yukonerdave
Well-Known Member
If you've never had an issue starting your 'Max, count yourself lucky, cause it SUCKS. I gather that there are numerous possible causes (weak charging system, the notorious crimp, cracked coils, poor grounds all around, weak battery), but it seems that sooner or later the starter itself is going to need to get checked out. The unit is sealed tightly enough that as the brushes wear down everything gets covered in dust and the ground connections within the starter start to fail. Rebuilding it is not especially difficult, and it may just get you back on the road.
I'm using an older model 2-brush starter but I assume that the newer 4-brush models suffer from the same problem, and will come apart the same way.
First things first, disconnect the battery (learned this the hard way). Remove the faux cover, the right side scoop, and the radiator cap
We're going to drain the coolant and remove the radiator in order to get easier access to the starter. I'm sure its possible to do it without removing the radiator, but you do need to displace hoses in any case so you're going to want to drain the system anyway. I found that getting the radiator out of the way entirely took an extra 2 minutes, and just helps you to see what you're doing. Start by turning the draincock so the little ball sits in the bottom hole. Then remove the main drain bolt under the water pump. It will pour out fast once you pull it so be prepared. If you haven't changed your coolant in a while this might be an opportunity to flush the system and get some new coolant anyway. I just changed mine, so I will keep it in a clean bucket and reuse it:
The starter is behind the radiator hoses. I removed the side covers on the radiator (two screws on each side), and then removed the bolts holding the radiator to the frame:
Figure out which hose clamps to loosen and pull them off, being prepared to catch more coolant. I caught most of it in the wife's measuring cup (oops), and the rest soaked into her bathroom towel :clapping::
You'll also want to remove the horn. Two bolts on the bottom bracket, and the wires just pull off:
With the horn and hoses out of the way you are ready to remove the starter. It is held on by two bolts (in red), and you can also remove the power cable at this point (in green):
Next part is a little tricky. You can pull the starter towards the right side of the bike to disengage the teeth from the gears. At this point it is going to seem like you need to remove the thermostat to get it out, but with just the right wiggling and manipulation you can work it out without removing anything else:
Alright she's out and ready to to be disassembled. Two long bolts hold the case together - take em out (helps if you have a dog to grab your tools):
Pull the top cap off, and remove the ridged washer and three spacers:
Now you can pull the unit out of the case and set it aside:
The bottom cap will also pull right off. Under it there is a thin plate with the brushes mounted on it. The plate is wired into the main case:
These three tabs are the culprit. The contact three corresponding bumps on the inside of the bottom case, and that is how the power going to the starter is grounded. As they get caked with dust, you lose grounding. Start by removing the brush plate from the case by taking out the screw holding the wire on:
Might as well take the opportunity to inspect your brushes. I had new ones anyway, so I exchanged them. Here's the difference between old and new:
Basically what you want to do now is ensure that you are getting a good solid connection between those tabs and the corresponding bumps on the interior of the bottom case. I used a dremel to take them down to bare metal, and also bent the tabs slightly so they would be pressing against the bumps when I reassembled everything:
That's about it. I know others have actually soldered a wire directly onto the brush plate and then drilled a hole in the bottom case to attach the ground wire to a small screw. I'm hoping that what I've done will be enough but if I need to do this again I'll consider doing that. I used brake cleaner and the wife's toothbrush to clean all the dust off of everything. Putting the unit back into the case is a little tricky - just push the brushes back against their springs to allow it to sit properly. I imagine this is even more tricky with the 4-brush models:
Note the alignment marks on both the top and bottom cases to line them up correctly:
Also apply a little grease to the bearings on either end before re-assembling. I believe that there is a rebuild kit with new brushes, washers, spacers, and O-rings - check all of those before reusing them. Once it is back together, make sure it spins before reinstalling it on the bike. Just hold it in a clamp, run a jumper cable from the negative terminal of your battery to the starter case, and run the positive to the terminal bolt (I used a jumpstarter instead):
Assuming it spins well, it goes back in the way it came. Make sure all the radiator hoses are attached and clamped before refilling the coolant. Also take the opportunity to inspect your starter wire - I removed mine and upgraded to a thicker one. At the very least, take a wire brush to the connection and the terminal on the starter. That's it - fire her up and listen to her growl!
***EDIT - Starts like a F***in CHAMP now, both cold and hot! This is a great fix if you've got starting problems***
I'm using an older model 2-brush starter but I assume that the newer 4-brush models suffer from the same problem, and will come apart the same way.
First things first, disconnect the battery (learned this the hard way). Remove the faux cover, the right side scoop, and the radiator cap
We're going to drain the coolant and remove the radiator in order to get easier access to the starter. I'm sure its possible to do it without removing the radiator, but you do need to displace hoses in any case so you're going to want to drain the system anyway. I found that getting the radiator out of the way entirely took an extra 2 minutes, and just helps you to see what you're doing. Start by turning the draincock so the little ball sits in the bottom hole. Then remove the main drain bolt under the water pump. It will pour out fast once you pull it so be prepared. If you haven't changed your coolant in a while this might be an opportunity to flush the system and get some new coolant anyway. I just changed mine, so I will keep it in a clean bucket and reuse it:
The starter is behind the radiator hoses. I removed the side covers on the radiator (two screws on each side), and then removed the bolts holding the radiator to the frame:
Figure out which hose clamps to loosen and pull them off, being prepared to catch more coolant. I caught most of it in the wife's measuring cup (oops), and the rest soaked into her bathroom towel :clapping::
You'll also want to remove the horn. Two bolts on the bottom bracket, and the wires just pull off:
With the horn and hoses out of the way you are ready to remove the starter. It is held on by two bolts (in red), and you can also remove the power cable at this point (in green):
Next part is a little tricky. You can pull the starter towards the right side of the bike to disengage the teeth from the gears. At this point it is going to seem like you need to remove the thermostat to get it out, but with just the right wiggling and manipulation you can work it out without removing anything else:
Alright she's out and ready to to be disassembled. Two long bolts hold the case together - take em out (helps if you have a dog to grab your tools):
Pull the top cap off, and remove the ridged washer and three spacers:
Now you can pull the unit out of the case and set it aside:
The bottom cap will also pull right off. Under it there is a thin plate with the brushes mounted on it. The plate is wired into the main case:
These three tabs are the culprit. The contact three corresponding bumps on the inside of the bottom case, and that is how the power going to the starter is grounded. As they get caked with dust, you lose grounding. Start by removing the brush plate from the case by taking out the screw holding the wire on:
Might as well take the opportunity to inspect your brushes. I had new ones anyway, so I exchanged them. Here's the difference between old and new:
Basically what you want to do now is ensure that you are getting a good solid connection between those tabs and the corresponding bumps on the interior of the bottom case. I used a dremel to take them down to bare metal, and also bent the tabs slightly so they would be pressing against the bumps when I reassembled everything:
That's about it. I know others have actually soldered a wire directly onto the brush plate and then drilled a hole in the bottom case to attach the ground wire to a small screw. I'm hoping that what I've done will be enough but if I need to do this again I'll consider doing that. I used brake cleaner and the wife's toothbrush to clean all the dust off of everything. Putting the unit back into the case is a little tricky - just push the brushes back against their springs to allow it to sit properly. I imagine this is even more tricky with the 4-brush models:
Note the alignment marks on both the top and bottom cases to line them up correctly:
Also apply a little grease to the bearings on either end before re-assembling. I believe that there is a rebuild kit with new brushes, washers, spacers, and O-rings - check all of those before reusing them. Once it is back together, make sure it spins before reinstalling it on the bike. Just hold it in a clamp, run a jumper cable from the negative terminal of your battery to the starter case, and run the positive to the terminal bolt (I used a jumpstarter instead):
Assuming it spins well, it goes back in the way it came. Make sure all the radiator hoses are attached and clamped before refilling the coolant. Also take the opportunity to inspect your starter wire - I removed mine and upgraded to a thicker one. At the very least, take a wire brush to the connection and the terminal on the starter. That's it - fire her up and listen to her growl!
***EDIT - Starts like a F***in CHAMP now, both cold and hot! This is a great fix if you've got starting problems***
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