
Having just bought this bike 10 days ago second hand I am having overheating problems. Low on cash and a student, I'm hoping to replace things myself... Maybe some of you gurus can offer some advice on what could be the cause? (please) Here are the symptoms:

First of all, the bike is fine when moving but in traffic it overheats and last night it actually shut down the engine (I guess there's a fail safe). Obvioulsy i wouldn't have kept going if I knew it was that hot as according to the temperature guage at the time it was in the middle and no where near the red zone. So I guess my temp guage is faulty?

Next: I read on-line that if you can see coolant leaking from the pump the seals are probably gone. Well there is some leakage but do I really need to replace the whole pump or just the seals?

It has lost no fluid (apart from minor spots out of the water pump), so I don't think there are any leaks elsewhere that could be causing the overheating.

Should I go for a new thermostat, radiator flush and pump seals and see if that works? Would that make the temperature guage operate correctly? Cause I guess the radiator cooling fans aren't going to switch on until it gets to at least half way on my faulty temperature guage right, which could be adding to the problem.

One other crazy thing happened: The engine shut down (turned off) as mentioned last night when it presumably overheated and I left the ignition on with the radiator cooling fans doing their thing. I put the bike on its stand and suddenly after about 4 minutes the engine re-started automotically. Unfortunately my bike was in gear though and it went flying off with no rider at the helm. My immaculate body work is now scratched and the gear shifter snapped off. Gutted! Has anyone ever heard of a bike automatically starting again - seems pretty crazy! True story though.

98tls
16th July 2006, 16:32
:gob: never heard of a bike self starting....whats the oil like ie any water in it..thinking head gasket but not sure.also wondering of the consequences of a thermostat not opening.

MacD
16th July 2006, 17:54
Well that sounds all very strange (unbelievable really)! The RFs generally run cold due to a low temperature thermostat (opens at 78 degrees C), which is about 1/3 of the way up on the temperature guage. Sitting in traffic my bike will heat up though and the fan comes on at around 2/3 reading on the guage.

I don't know of any thermal cutout or similar so I would suspect that you may have some other electrical problem which caused the engine to stop, and maybe also was responsible for the very odd restart?

Check the wiring loom where it runs through the frame on the right-hand side just behind the steering head. The loom can wear through here as it moves as you turn the bars. I've added extra tape around the loom to protect mine, maybe you have a short at this point?

If you start the bike with the coolant cap off you should be able to see the flow of coolant. The thermostat has about 5 drill holes in it so even a closed/stuck thermostat should let quite a reasonable flow past.

Anyhow, I'd check the electrics as much as the cooling system given the symptoms. Good luck!

Macstar
16th July 2006, 18:05
Yeah I was too scared to check for water in the oil incase you're right about the head gasket. It hasn't lost any fluid so I'm hoping that's sweet, but will check that tomorrow (bike was towed to a mate's place). The electrics could be a problem too I'll have a looksee there too thanks. I'm hoping that's not the case I know how fidgety and subsequently expensive electrical stuff can be. Thanks guys.

JimO
16th July 2006, 18:09
if the stand was down it should have stalled

Macstar
16th July 2006, 18:18
True! I know that feature does usually work on my bike. At the time it self started I had a steel u-lock passing through the rear disc rotor. When it took off on its own last night it actually broke the lock! I think if it weren't for that lock though the bike could have gone flying into some parked cars! The Rf's must have a fair amount of torque to smash a lock and take off on a bunny hop start...

MacD
16th July 2006, 18:20
Here's a live link (http://www.diff.ru:8000/Suzuki_RF900(R-RS-RT-RV)_'94-97_Service_Manual.zip)to a copy of the RF900 service manual (http://www.diff.ru:8000/Suzuki_RF900(R-RS-RT-RV)_'94-97_Service_Manual.zip).

DingDong
16th July 2006, 18:30
The bike wont start without the clutch engaged and the stand up... you would have to have an elc fault in both these and the starter switch or starter motor as well, seems highly unlikely and this all sounds like bull-shit to me, come-on own up... it pissed you off and you threw it to the ground didnt ya.

If the bike is overheating, the coolant will come out the overflow... unless the pump is stuffed or the T/stats jammed restricting flow.

If it overheated to the point it cut out, sorry dude your bike is gonna cost ya plenty... I'm not aware of any failsafe on the RF engine

DingDong
16th July 2006, 18:36
True! I know that feature does usually work on my bike. At the time it self started I had a steel u-lock passing through the rear disc rotor. When it took off on its own last night it actually broke the lock! I think if it weren't for that lock though the bike could have gone flying into some parked cars! The Rf's must have a fair amount of torque to smash a lock and take off on a bunny hop start...

Now, you've done it!, the rotor would have broken before the U bolt:nono:
I dont believe this is a real post...

Macstar
16th July 2006, 18:45
Come on guys - I've got no reason to bull shit. I'm seriously devastated. I sold my prized SRX400 to get this bike and saved for over a year. Now this has happened and I'm out of cash and with no transportation at all (apart from the bus). I swear every detail is 100% as it happened. The ubolt lock was a $25 shitty one, not a proper disc lock one and so yeah it broke before the disc rotor. I've just signed up to this site so I don't know if people usually lie here when they post stuff, but that's not what I'm about. Anyway what good would it do me in terms of finding out what is wrong with my bike if I distorted the details??????? The bike started on its own with the keys in the ignition and the stand down. This was about 4 minutes after the engine stopped on its own. I left the key turned on so that the radiator cooling fan would keep going whilst the engine had stopped cause I thought it obviously needed it (like some European cars do after you turn off the engine and walk away, the fans keep going for a minute or two). It jumped about 1 metre and fell on its side. I was standing next to it and pulled the clutch in (BUT BY THIS STAGE THE STAND HAD FLICKED BACK UP CAUSE IT HAD MOVED FORWARD). I managed to lift the bike back up on my own and no the engine was not still going at this stage.

DingDong
16th July 2006, 18:52
Come on guys - I've got no reason to bull shit...

People dont usually b/s... but your story is just so unbelievable, OK I'll give the bene of the doubt.:yes:
But you must be the unluckest biker still breathing:doobey:

imdying
16th July 2006, 19:30
First of all, the bike is fine when moving but in traffic it overheats and last night it actually shut down the engine (I guess there's a fail safe). Obvioulsy i wouldn't have kept going if I knew it was that hot as according to the temperature guage at the time it was in the middle and no where near the red zone. So I guess my temp guage is faulty?

Next: I read on-line that if you can see coolant leaking from the pump the seals are probably gone. Well there is some leakage but do I really need to replace the whole pump or just the seals?

It has lost no fluid (apart from minor spots out of the water pump), so I don't think there are any leaks elsewhere that could be causing the overheating.

Should I go for a new thermostat, radiator flush and pump seals and see if that works? Would that make the temperature guage operate correctly? Cause I guess the radiator cooling fans aren't going to switch on until it gets to at least half way on my faulty temperature guage right, which could be adding to the problem.They're just playing with ya mate.

First things first, cooling system. What makes you think that it's overheating if the gauge is reading ok? Is it steaming/boiling or something quite obvious?

Nothing other than a wiring fault, or faulty temp sender would make the gauge read wrong. The fans probably turn on using the same sender as the gauge, it that sender is rooted, neither the fans nor the gauge will operate properly. Test that sender. Probably a procedure for it in an RF900 manual, but you can always dangle it in a pot of boiling water and see what the gauge reads (just jerry rig some longer wires..). You indicate that your fans do work (left the key on so they'd work), which indicates either the sender is ok, or the fans and gauge have seperate ones, you'll have to establish that for yourself as I have no idea on your model.

Where abouts is the leak on the waterpump? If your pump is knackered, that would account somewhat for any overheating. Find out what a new pump is worth. Perhaps Motu can shed some light on how much leakage is a problem (I'm assuming it's coming from the small hole at the base of the pump?). I'm guessing any leakage is indicative of a worn pump, and should probably be replaced ASAP?

Hope that gets you started, sorting the temp problem is probably a good start.

FROSTY
16th July 2006, 19:48
That bike must have been accident damaged before methinks.
The only way this could happen is a short in the wiring loom

Sensei
16th July 2006, 19:50
Take it back to where you got it from & get Ya Money back !

crazybigal
18th July 2006, 15:18
dude you fell off! it happens.
i had a short in my wiring on my rf, the wires are quite thin and the outer casing is not that thick so it wore a hole and shorted. take the inner plastics off and trace the loom from the kill switch and the loom from the headlight back to the frame, check for a crimp or a worn patch.
as for starting on the stand with the clutch out never going to happen, you batt would have gone flat to start with as your headlight would have been on if you had left the ingnition on.



Having just bought this bike 10 days ago second hand I am having overheating problems. Low on cash and a student, I'm hoping to replace things myself... Maybe some of you gurus can offer some advice on what could be the cause? (please) Here are the symptoms:

First of all, the bike is fine when moving but in traffic it overheats and last night it actually shut down the engine (I guess there's a fail safe). Obvioulsy i wouldn't have kept going if I knew it was that hot as according to the temperature guage at the time it was in the middle and no where near the red zone. So I guess my temp guage is faulty?

Next: I read on-line that if you can see coolant leaking from the pump the seals are probably gone. Well there is some leakage but do I really need to replace the whole pump or just the seals?

It has lost no fluid (apart from minor spots out of the water pump), so I don't think there are any leaks elsewhere that could be causing the overheating.

Should I go for a new thermostat, radiator flush and pump seals and see if that works? Would that make the temperature guage operate correctly? Cause I guess the radiator cooling fans aren't going to switch on until it gets to at least half way on my faulty temperature guage right, which could be adding to the problem.

One other crazy thing happened: The engine shut down (turned off) as mentioned last night when it presumably overheated and I left the ignition on with the radiator cooling fans doing their thing. I put the bike on its stand and suddenly after about 4 minutes the engine re-started automotically. Unfortunately my bike was in gear though and it went flying off with no rider at the helm. My immaculate body work is now scratched and the gear shifter snapped off. Gutted! Has anyone ever heard of a bike automatically starting again - seems pretty crazy! True story though.

ManDownUnder
18th July 2006, 15:25
The RF will normally run at quite a cool temp - the temp gauge indicating only one or two lines above the bottom of the gauge.

If it's actually too hot it could be a lack of coolant (coolant tank is under the seat, mounted on the left hand side and you might (MIGHT) be able to see the coolant level through the tine wee window they built into the fairing.

It also might be the thermostat (located inside RHS of full fairing).

The enging dying I can't comment on but restarting??? That means the starter solenoid would have to be livene in order to spin the engine up... which sounds very VERY strange to me.

I hear Atomic are currently wrecking an RF too - I want some bits off it, and you might get some of the stuff you seek too... dunno what prices they have in mind though.

Colapop
18th July 2006, 15:51
I'd have to agree with all that's been said so far. This is not an issue you want to be f*cking around with yourself unless you are a bike mechanic who knows bikes inside out (if that were the case you wouldn't be asking here). Sounds like an electrical fault - RF's are usually fairly bullet-proof. You can one of two things;
a) take back to where/who you bought it from and either get your money back or get it fixed.
b) take it to a good bike mechanic and get it fixed properly - yes it will cost but an RF will go for a hell of a long time so you should get your money's worth of riding out of it.

Macstar
18th July 2006, 19:48
Seems my problem has got a few people scatching their heads, obviously including me. There's been some really useful suggestions and advice and I think they guy who questioned whether the temperature guage was even playing up in the first place might have been on a roll. Then there's some people who still would prefer to think bikes can't go haywire and do weird things. Especially that last guy who reckons a battery would go flat from leaving the headlight on for 4 minutes... Anyway, I wanted you all to know that I've handed the RF over to a professional bike electrician / mechanic and I am hoping to hear back from him in the next day or two with his take on what caused it. I'll be sure to post his findings up here when I know cause I am sure some of you will be curious to know how such a bizarre occurance could come about. According to him it is most probably the wiring loom in around the steering i.e. when the handlebar was turned fully to the left to park, it would have stretched the cables and IF there was a worn cable outer etc it could have shorted then. Anyway... stay posted and thanks!

Macstar
18th July 2006, 19:52
Thanks, I'll mention that starter solinoid to the mechanic / electrician.

Colapop
18th July 2006, 19:52
Good thinking that man! Far better to get sorted profssionally especially if you're not quite sure.

The recpetion you've recieved could probably have been better but with such exceptionally bizarre circumstances ... I'm sure you'll understand. Get out on a few KB rides and you'll find a great bunch of people. The knowledge on here is pretty good - except when someone comes up with something that just bizarre!
Welcome.

Macstar
19th July 2006, 09:14
Cheers again. What's the KB? Is that a club? Im defn keen to meet a few others and absorb some of their knowledge & hear biker tales etc. Which club can you recommend for road trips but not so much racing?

ManDownUnder
19th July 2006, 09:20
Cheers again. What's the KB? Is that a club? Im defn keen to meet a few others and absorb some of their knowledge & hear biker tales etc. Which club can you recommend for road trips but not so much racing?
See my PM to you

terbang
19th July 2006, 09:40
Wow thats an odd one, hope you get it sorted. I've seen small magneto engines self start but something as complex as a 4 cyl bike engine is really odd. Hope your mechanic is a good one and good luck. The KB is just this internet type thing we are all part of here and we have some great rides. See ya there..

emaN
19th July 2006, 10:03
Just seen yer thread dude..
looks like you're getting it sorted.
(will check my loom sometime soon & do the 'tape thing' MacD suggests)

Hope this don't put you off RF's; they're great strong bikes.
(just need a tail mod & they're sweet!)

Welcome!

Lou Girardin
19th July 2006, 10:41
Has the bike got an alarm with remote start fitted? Look for a black box roughly the size of a packet of smokes under the tailpiece or sidecovers.
If these are wired incorrectly they can start in gear. A fault in the immobiliser can cause the stalling too.

Macstar
24th July 2006, 20:14
Hey guys

Finally some answers on the bizarre problems my RF was experiencing. Firstly I'd like to thanks "Lou Girardin", Mac D, "Imdying" and "Man Down Under". These guys were aboslutely awesome in their comments and really showed their wisdom with each member identifying one or more of the actual causes of the problem. If you guys aren't already bike mechanics / electricians YOU SHOULD BE!

Someone in the past had modified the wiring. My repair guy reckons probably there once was an alarm fitted. Apparently where some of the loom had been cut, the newly added replacement wires were not thick enough to handle the load. It was a ticking time bomb and eventually the wires heated up and shorted. This f*&%cked the starter motor solenoid and made it bascially live 24/7 i.e. you didn't even need to have the key in the ignition for the starter motor to go (if and when it wanted to). Apparently it was pretty messy in there and aside from replacing the starter solenoid, all the wiring in that neck of the woods has had to be checked etc. The repair guy is bloody awesome though and has hooked me up with a wicked student discount of around $200 in total. I didn't dare ask how long it took him so as not to jeapordize his generous price...

Apparently the bike never overheated (Sorry for misleading everyone) though some people mentioned-above did question this assumption! But in any case I'm going to give it a radiator flush anyway.

I've ordered a new gear shifter (Taiwanese one) for $55 vs Suzuki standard @ $130 and apart from some scratches and damage to the paint work I hope to back on the road by Wednesday! YEAHHHHHH!

So all up about a $300 run-in (forgetting about cosmetic damage), which I am extremely thankful for and hopefully upholds the RF900 as a reliable bike!
Next is a new rear tyre, chain and sprocket. I'll save up a while for these...

Thanks again guys - really appreciated.:scooter:

riffer
24th July 2006, 20:42
Phew!

Just caught this thread tonight and you had me scratching my head too.

I'm glad you got it sorted. The Rf's are a great reliable bike and hopefully you won't have any problems from now on.

Welcome to Kiwibiker. Good to see another RF rider here.

Drum
24th July 2006, 20:56
Good to hear you got your problem sorted.

I hope we all learned a lesson here. Just because we dont understand something doesnt mean it didnt happen!

The Pastor
24th July 2006, 20:58
That would have freaked me out man, a bike starting all by itself!

imdying
25th July 2006, 17:40
Make sure you take him a 1125 of Jimmy. Good trademan are bloody hard to find in this country, and it'll be quite possibly worth every penny to show your appreciation in this way :yes: