2018 300ec starter issues

[Doc Brown]

I follow this thread since I had my first 2018 GP. I could not solve the starter issues and bought a 2019 EC and its starter worked flawless from day one till I sold it.
On my last 2019 EC the starter worked 47 hours and gave up today. I will start an own thread for this problem.

Lets go back to the 2018 GP:

When I tried to find the problem I took the starter off and I also took the starter off my friends GP 300 2018. His bike has the known problems since day one, his never started with the e-start when the engine is cold, but it works as soon as the engine is hot. He had the CDI flashed, added thicker cables, grinded contact surfaces and so on, but nothing helped. He also changed the starter button. My starter burned so I installed his starter motor on my bike (2019 EC 300). To align the pinion inside the cover with the starter shaft I turned the pinion (20) with my finger and it had almost no resitsance, I also could turn the starter axle (16) and the bendix (12) easily.

I tried the same on his bike and could not turn the pinion (20) with my fingers. I had to insert the shaft of a disassembled starter and could turn it using some force.
Do you think that this could be the problem why the starter doesn't crank the engine? I have no clue why there's so much resistance but we will find out soon.

I will also tell him to weld the axle (16) and the pinion (17) together but first need to get the whole thing apart.

 

[gg3]

Got side tracked on another starter thread, have compiled it here.
Tonight I taped the bendix fully extended,put it in,put the old starter spline in & tried turning it by hand.Turns much easier than expected,not much load at all.But I am turning it very slow compared to a starter motor,so operated the kick by hand slowly.Everything turned without binding,real smooth?But as soon as I pushed the kick harder to normal operating speed,it jammed.On inspection the bendix was moving away from the pinion gear & locking crown to crown.Keep in mind the bendix cover is off so understandable.With the cover on slow rotation all good,fast rotation locked up.
With the cover off I held the bendix with a rag,pushing in & up to keep it tight against the pinion gear.Then hit the starter(don't try this kids),it turned over really well.Then locked again as I was concentrating on not getting my fingers dragged into the bendix. Video link below of hand/kicker rotation.
https://youtu.be/-QsvLt9rT1s
I have had the case off ,fully extended the bendix to check for any contact with the case & then measured case face to bendix gear & case face to ring gear (excluding gasket).Bendix seems close enough to fully engage & clear the case. In my case the starter worked fine for a long time before playing up.The gears on the pinion & bendix look in good condition & mesh together well. I think it is the pinion shaft & bendix shaft don't sit exactly parallel & close enough together. Possible wear at each end of the bendix shaft housing? As I have replaced the bendix cover with an AS3 cover it is most likely the shaft housing in the case. With bendix out & bendix cover off,& holding the starter button, the pinion shaft spins freely with no visible wobble, looks straight & true so am going to eliminate that shaft as the problem.
New OEM bendix due next week. Current one possibly not straight.

 

[gg3]

Put an OEM new bendix in (that cost more than unicorn shit!!).No different,so it wasn't the bendix. On to the next part.....

 

[Gasser Nate]

I follow this thread since I had my first 2018 GP. I could not solve the starter issues and bought a 2019 EC and its starter worked flawless from day one till I sold it.
On my last 2019 EC the starter worked 47 hours and gave up today. I will start an own thread for this problem.

Lets go back to the 2018 GP:

When I tried to find the problem I took the starter off and I also took the starter off my friends GP 300 2018. His bike has the known problems since day one, his never started with the e-start when the engine is cold, but it works as soon as the engine is hot. He had the CDI flashed, added thicker cables, grinded contact surfaces and so on, but nothing helped. He also changed the starter button. My starter burned so I installed his starter motor on my bike (2019 EC 300). To align the pinion inside the cover with the starter shaft I turned the pinion (20) with my finger and it had almost no resitsance, I also could turn the starter axle (16) and the bendix (12) easily.

I tried the same on his bike and could not turn the pinion (20) with my fingers. I had to insert the shaft of a disassembled starter and could turn it using some force.
Do you think that this could be the problem why the starter doesn't crank the engine? I have no clue why there's so much resistance but we will find out soon.

I will also tell him to weld the axle (16) and the pinion (17) together but first need to get the whole thing apart.

Yes definitely, the whole bendix, bevel gear and reduction shaft should turn by hand very easily. The small reduction shaft has a screw holding the bearing and gear on it, it can back out and lock the shaft to the cover, (number 26). All bearings should be smooth and turn easily. Do not accept any that are not smooth.

 

[Doc Brown]

Cheers Nate! Many thanks, we will check that. The difference in turning resistance between his and my bike is significant. Mine is so easy to turn and his needs quite some force, no way to turn it with the fingers.

Ist it necessary to take the ignition cover off to get the lower pinion gear and the litte shaft out?

 

[Gasser Nate]

It is easier to take it off, you can localise the heat required for its removal. I have a dowel removal tool that fits the shaft nicely as in can take a little slide hammering to get it out.

 

[farmerj]

Cheers Nate! Many thanks, we will check that. The difference in turning resistance between his and my bike is significant. Mine is so easy to turn and his needs quite some force, no way to turn it with the fingers.

Is it necessary to take the ignition cover off to get the lower pinion gear and the little shaft out?

Yes Doc, remove 4-5 bolts and the cover will come off. 5 min. or so job. My recollection is that you have to remove the starter gear before the pinion gear will come out (if my memory is faulty, I'm sure someone will correct me!).

Remove the circlip (#22) and then use a heat gun on the stator cover around bearing #21. Then tap the case on a solid surface - the bearing should pop out, and the starter gear can be removed. Then you can pull out the pinion and gear. If the pinion bearing (#18) needs to be replaced, heat the outside of the case and tap on a solid surface as you did for the starter bearing. Some guys have made pullers of sorts - the heat gun worked for me.

Screw #26 is known to back off and create issues; per the MotoCenter video, welding the gear to the shaft is recommended so that the gear can't spin on the shaft.

Also, even though there is a machined lip and circlip (#22) that should space the starter and pinion gears correctly, I have experienced and know of others who have found that sometimes they are too tight - then the gears don't mesh correctly. I stuck a thin punch in there and tapped the starter gear "up" toward the circlip just enough so that everything could spin smoothly by hand.

This may be your problem, and you may not need to disassemble everything btw.

Also, you may need a new stator cover gasket when you reassemble.

Have success!

Jeff

 

[farmerj]

Sorry Nate, didn't see that you had already replied!

 

[farmerj]

Also Doc - it would be very interesting to hear what happens if you take your good 2019 stator cover & internals and bolt it onto the hard-starting 2018. As I've written elsewhere, I'd like to try that sometime and it would confirm that the problem is in the 2018's case/bendix/gear system if the 2019 part works well.

Jeff

 

[Doc Brown]

Thanks guys for all the assistance, much appreciated. I have to wait and see what the owner of the 2018 Gasser says and I will wait until he has time so that we can do it togehther.

I need to order a gasket as the 2019 gaskets are different. Unfortunately my 2019 has the same problem now but I'll report that in the other thread.

 

[Iakovos1]

Anybody have any thoughts on this kit https://www.ebay.com/itm/Starter-ki...286015?hash=item3669aea07f:g:ztgAAOSwZXRfUQrv

 

[gg3]

This is how it should have been made.It would solve my problem of lateral movement between the bendix & pinion shafts.If the new starter on order doesn't make any difference(which I don't think it will),my next step is to do some machining & fit a bush each end of the bendix shaft.This guys idea is much better....in theory.

 

[gg3]

My second cheap KTM copy starter arrived.Did the 180 degree rotation to change rotation to clockwise & tried it.
https://youtu.be/frbNoDAyVac
Still not turning over great but worked.Recap of process-
All positive & negative leads replaced with bigger cable & clean all contacts & earths.
Ran new earth to starter motor mount.
Replaced stator(was ok in hind sight).
Lithium 240cca battery fully charged 13.4v
New AS3 bendix cover & doubled the gaskets.
Welded bendix shaft then got a OEM new bendix (which came welded).
Checked the bevel gear parts 17 & 20 engagement & greased.Checked bevel gear bearings are smooth & whole assembly with pinion gear operate smoothly.
filed & cleaned up sharp edges on the flywheel/ring gear.
Spent countless hours with shims,washers,gaskets & gear marking grease to check & correct engagement of parts.I am fairly convinced the main problem is the pinion gear & bendix bind up when under load.
I am thinking there are new bikes with the pinion shaft & bendix shaft not running parallel and/or distance apart not correct.Other bikes as they get hours up the shaft housings are getting out of round or sloppy causing binding.Both are made worse by small cables not getting enough power to the starter & the constant binding & load is burning out the starters.
The last starter I had I ruined by constant testing.It still spins up fast but has lost torque.I'm sure the new one will give up as well after a while.I am going to try fitting a low friction bush into each end of the bendix shaft housings & then machine down the shaft ends to fit.

 

[GasGas]

I have been struggling with the button start for the last year or so and finally replaced my battery with a 240 cranking amp unit from Antigravitie batteries. After struggling for so long with the stock battery brand and my old Antigravity 8 cell it was some nice to push the button a couple times on a cold motor and have it running. Towed the bike for an hour on an open trailer at 5 degrees C and it started no problems again. The rest of the day riding it was just touch the button and the motor was running. If you are struggling with your bike do your self a favor and just get a battery with 200 plus cranking amps. I will never own another push button dirt bike without one.

 

[Doc Brown]

Check this out, its the bendix cover of a new Rieju 300

 

[SpirosZ1000]

Check this out, its the bendix cover of a new Rieju 300

Already on my bike and works like a charm but my old starter is gone and currently waiting for a new arrowhead unit.

 

[Doc Brown]

Already on my bike and works like a charm but my old starter is gone and currently waiting for a new arrowhead unit.

Could you please let me know the part number for that cover?

And what did they ask for it?

 

[blitz11]

I am not very familiar with the new bikes. Did the old one just have a bronze bushing? Interesting that the casting date shows "14." Generally, this would mean that the casting was made in 2014. Perhaps Rieju modified their stock to replace the bushing with a needle bearing? (Please forgive my ignorance if i am way off base.)

 

[gg3]

They must have an engineer at Reiju !
Old system has no bearings or even simple bronze bushings for the bendix shaft.Notice the new cover has a bush for the pinion shaft as well.Nice.

 

[blitz11]

Huh? Not even a bronze bushing? That's shocking (pun sort of intended given that this is connected to an electrical part.)

Boy, no wonder there are binding/friction issues. I had no idea that they have a shaft running in an aluminum casting.