Motorcycle Questions? Ask a Mechanic.
Hi and thank you for your question.
The key to reinstalling the starter idler gears properly is to put them in first without the shaft and turn them until the bore in the gear lines up with the bore in the case, then install the shaft. To ensure the shaft is fully seated rotate the shaft as you seat it in the case. If oil gets trapped in the case bore it will create a spring back effect as you try to push the shaft into the case, making it feel like there is a spring trying to push the shaft back out. By rotating the shaft when you feel that it will allow the oil to escape from below the shaft and seat fully.
If you have any more questions please feel free to ask.
I am not clear on what the problem is then. You said the side cover wouldn't go on because the idler gear for the starter came out. If you were able to get the idler out back between the starter and the flywheel and get the shaft for the idler in, the cover should go right on. In fact, be careful that the cover doesn't snap into place because of the magnets on the flywheel. If the cover isn't going on completely and you think it has something to do with the idler gear, take it out one time And try putting the cover on without the idler gears and shaft. If it goes all the way on without the idler then you know that is where the problem lies. If it is still not going on all the way, something else is hanging you up. Let me know where you are at on this.