Problems starting only when hot?

nags · 09-09-2006, 10:33 PM

My f4i starts fine when it's been sitting but sometimes after riding for a long time it struggles a little.. and sometimes wont start at all. The battery is only a few months old and I swapped out the rectifier already. Does that mean it's a bad stator or could the problem be somewhere else?

dattaway · 09-10-2006, 7:20 AM

You mean by doesn't start: not cranking or not firing?

nags · 09-10-2006, 1:11 PM

Quote:

Originally Posted by dattaway

You mean by doesn't start: not cranking or not firing?

acting as if the battery is dead

nags · 10-02-2006, 12:27 AM

bump?

Repeater · 10-02-2006, 1:23 AM

have you done the basic checks outlined in the manual? check stator resistance, voltage at battery when reved, etc.

If you ride it and let it cool does it start right up?

we need more info after the basic checks.

nags · 10-02-2006, 1:25 AM

Quote:

Originally Posted by Repeater

have you done the basic checks outlined in the manual? check stator resistance, voltage at battery when reved, etc.

If you ride it and let it cool does it start right up?

we need more info after the basic checks.

All the voltages seem ok. The battery is only about 6 months old and was brand new in the box when I installed it. If I let the bike cool down it will start no problem. If the bike is hot it just goes dead as could be. I've replaced the rectifier. The next thing to change is the stator I suppose but it just doesnt seem like a stator problem to me.. Maybe a bad battery??

Repeater · 10-02-2006, 2:14 AM

IT is not your charging system if when cool after a ride of the same period as when trying to start when hot it starts.

I would look at your starting system. when a coil (starter motor) gets hot it can short and draw alot of juice when trying to turn. it could also be the starter solenoid. check the resistance of the starter. and solenoid.

Just to clarify. how does the starter act. does it turn over easily or chug? if it starts to turn over as it does when cool check your wires and coils.

nags · 10-02-2006, 2:22 AM

Quote:

Originally Posted by Repeater

IT is not your charging system if when cool after a ride of the same period as when trying to start when hot it starts.

I would look at your starting system. when a coil (starter motor) gets hot it can short and draw alot of juice when trying to turn. it could also be the starter solenoid. check the resistance of the starter. and solenoid.

Just to clarify. how does the starter act. does it turn over easily or chug? if it starts to turn over as it does when cool check your wires and coils.

Hmmm.. I'm not sure if I know how to do all that.

Normally the starter is fine.. bike starts without a problem.. It's only if it's really hot that it has problems. Like if the bike was sitting idling for a while or something. Then it tries to turn over once or twice then just clicks.

Repeater · 10-02-2006, 4:02 AM

check if your solenoid or starter is shorted when hot. more than likely its your starter going bad. get her good and hot. make sure it is doing the bad starting issue. then check the resistance of the starter motor. if it is a short it's toast. you can also by pass the solenoid and hook up a fully charged battery right to the starter to see if it will turn over. this will eliminate any wiring or relay.

if you know anything about cars basically troubleshoot this the same way.

SomeStrangeGuy · 10-02-2006, 5:02 AM

I have seen this problem occur in 2 ways, 1 when the battery is hot (from draining or charging too fast) and the a particular 'cell' puts out a lower voltage. This could indicate a stator issue or something else going haywire, but whereas you changed the rectifier already and it's still happening I don't think this is likely.

Second as Repeater is having you chase down, where the starter gets warm and doesen't fire properly. It could be the bearings are toast and putting more of a load on it and it's drawing the batt. down super fast, or the windings are heating up and arcing, which is also ugly and means new starter/rebuild.

If you're not comfortable checking the starter yourself, it may be easier to pull it and take it to a starter/alternator shop. Those guys would be glad to run through it for you for a few bucks or they probably won't charge you anything if you end up needing it rebuilt ( and go that route with them ). I haven't priced an F4i starter but i'm assuming a rebuild is less scratch then new (anyone?).

I had a problem like this in my old truck, previous owner spent about 500$ replacing everything electrical and still had problems starting it up. I got it and at the advice of others replaced the starter itself and poof - no more issue.

Do you have a shop manual and/or a camera?

nags · 10-02-2006, 4:37 PM

Quote:

Originally Posted by SomeStrangeGuy

I have seen this problem occur in 2 ways, 1 when the battery is hot (from draining or charging too fast) and the a particular 'cell' puts out a lower voltage. This could indicate a stator issue or something else going haywire, but whereas you changed the rectifier already and it's still happening I don't think this is likely.

Second as Repeater is having you chase down, where the starter gets warm and doesen't fire properly. It could be the bearings are toast and putting more of a load on it and it's drawing the batt. down super fast, or the windings are heating up and arcing, which is also ugly and means new starter/rebuild.

If you're not comfortable checking the starter yourself, it may be easier to pull it and take it to a starter/alternator shop. Those guys would be glad to run through it for you for a few bucks or they probably won't charge you anything if you end up needing it rebuilt ( and go that route with them ). I haven't priced an F4i starter but i'm assuming a rebuild is less scratch then new (anyone?).

I had a problem like this in my old truck, previous owner spent about 500$ replacing everything electrical and still had problems starting it up. I got it and at the advice of others replaced the starter itself and poof - no more issue.

Do you have a shop manual and/or a camera?

Well, it always starts when cool. Now today I go out and try to start it and it was deader than dead. I put the battery charger on it for just a few minutes. Start it up (struggled) then rode it around for about 20 minutes. I noticed the temp on the gauges never went past like 130. So I come back in the driveway and the thing is hardly idling then died. As soon as the motor went off then the temp jumped to where it should be. Tried to start it again and it was dead.

nags · 10-02-2006, 4:39 PM

It seems like whatever is causing this is the same thing causing my inconsistent rpms.. Hopefully I can take care of 2 things at once.

And yes, I have both the manual and a camera

nags · 10-02-2006, 7:31 PM

It seems like its getting no spark or no gas or something

HyperBuzzin · 10-03-2006, 8:09 AM

Is it a standard wet cell battery, or a maintenance free one?
If it is a standard one, have you checked the fluid level in it?
A battery low on fluid will many times start the bike fine when cool, but not hot.
Also, even 'new' batteries have been known to have bad cells, even right off the shelf.

mathyoomay · 10-03-2006, 9:23 AM

nags- I have the same problem with my F4. with my bike it seems as if it gets too hot then it will act weird or lose power and not turn over unless I let it cool down for awhile. one thing i also noticed is sometimes while driving the city, sstop and go traffic, it will get hot and sometimes feel like it is going to stall. we gotta figure this out, keep me updated if you find a solution.

nags · 10-03-2006, 6:09 PM

Quote:

Originally Posted by HyperBuzzin

Is it a standard wet cell battery, or a maintenance free one?
If it is a standard one, have you checked the fluid level in it?
A battery low on fluid will many times start the bike fine when cool, but not hot.
Also, even 'new' batteries have been known to have bad cells, even right off the shelf.

Its a YTZ10S

I'm currently looking for a new stator and battery. And possibly fuel pump

SomeStrangeGuy · 10-03-2006, 8:38 PM

For a batt. be sure to check wal-mart...cheap/decent batts there.

Repeater · 10-03-2006, 9:01 PM

Instead of replacing parts i would go through the steps in the manual.

You can check your stator by measuring the resistance or check the voltage, 5 to 6 k rpm, it should be around 14.2 volts. if it is your charging system is fine.

you stated you have an inconsistant RPM issue? This can be caused by many things like coils,ecu, plugs, wires, and etc. i would check your coils (page 441 of your manual).

you may have a couple issues. as far as starting when hot. does the starter motor turn the motor over easily (even if it does not fire). half step and start a process of elimination. if you know anyone with the same bike.. borrow some parts like the ecu. ( i know that is tough to do though)

good luck and let us know what your measurments are.

nags · 10-03-2006, 11:20 PM

Quote:

Originally Posted by Repeater

Instead of replacing parts i would go through the steps in the manual.

You can check your stator by measuring the resistance or check the voltage, 5 to 6 k rpm, it should be around 14.2 volts. if it is your charging system is fine.

The bike will not start at all. It's got plenty of power.. Everything is lit up and its trying to start.. It just never turns over

nags · 10-03-2006, 11:22 PM

Quote:

Originally Posted by Repeater

you may have a couple issues. as far as starting when hot. does the starter motor turn the motor over easily (even if it does not fire). half step and start a process of elimination. if you know anyone with the same bike.. borrow some parts like the ecu. ( i know that is tough to do though)

good luck and let us know what your measurments are.

When I was having that problem it was acting just as if the battery was dead.. Would try to turn over then the lights would all dim then it would just click

HyperBuzzin · 10-08-2006, 12:54 AM

Quote:

Originally Posted by Repeater

You can check your stator by measuring the resistance or check the voltage, 5 to 6 k rpm, it should be around 14.2 volts.

Just posting how I understand stators....

Don't stators put out AC voltage?
If checking at the battery it would be DC volts. The stator on my bike puts out about 40 or so volts AC and the regulator/rectifier changes it to DC.

I'm a certified machinist, not a certified wrencher, so like I said, that's how I understand stators to work.

Repeater · 10-08-2006, 2:10 AM

Yea it does put out ac, but if you check at the battery you check the whole system. sorry i should have been more percise about DC and what was being checked.

any updates nags?

nags · 10-18-2006, 6:04 PM

Quote:

Originally Posted by Repeater

Yea it does put out ac, but if you check at the battery you check the whole system. sorry i should have been more percise about DC and what was being checked.

any updates nags?

Just got back into town and was expecting to have some parts waiting for me but the dude had refunded my money. So now I have no parts to try.