starting issues

[commute365]

I've got a 2003 FJR1300 that after riding for a while when the bike it hot it is very difficult to start. The starter sounds like it is turning very slow but if I WOT it cranks. I dropped it off at a shop to be looked at and they told me everything looked good and they couldn't replicate the problem. I've checked the battery voltage and it is around 14v when running. Any ideas as to what the problem may be would be greatly appreciated.

 

[Fred W]

It is fairly common that starting problems on the FJR first show up when the engine is hot. There are several theories as to why that happens, but no definitive ones. Could be the engine compression increases when warm, or the starter motor magnets becomes weaker when jheat soaked, or any of a number of other hair brained ideas.. Suffice to say that it is harder on the starting system when the engine is fully warmed up up than when it is cold.

That said, the first thing to rule out is the battery capacity. The 14V you measure at the battery with the bikle running is the charging voltage from the alternator, not the battery internal voltage. But 14V is a good charging voltage so at least we know that (with a good battery) it should maintain a full charge as you run the engine.

Measure the battery voltage before you start the bike. It should be 12.6 to 12.8V DC if the battery is taking a full charge.

Attempting to measure the voltage at the battery while actually starting is fairly pointless, since we already know that the voltage is dipping too far. The dipping voltage can be caused either by a bad battery (low capacity) or by a bad starter motor (pulls too much current), so measuring that voltage doesn't tell you much.

Instead,.you can get the battery load tested independently at a shop. The load tester will put a known load on the battery and pull a specific amount of current (amps) and they will measure the voltage at that load to see if the capacity is up to spec.

But given the consumable nature of batteries, if your battery is more than about 4 years old, you might want o just spring for a new battery to see if that resolves the problem. The next most likely problem is the starter motor is at fault, and that is a far more involved process to access and repair.

 

[Canadian FJR]

Give that '03 some TLC and get it back to good health. Not many of us left.

When was that last time that the it had a good service - air filter, valves, throttle body sync?

Canadian FJR

 

[lele]

do u ever check valve timing and valve clearance?

the spark plugs are ok?

 

[Donal]

I would be suspicious of the starter motor.

If you have access to a clamp-on ammeter, try measuring the starter current.

It should be around 60-80 amps, if it is significantly higher you will need to service or replace the starter motor.

 

[Fred W]

I see no reason that spark plugs, valve clearance, air filter or TBS would cause the starter to turn over slowly when hot.

Note, that the clamp on ammeter must be a DC capable one. Many clamp-ons (like the one I own) are only good for AC and would be of no help here. Also, the current draw test is only valid with a known good battery.

 

[commute365]

Guys thanks so much for all the input. I think I may just replace the battery and see if that helps.

 

[C&C]

Battery (check) first, starter (second); heat soak does appear to be a factor. Also, leaking injector could help complicate compression lock, if that is the cause. But you're right; replace the battery, especially if determined weak.

 

[mcatrophy]

Guys thanks so much for all the input. I think I may just replace the battery and see if that helps.

Remember a new battery may well mask the effects of the higher current draw of a failing starter motor. You'd be well advised to make the current measurement whether or not the new battery gives you better starting performance.

 

[commute365]

Guys thanks so much for all the input. I think I may just replace the battery and see if that helps.

Remember a new battery may well mask the effects of the higher current draw of a failing starter motor. You'd be well advised to make the current measurement whether or not the new battery gives you better starting performance.

Good point

Give that '03 some TLC and get it back to good health. Not many of us left.
When was that last time that the it had a good service - air filter, valves, throttle body sync?

Canadian FJR

All regular maintenance I've done at regular intervals except the valves. When i bought the bike it had 28-29k miles so I assumed the valves had already been checked. Also the shop rode it and looked it over and never mentioned it might need valves done.

 

[Fred W]

1st valve check was supposed to have happened at 26k miles. I do mine on the 25k's as it's easier to keep track of that way.

In all likelihood the check would not have resulted in a need to reshim anything. As you can see in the valve check vs. adjust poll only 10% of shops find a need to reshim at the first check.

Somewhat interestingly almost twice as many (20%) of Do-It-Yourselfers find a need to reshim on the first check. Take from that what you will.

 

[audiowize]

I had this exact problem with my '03. I would ride up to the line to get on the ferry, shut the bike off, then start it back up a few minutes later with great difficulty. The clock would reset to 1:00 when an event like this happened.

A new battery solved the problem for me.

 

[K_Flyer]

I'd recommend the Odyssey batteries as the one in my BMW was going strong after 5 years and would crank the bike over much faster than others I'd tried. However, I just checked and Odyssey does not offer a battery for the FJR. They do for a lot of other Yamaha's, but not the FJR.

 

[audiowize]

 

[mech 1 twa]

I subscribe to a motor mag. Motorcycle Consumer News, great mag. It has a section called down time files, problems people are trying to fix.

Someone had a FJR wouldn't crank or cranked slowly when hot. Another subscriber said he found oil in his starter motor, a seal was leaking causing his FJR to have the same issue. I can find the Mag.issue but I know I read it. Don't know if that"s your issue or not. He replaced seal and took starter apart and cleaned it, worked after that.

 

[ionbeam]

...a FJR wouldn't crank or cranked slowly when hot...found oil in his starter motor, a seal was leaking causing his FJR to have the same issue...

Brush wear, clogged & shorted commutator bars and oil seal leaks and known starter motor failure modes. No matter what, once the starter shows excessive current draw it has to be removed and repaired or replaced. Why the starter failed is only a matter of curiosity. And, us Forumites are a curious group

 

[PhilJet09]

As a related side note, does anybody have a part number or source for the oil seal on the starter? It's not on the parts diagram.

 

[mech 1 twa]

I only remember what I read. I see no seal in starter parts list. A couple of O- rings but nothing is listed that you can order except complete starter .

2 O rings seal starter housing, smaller one seals case from external leak.

 

[PhilJet09]

Yep, I've seen that, but there's an oil seal the seals the actual shaft of the starter. This is the one that eventually fails and allows oil to seep in and mix with carbon.