Right, bit of an issue with my 2002 ST4s (996). I thought yet another starter solenoid had died but it seems the issue is more than that. When I press the starter button the solenoid clicks but nothing happens. The starter motor does not turn at all, and consequently the engine does not turn over. I took out the starter solenoid today, which was replaced within the last two years, and cleaned up the contacts on it, and on the starter motor. I put it all back toge3ther and had the battery fully charged from a trickle charger. Now, there is a full 12.5v getting to the solenoid. When I press the start button, the solenoid clicks and there is 12.5v going to the other pole. Then I tested the pole at the starter motor and it appears to getting 12.5v volts too. So I'm baffled now. I haven't tried to bump start it. I did wheel it a long with the clutch in while in first and then let the clutch out to see if the there was something locked or such, but it didn't seem to make any difference. The bike had been in daily use. A
Sounds like the problem lies in the starter, a sticking brush perhaps. Try bridging the solenoid terminals with a big screwdriver (beware of the sparks). That should definitely get 12v to the starter and if it still does nothing the fault's inside it although it's worth checking for a poor connection at terminal on the starter. Beware when loosening the nut, if the post wants to turn, hold it with a pair of pliers or a mole wrench. If it does turn it will pull the internal wire from one of the brush holders.
Thanks for that. It does seem to be a starter motor issue. The post on the starter motor did seem to have some play in it but it definitely did not turn and tightened up nicely. Is it possible to change the brushes in the motor? AFAIR, to take the starter motor out requires removing the LH cover and fly wheel assembly. Is that correct? A
It is possible to change the brushes with the motor insitu but not recommended. To take the motor off you have to remove the LH cover but not the flywheel. You can get access to the retaining screws through the holes in the intermediate pinion.
UPDATE: turns out my main issue is a buggered starter motor. I bypassed the solenoid and there isnae a kick out of the starter. Brush kit on order for a rebuild. A
Finally got a chance to sort this out. Got a starter motor brush kit from Wemoto and, after a bit of faffing, got it sorted and back on the bike. The brushes were down tot he wire and the commutator was filthy. So all required a good clean and then the rebuild with the new back plate and brushes. However, also took the opportunity to change the oil and coolant, clean the air filter, gap the plugs and check the belt tension. I also replaced a load of busted well nuts. So she should now be singing sweetly when she is all back together. Of course, I wrung out two of the allen studs on the genie cover but a torque head removed one and had to drill the other, but all OK, as my local breaker has a free service called the miscellaneous bolt box. 20 minutes of rooting about while having a chat yielded the required studs and I'm back in business. Just need to re-assemble now and then ride the thing. A
It lives! And starts a damn sight easier than it used to. All reassembled, serviced and only 6 well nuts replaced Rock on! A
I did not, for one moment, intend to imply that you wouldn't ride it once the weather has got crap... It's just more enjoyable if it's not crap...
Well, I spoke to soon! The bloody thing stopped again. I thought poor cold starting was due to fecked plugs, as they were in there for more than 20k miles (but they were iridiums), but then I got some new ones and the starter failed again. So, I took it out again and found that the commutator is indeed fucked. The new brush kit I had put into it was worn nearly half way through the bushes, with only a week's use. The commutator surfaces are just so worn that they are eating the brushes. Buggery bollocks. A new starter it is. A
Do you know anyone with a lathe that can skim the comutator for you and undercut the insulators? Not sure if small local engineering companies that used to do this sort of thing actually exist anymore...
Cheers@JR45, that's a good suggestion but I found a crowd online called Electrex World who do a pattern motor for £99. I rang them up said I was in a hurry and I had three day delivery from order for only £19. Definitely one to look out for. Anyways, went to work on it today and she started easy, ran beautifully and feels bloody fit. I changed the fuel filter too as I read somewhere else that when the fuel pump is under strain, itr can cause all sorts of electrical gremlins. Well, today, in 5th, cruising at 120kph, with the dipped beam on, the flash/pass light did not make it drop onto one cylinder, as was happening before. The two things may not be connected but a win is a win So, with clean air filter, new plugs, tensioned belts, new fluids and filters, it all adds up to a machine that feels factory fresh. Huzzah! A
