FXR having problems running, suspect electrickery is to blame

[who_me_33]

The following bits are just cut and pasted out of the post under engine, as it is seeming to be an electrical fault.
My FXR150 has developed a problem where it will not run when it is up to temperature. It will run fine when it is cold, and has no problem revving when it is cold. But when it has been left to warm up, it is very reluctant to start, and when it does, it will not rev. I have cleaned the carb, and replaced the plug (both at the same time as the problem first came about an hour before my full test was scheduled). There has been no other problems with it in about the last year, and the only thig that happened before the problems came is it sat outside in the rain in for the morning, while I was at uni (this is the day the problems came). It has however had a chance for any thing that might have been wet to dry out, and the problem is still there. Does anyone have any ideas on where to start looking for this problem.
Then went fine for 2 weeks, the next post is here.

Does anyone have any ideas. It started working fine, and was like that for about 2 weeks, but then started giving problems again. It now will not run properly at any temperature. As soon as you give it a reasonable ammount of throttle it dies (if I managed to get it started in the first place, is reluctant to start at time, other times it starts fine). I have sprayed ether into the carb, and that doesnt help with the starting (rulling out carberation). I have been over all the connectors at the back of the bike (where the ignition module is), and there was only one with some water in it. This appears to be the main ignition box, it is an expoxy sealed box. There was also a grease like substance in the connector (clear, kind of like vasoline). I have sprayed crc on that connector to try and displace the water, and it doens't appear to have helped. Does anyone have any other ideas that I should try.


Ok, I'll clean the carb again. Also I have had a look at the earth connection to the coil, and it was not too bad (corroded slightly on the outside, still a reasonable surface where it connects (and I also took to it with a wire brush to be sure). Where are the other earth connections to look for, (other than at battery). Are there any on the engine that I need to look for.
Nick

Just cleaned the carb again. There was no water in the fuel in float bowl (I drained it into a clear glass container). Dismantled the carb, and cleaned it. Put it back together, and there was no change in the situation, (still reluctant to start at times, dies when it gets a reasonable ammount of throttle). Then went over the earth connectors, that I could see, and took to them with a wire brush and contact cleaner. Cleaned and dried the connector to what I bleieve to be the ignition circuitry, and still nothing. Also I am starting it after I do each small step, just to make sure I don't miss what fixed it. Measured the resistance of the coil, and it was reading about 1 ohm on the 12v side of the coil, and about 20K on the output. Does that seem right.

Can anyone see if I have missed anything obvious to check, in regards to the electrics, or if it is something that you have seen before. Also how does one re-seal connectors, as I have now washed all the sealant of the connector to what appears to be the ignition circuitry, (and am reluctant to use silicone, just incase it needs to be repaired again.

[CookMySock]

Pull the fuel hose off the carby and see if fuel runs freely from the fuel tank.

Steve

[who_me_33]

Pull the fuel hose off the carby and see if fuel runs freely from the fuel tank.

Steve

Done, and plenty of fuel flow (for this engine any way, I'm sure there are plenty of engines that it wouldn't be enough for). However as pointed out to me (almost simultaneously by a family friend, and someone in the other thread), I checked the points. Points appeared to be fine, but what I can only assume to be the alternator appears to be knackered. I am assuming that the black deposit should not be there (it is a solid deposit, not a gunky type one), and will try and see if the problems are still there with any un-necessary load removed (ie, disconnect the head lights). (And yes, the gasket is now damaged as well (it can be seen in the pic, this will be fixed before I go back on the road with it, will not worry about in the mean time, while I am still fault finding, unless it is a problem (ie, losing oil)).
And if it is the problem, it may very well indicate why it has been so bloody hard to find. At the moment, I cannot kick over the bike, so have had it on charge while working it, and it gets a nice fresh charge. Problem dissapears. Take charger off, run it, and the battery slowly runs down, then eventually to the stage of being flat enough to be a problem. So now to look into testing of an alternator.

[who_me_33]

Just put it back together, refilled the oil, started it, and it is 12.5v at the battery when running. Shouldn't I be expecting to se about 13.5-14v when it is running.

[xwhatsit]

I checked the points. Points appeared to be fine, but what I can only assume to be the alternator appears to be knackered. I am assuming that the black deposit should not be there (it is a solid deposit, not a gunky type one), and will try and see if the problems are still there with any un-necessary load removed (ie, disconnect the head lights).

No points on an FXR -- unless you mean the ignition pulser, which kind of does the same thing.

The alternator (that bit that you've taken the photo of is called the stator) doesn't look horrific, but it could be the problem. A manual would have specific values to check with a multimeter, but one you can do right now is to check continuity between the three phases (I learned about this when I had hard starting due to a knackered stator myself ). There'll be three wires coming off the stator. Each corresponds to a different wire running through the stator. If it has burned out, then the wires will be able to conduct between phases -- which will drop the output. So just check continuity between the three wires, try all combinations. If there's any continuity between them you need a new stator (or this one rewound, I've seen it advertised as a service for less than $200).

It might be worth mentioning that disconnecting the headlight won't help (provided it's a three phase alternator, the modern 12V systems nearly all are now aren't they?), as usually the ignition runs off one phase all on its own. As was explained to me, three phases means basically three alternators wound up together into the same unit, so drawing current off one won't affect the others.

Good luck! I empathise with your frustration having had a similar headache myself trying to track down the problem!

[who_me_33]

Gave the bike a good charge last night, and the bike is running no problems now. Going to flatten the battery a bit, and see if the problems come back. Regardless, time to cancel my test (again, this test is really eluding me, and I haven't even sat it yet), as it is seeming less likely that the bike will be back running by Tuesday.

No points on an FXR -- unless you mean the ignition pulser, which kind of does the same thing.

Ok, so is it points on older bikes (without electronic ignitions).

The alternator (that bit that you've taken the photo of is called the stator) doesn't look horrific, but it could be the problem. A manual would have specific values to check with a multimeter, but one you can do right now is to check continuity between the three phases (I learned about this when I had hard starting due to a knackered stator myself ). There'll be three wires coming off the stator. Each corresponds to a different wire running through the stator. If it has burned out, then the wires will be able to conduct between phases -- which will drop the output. So just check continuity between the three wires, try all combinations. If there's any continuity between them you need a new stator (or this one rewound, I've seen it advertised as a service for less than $200).

Just measured the resistance of it, and it is ~2 ohms between any 2 of the wires (I dont have a manual, so cannot tell you right now what it should be, I am asking someone on the FXR150 forums to have a look to see what it should be).. I also fired the bike up, with the stator disconnected, and between Pins 1-2 on the connector was ~20v, 1-3 20v, and 2-3 ~5v. Shouldn't they all be the same.

It might be worth mentioning that disconnecting the headlight won't help (provided it's a three phase alternator, the modern 12V systems nearly all are now aren't they?), as usually the ignition runs off one phase all on its own. As was explained to me, three phases means basically three alternators wound up together into the same unit, so drawing current off one won't affect the others.

Good luck! I empathise with your frustration having had a similar headache myself trying to track down the problem!

But if it was only running of the battery (ie, the stator not charging), doesn't the ignition run off the battery initially, until the stator is charging (ie, engine running). Or am I getting something confused here.

EDIT
Once I discharged the battery a bit, the problems would re-appear. Running voltage at idle is 11.9v, and when reving is about 12.5v. When I drop the revs, the battery voltage steadily falls over about a minute to 11.9v. That 12.5v while reving is low isn't it.

[who_me_33]

Changed the battery (under the advice of the dealership), and it appears to have solved the problem. Now reading 13.8V while the bike is revving. I will keep you posted as to wether or not it gives me any problems.

[Pumba]

Just a word of warning, the FXR does not require a battery to operate. you should be able to disconect the battery, start it (using the kick start NOT the electric starter motor) and run fine.

I suspect you still have a problem with your stator that is messing with the charging system which has resuted in your battery shitting its self, and this may possibly occur with your new battery, if the real problem is not fixed.

[who_me_33]

Just a word of warning, the FXR does not require a battery to operate. you should be able to disconect the battery, start it (using the kick start NOT the electric starter motor) and run fine.

I suspect you still have a problem with your stator that is messing with the charging system which has resuted in your battery shitting its self, and this may possibly occur with your new battery, if the real problem is not fixed.

So other than disconnecting the battery, and seeing if it will run, what can I do to see wether or not there is a problem with the charging system. First stop would appear to be be check the voltage at the battery terminals, but other than that what should I be looking at.

EDIT The old battery was about 2.5 years old anyway, and was used most days, except for a period where it sat for 6 months between sept 08 and March 09.

[Pumba]

Disconnecting the battery and seing if it causes any problems would be my first step.

Apart from that from that it is a matter of checking the voltages with a muti meter, I dont know what they should be, and to be perfectly honset electrickery scars the shit out of me (you cant see it but by fuck it hurts, and can really ruin your day when all the smoke escapes from the system) so I am no expert.

[CookMySock]

Yeah that stator looks a bit toasted. Ironically, mine has just done the same thing, so I'm either rewinding it myself, or getting it sorted otherwise.

Steve

[who_me_33]

Yeah that stator looks a bit toasted. Ironically, mine has just done the same thing, so I'm either rewinding it myself, or getting it sorted otherwise.

Steve

Just been looking at another thread. And the contents of http://www.electrosport.com/technica...ding-guide.php
From the tests, it says rev it 2500RPM and measure charging voltage. About 12.9 (slightly low), but about 13.4 at 3000, so I am not too stressed here in the mean time (it is also below 14.5 at 5000RPM).
On the test of the stator, it says rev it to 5000RPM and measure the stator voltages. 2 of them are ~50, and one is about ~40. So yes, the stator is knackered. But in the mean time, I am going to not cancel my full test, and do it on that bike, and then sort the stator after that. Ill just keep an eye on battery voltage levels, and make sure they don't dip below about 12V when the bike is off. Its a risk I know, but it is one I am willing to take.

[CookMySock]

fired the bike up, with the stator disconnected, and between Pins 1-2 on the connector was ~20v, 1-3 20v, and 2-3 ~5v. Shouldn't they all be the same.

Yeah something is borked. With the engine stopped, check the resistance from each pin to the bikes frame/ground or to the negative battery terminal - it should be open-circuit. My guess is it's not open circuit, is quite a low resistance like 1-2 ohms. If so, you have a short-to-ground fault inside your stator.

After you have done your license on it (brave man - I wouldn't - borrow a bike!) and if you want to rewind it yourself, I'm just rewinding mine if you want to compare notes. Mine has done the exact same thing. Must be something in the water.

Steve

[who_me_33]

I would borrow a bike, if only I knew someone with a <250cc bike (am still looking into that possibility). BUt in the mean time, I'll just have to keep the revs up a bit (about 2000rpm keeps it above the voltage that the battery is at when the bike is off so is not discharging at anything above 2000rpm)., so And comparing notes would be good, it will probably make a good mid year break project (by my estimate there shouldn't be much more than 8 hours work in it for someone who has done it be fore ($200 for a rewind on trademe, assuming they are charging at least $25 per hour). So considering I have never done it before, I would be thinking about 15 hours, and then parts.

[CookMySock]

The two tricky parts are, figuring out exactly how it's wound and making a diagram, and getting all the old windings off. After that its just wire, epoxy, and soldering. Getting those screws out can be a bitch too.

Steve