Shutting down in the heat.

[dashp]

WTH , summer is soon approaching here in the Middle East and now that the temp get to 30deg C my bike is rough and shutting down again.
Over last year or so I changed crank sensor, coils, air intake sensor,fuel pump and hoses and today the O2 sensor to no avail!
She ran fine in the cool months and never gave a problem on long or short rides but I'm now back to square one.
Of course regular oil, filter(air&oil & fuel)changes were done.
I do all the maintainence myself and am follow the intervals as required. Total km is 50,000 and I've had her for 4 years now.
The last time it was the crank sensor but that time it just stopped running completly until i changed it , now the problem is only when daytime temps are up to 30deg plus.
Should I change the crank sensor again? A bit strange fo such a proven design!ie to be changed every 2years or so.
Thanks for any suggestions.

[kirby]

You didn't say..single plug or dual? For the single plug could be the coil is breaking down? due to heat. If dual could be the sticks (doubtful). Prob can rule out fuel as FI not prone to vapor problems.?
I know you posted under "rockster" just say'in.
Don't ya love a mystery. Where in the ME?
mike
BTW That hall sensor lives in a very inhospitable place and I have seen the wiring break down or a connector could be loose or effected by heat?? Also the handle bar switch.

[riceburner]

If dual could be the sticks ([s]doubtful[/s] HIGHLY LIKELY!).

Stick coils are designed for water-cooled vehicles where their environmental temperature (ie the temps they are exposed to) are limited to a pretty fixed range. On an air-cooled vehicle they're subjected to a much broader range of temperatures and they will break down more easily.

[kirby]

If dual could be the sticks ([s]doubtful[/s] HIGHLY LIKELY!).

Stick coils are designed for water-cooled vehicles where their environmental temperature (ie the temps they are exposed to) are limited to a pretty fixed range. On an air-cooled vehicle they're subjected to a much broader range of temperatures and they will break down more easily.

dashp You say you have replaced your sticks right? Well although it is possible that they have given up (only takes one),I ride in allot of heat in the CA deserts including death valley and in 130K miles I have never had a stick fail. That does not mean that they won't but there is no evidence at all that the stick coils in the R bikes do not meet design specification for aircooled applications. The 1200's have 4 and it makes no sense to put a part on the bike that is not up to specification for the designed range of operations. In very extreme situations I am sure its possible to exceed the designs parameters and you may have done just that. I doubt that as I have been in the same heat as you and had no trouble. To say that the coils were designed just for liquid cooled applications is not based on fact, just rumor.

Sounds like heat related ,but could be a connector,like the one from the hall sensor to the ecu .You have changed the sensor before so you know where that one is. Does the engine completely shut down? The engine will (should) run on the bottom plugs (incase of an open in one of the pri leads) but not very good. I have run mine on the bottom plugs after a damaged lead (spill on a gravel road) took out the uppers. Got me home. It seems logical that an ignition glich is the problem. I would check all the connectors. Also is it related to turning the bars back and forth? Its been my experience that things like coils and electronic components either work or don't. In other words once they quit thats it..done. But having said that i will add, insulation can break down and cause problems such as grounds then behave again once cooled down. If one of the pri leads has an open or a bad connector(where it connects to the stick..they are somwhat fragile to rough handling) it will take out both plugs. As I said above that has happened to me but could it related to heat? Have you checked to see if you are getting spark? (bottom and top). Just some thoughts!

Good hunting!

I hope you figure it out, let us know what happens1

[riceburner]

If dual could be the sticks ([s]doubtful[/s] HIGHLY LIKELY!).

Stick coils are designed for water-cooled vehicles where their environmental temperature (ie the temps they are exposed to) are limited to a pretty fixed range. On an air-cooled vehicle they're subjected to a much broader range of temperatures and they will break down more easily.

dashp You say you have replaced your sticks right? Well although it is possible that they have given up (only takes one),I ride in allot of heat in the CA deserts including death valley and in 130K miles I have never had a stick fail. That does not mean that they won't but there is no evidence at all that the stick coils in the R bikes do not meet design specification for aircooled applications. The 1200's have 4 and it makes no sense to put a part on the bike that is not up to specification for the designed range of operations. In very extreme situations I am sure its possible to exceed the designs parameters and you may have done just that. I doubt that as I have been in the same heat as you and had no trouble. To say that the coils were designed just for liquid cooled applications is not based on fact, just rumor.

Sounds like heat related ,but could be a connector,like the one from the hall sensor to the ecu .You have changed the sensor before so you know where that one is. Does the engine completely shut down? The engine will (should) run on the bottom plugs (incase of an open in one of the pri leads) but not very good. I have run mine on the bottom plugs after a damaged lead (spill on a gravel road) took out the uppers. Got me home. It seems logical that an ignition glich is the problem. I would check all the connectors. Also is it related to turning the bars back and forth? Its been my experience that things like coils and electronic components either work or don't. In other words once they quit thats it..done. But having said that i will add, insulation can break down and cause problems such as grounds then behave again once cooled down. If one of the pri leads has an open or a bad connector(where it connects to the stick..they are somwhat fragile to rough handling) it will take out both plugs. As I said above that has happened to me but could it related to heat? Have you checked to see if you are getting spark? (bottom and top). Just some thoughts!

Good hunting!

I hope you figure it out, let us know what happens1

Fair enough - but if you've not had any stick coil failures in 130,000 miles then you're the luckiest BMW owner I've heard of! I have them fail almost regularly.
Maybe it's the wet weather I ride in?

[kirby]

I am sorry to hear that as they are expensive. I suppose I have good luck for sure. Even with the 1150 gs (124K) no failures. (even with wet stream crossings). You do bring up an interesting question..wet wx? Don't have much here in SO CAL.You don't hear much anymore about the subject on the board. The leads do get damaged and the kit to repair them is as $$$ at the coil. I have never been fond of the system because you have to be so carefull when pulling the plugs, to not adamage the lead connectors, but it has served me and the blokes i ride with well.
I guess we try and help where we can. Part of the fun of BMW ownership..Ha!
cheers
mike

[dashp]

Thanks for all the suggestions, and to answer the ones 1. 4 plug Rockster 2. I've changed the coil sticks. 3.Checked the wireing (by the time the tank is off etc. she cools so??).
Another thing that happened was it was just 28 deg but the bike was left in the direct sunlight for a hour after a short ride and when I fired her up , rough running and would not accept any load and therefore would shut down when I try to pull away.Three hours later , no change but after dark and a further drop in ambient temp. she ran fine.
Had bikes before with wireing problems associated with handlebar glitches but that doesen't seem to be the issue here.
Maybe some Holy Water??
Peter.
KZ1000 x2
KZ900
Ducati999
68 Bonnie
TY250

[kirby]

Thanks for all the suggestions, and to answer the ones 1. 4 plug Rockster 2. I've changed the coil sticks. 3.Checked the wireing (by the time the tank is off etc. she cools so??).
Another thing that happened was it was just 28 deg but the bike was left in the direct sunlight for a hour after a short ride and when I fired her up , rough running and would not accept any load and therefore would shut down when I try to pull away.Three hours later , no change but after dark and a further drop in ambient temp. she ran fine.
Had bikes before with wireing problems associated with handlebar glitches but that doesen't seem to be the issue here.
Maybe some Holy Water??
Peter.
KZ1000 x2
KZ900
Ducati999
68 Bonnie
TY250

Peter,
That sounds like a fuel problem in some ways. Have you opened the tank filler cap to see if there is build up in pressure? Maybe the vent is plugged. Can you hear the pump run when you turn on the key? It should run a few seconds till the pressure is up to spec. If the pressure is not up to spec it will cause problems for sure.Does the fuel your using have ethanol if so how much. This effects the vapor pressure of the fuel and in extreme cases I guess could cause fueling problems.(thats a strech). You said you replaced the filter and pump, were the lines ok?Did this problem start just after you did this work or before? Are you sure the lines are all connected properly (its hapened to me!)
This is what I know about the system.
1. I have never seen an ecu fail or be affected by heat.(but not impossible) Mine has operated in 128F in death valley. Electronic devices usually either work fine or do not work at all. I have heard of them being damaged by crashes (usually the connector) Have you had yours unplugged?If so check the connector is properly seated.
2. the temp sensor in the airbox could cause the engine to run rich but not enough to cause what you describe (any black soot? out of the exhaust?
3. the oxy sensor only works in closed loop (steady throttle cruise) and will run fine without being installed.
4. The engine will run smooth (a little less power) WITHOUT the bottom plugs firing.
5. The engine will run rough with ONLY the bottom plugs firing.
6. The top plugs leads are fragile and CAN be intermittent.Affected by heat? Where they are connected to the sticks (normal fail point) Yes. I have seen them act up due to vibration and heat. If one goes intermittent it will take out both plugs.(intermittently)

Next time you park in the sun I suggest you cover the handle bars with something that will block the sun,(including the ign switch) from direct sun light. (see if that changes anything)

I love a mystery, so keep us up to date. We all learn from these things!
(But keep the holy water handy)
cheers,
mike`

[dashp]

Right then, I will check the connection to the sticks.Rode her today , cool morning it was and she ran without a bother.One thing for sure though it is definately a problem related to ambient temp rather than the actual engine temp for now its midday here in Abu Dhabi and I know even after sitting for 4 hrs she wont run( will start but rough and not accept load).
Pump runs normally, and I checked the tank vent, all good.
Really appreciate the input, what a mystery though?!!?
Peter.

[kirby]

[/img]e="dashp"]Right then, I will check the connection to the sticks.Rode her today , cool morning it was and she ran without a bother.One thing for sure though it is definately a problem related to ambient temp rather than the actual engine temp for now its midday here in Abu Dhabi and I know even after sitting for 4 hrs she wont run( will start but rough and not accept load).
Pump runs normally, and I checked the tank vent, all good.
Really appreciate the input, what a mystery though?!!?
Peter.[/quote]


Yes it is!!! But you are on track and will find it. Its frusting for sure but i agree the ambient heat is the answer. I will keep thinking. I still don't believe its the ecu. Do you have access to one you can try?Or a dealer that can read the codes?
There is a device on the market that can do that but I have never tried one.

Flash, just thought of something!!!!
There is a relay that will take out the upper plugs on a rockster (at least mine an '04) It is located under the seat in the fuze/relay box. I am going to have to go out a figure which one and get back to you. All the relays are color coded (also numbered) and can be switched around (same color or number) Possible?? you bet!

OK, just remembered this..Do you have abs? (abs is #6)
The relay in question is # 7 (the last one) So you start with the big relay ( starter,mine is yellow) and count over 6,that is the abs relay.(mine is blank as I don't have abs) the next one is #7 and that relay will take out the upper plugs! You should be able to switch the abs relay (for test, assuming you have one or swap with another with same number)..it should be the same color??) with the end one.(#7). Most rocksters I have seen have two "load relief" relays. If yours does (mine does) then there will be a relay in the #7 position which interupts power to the sticks! It's the only one that does this. My diagrams list this as "lighting" relay(just the nomenclature.) It could be that the relay is affected by heat??? I have had one of these fail!!! and it took out the upper plugs. It is something (relays) that CAN be intermitent. ( usually due to corrosion on the contacts), Check that the contacts are not corroded,if they are I would check them all!

I can't post pic on this board?? But I can send you a pic to your email address if you want. You most likely don't need that as its is easy to find!Thanks for keeping me up on this its a good one.
cheers
mike

[dashp]

Thanks Mike; I was away for a few weeksand have just returned, did try switching the relays(i do have ABS) but to no avail, took me to work fine yesterday but when I left the office at 2pm it acted up again( starts fine but after 2 min of running she bogged down)
Waited till late evening when temps dropped to 26deg C and rode home.Did notice a hesitation on acceleration and will take the injectors out .Should I clean them myself using techniques i saw on You Tube or the dealer?
Thought it seemed lean on the ride home hence suspecting the injectors.
Dash P.

[kirby]

Thanks Mike; I was away for a few weeksand have just returned, did try switching the relays(i do have ABS) but to no avail, took me to work fine yesterday but when I left the office at 2pm it acted up again( starts fine but after 2 min of running she bogged down)
Waited till late evening when temps dropped to 26deg C and rode home.Did notice a hesitation on acceleration and will take the injectors out .Should I clean them myself using techniques i saw on You Tube or the dealer?
Thought it seemed lean on the ride home hence suspecting the injectors.
Dash P.

Hey dashp,
Sorry to hear that it did not cure the problem..a real mystery!
I use a ultra sound to clean injectors. That is what most shops use. They are cheap and come in handy with other things too. I am out of ideas otherwise. The tps tells the ecu how much throttle opening you have and can make it lean if way off. Try the injectors and see what happens. If the tps is off??? It can be reset/calabrated easy enough but never heard of one being intermittent .
mike

[sweatmark]

Suggest you check fuel screen/sock, pump, filter, hose, clamps within tank.

Messy, but mission critical.

Hypothesis: possible fuel supply problem, temperature related. Either pump cavitates via vapor lock (suction side problem) or supply pressure loss due to thermal expansion of part(s) and subsequent leak.

[dashp]

Well it's 38deg C out during the day and no luck with any of my efforts, still able to ride in the evenings and early mornings though.
Tank hoses , clamps ,screen checked, all good. I will mention that 2 years ago I replaced my fuel pump with one I bought at Boneyard (US made)The quality seemed better for the fittings were metal compared to the original fittings which were plastic..
The BMW dealer here recommended that I change the said pump but that was not the problem (hall sensor).
Worked fine in all weather for a year before this problem reared its head.
Does seem like some thermal expansion in the fuel system but where?
Cavitation of the pump?Submerged in fuel so should be cool.
Electrical ?
In the mean time I will ride on evenings and hope for a component failure to identify what is acting up.
Please keep suggestions coming.
Much appriciated.

[sweatmark]

Hmm, not to bog you down with needless tasks, but what about installing a Tee in the fuel supply line in order to measure pressure via small analogue gauge?

Does your bike have a charcoal vapor recovery canister like US-spec bikes?

Ambient temperature somehow causing intake leaks? Similar to this example:
viewtopic.php?f=3&t=20709

[dashp]

Fuel pressure gauge is the next mod, could also be helpful in the future so will install.
I am also ordering a new hall sensor ,will keep you all informed if that solves the problem, hope to buy another Rockster for my other home (Ireland) so lots of parts in stock.

[kirby]

Hi!! Sorry to hear no luck. I am getting to the point that a breakedown in the insulation for the hall sensor or the sensor itself is the possible culprit. I just can't see it being fuel. (of course its possible that the pressure is fluxuating in the heat i suppose) Keep us up to date please. If I think of anything I will post!

Your sure that the ign leads are ok? When its acting up have you disconected the primaries or the bottoms? to see if it changes. Mine will run ok with just the pri plugs. but not worth poo on the bottoms only. If you pull the pri coils off the plug, put a spare plug in the coil(s) and ground them to the bike with jumper cables, that way no damage to the ecu.
Cheers,
mike

[dashp]

Well Well!
Here is the update , after years with the same problem, ie shutting down in ambient temp of 35 deg C plus I have finally solved it!
Even though the bike would crank over and start after being parked for 4 weeks at a time , the problem was the battery.
New one installed and now able to ride at all temps, not just cool winter months.
Who would of thunk????
I now have a box of good coils, sensors , plugs and a new hall sensor spare

[kirby]

Happy to hear you have found the culprit!!!

Thanks for posting.

cheers,

mike