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227 Posts
Discussion Starter #1 (Edited)
Hi fellow riders.
Recently I was facing some issues with my bike, even with a full charged new battery the bike was having starting issues.
If the bike was sitting for a week I could see it was facing starting issues, after firing the dashboard was turned off for a second and the start was difficult like the starter was drawing to much power or something.
I did some tests, I put 2 good batteries parallel and I put a Multimeter to the battery.
Fired up a lot of times and I noticed some times the Volt Drain was 1.5v to 2v(from 12.8v to 11v eg) and the bike was starting immediately and some other times the Volts were draining to much, way down to 8v and the bike was struggling to start.
Did some search in here and the Starter was the first thing to blame.
My bike has 61.000Kil, so I figure out the maintenance and inspection of the starter was inevitable.
Now pulling out the starter is a pain in the ass job to do. After checking some Videos I figured there are 2 ways to do it.
1. First by Removing the thermostat
2. Second by removing the injectors.

The first way is the easiest because you don't have to remove many parts, but it will give you a hard time to reach the starter motor, especially the 2nd screw took me about an hour.
The second way is much more pain in the ass as you have to remove the injectors, but after the kit is gone it'll be very easy to pull out/in the Starter Motor.

In my case I went with the first option to remove the thermostat because it had a small leaκ from the thermostat gasket(o-ring), so I had to repair this too.
The first thing to do is to remove the Gas Tank and to disconnect the pipes.
Second remove the air filter box.
Third disconnect the pipes and remove the thermostat.
After that you will have to disconnect some other pipes and after you raise the heat protective cover you will see the Starter Motor.




Ok, now that the starter is out first thing to do is to mark the sides with a marker because you don't want to assemble it the wrong way and not spinning clock wise, witch eventually make the bike not start and you'll have to go all the prοsidure again from the start. (Epic Fail).


Here is what i find.




Well, the brushes seemed ok but definitely the hole thing needs cleaning.


Used some soft sand paper on the brushes to clean them, never use a sand paper on the armature
surface, just clean it with a soft cloth.
Το be continued....

227 Posts
Discussion Starter #2 (Edited)
I did a very exhaustive cleaning just to be sure there where no oil residues left.






Ok, now for the re assemble you will have to put the brushes facing the right way as I show in the picture below...Very important step.

After that, you will have to place the armature first, it's a little tricky because you must pull the brushes back to fit in.
After that place the magnet cover, be sure to much the markers we put before the disassembly(++,--).
With one hand you must push down the armature and with the other place the magnet cover, be carefull because the magnets are strong and may pull off the armature from the brushes, that's why you have to push the alternator with the one hand down.

After that a polish will take place...


Well after the maintenance did some test with a 12v battery, I swear the sound of the starter motor wasn't so loud and for sure it seems to sniping with more power. After a reasearch on the net some guys says that the starter must drain at least 1.5v 2.0v from the battery. So now mine seems ok.
Did a video here

Next step is to find and ampere meter to test it, before replace it on the bike.
To be continued.....

227 Posts
Discussion Starter #5
Ok guys, the AD/DC current tool has arrived and make the test after the Starter Motor maintenance.
I find some Videos on youtube and some guys say when the starter is off the bike it should draw 50-60amps, and when it's one the engine approximately 200-250Amps DC.
I think I'm ok.
Only wish I had the AC/DC tool earlier, to measure the Starter before maintenance, but I'm pretty sure it spins with much more power now.

An R1 kinda day!
2015 Yamaha YZF R1 Raven Edition
738 Posts
Good write up, and I thank you for that.

227 Posts
Discussion Starter #7
Ok guys, I think I just solve my bikes hard starting issues.
After Starter Motor maintenance it's time to put the starter in place...




from the sides if you have removed the chain tensioner and the refrigerator pipes there is access to the screws, especially the inner one which from above is very difficult and will overwhelm you if you choose to not remove the throttle bodies.

Ok and here we are after the installation, the starter motor spins like brand new and starts the bike imminently. The DC Current is measured approximately 140 amperes and the volt drop from the battery is at least 2volts. I remind you that even with 2 parallel 12v batteries the bike was having hard time to start and the volts dropped to 8v giving a hard time to the electrical system and the battery.
Bike now fires up like brand new!

14 Posts
Fantastic write up, thank you! I have the same year bike and was having the EXACT same issue starting about 3 months ago till currently lol. Did exactly what you did and pulled starter (actually not a terrible job IF you have a long 12in Allen wrench extension bar to get those FN throttle body screws out), cleaned it thoroughly...it actually wasn't bad at all and reassembled. Started up fine for first few rides then went back to seemingly shorting out even with brand new battery and fully charged. Sometimes it starts right up no prob...other times it cranks and I hear the juice just being sucked straight out of the battery and in 2 attempts the battery is dead and needs to recharge for another few hours. I'm lost and going to assess the whole charging system one more time before I take it into a shop and hopefully have them fully diagnose it definitively.
Is yours still running and starting strong or has the symptoms started to return? Thanks in advance.

227 Posts
Discussion Starter #9
Yes I have no problem since then, my bike starts right up every time, already did 2000 km after the maintenance going to work day after day with no issue. And I use a 30$ cheap battery, too lazy to put a second better quality I have. :p
I would use a second parallel battery and test it before do anything else to see how it performs, to see if it struggles even with 2 parallel 12v batteries or it fires up strong, or find an AC/DC tool to measure the DC Current the Starter pulls from the battery.
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