Heavy Duty Starter Clutch

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+1 to what Max Midnight said. The starter will just draw what it needs. Depending on load.You can have not enough,but never too much battery capacity.
Steve-o
 
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I would have thought that the battery would only supply what the starter wanted?

Mr Sufidancer, did you replace all of the components in the starter clutch assembly i.e. #7 on the parts fische?
Alternatively, have you used silicon sealer rather than a gasket as this can cause the assembly to bind.
Hello, I did replace the referenced parts. But I did not use a gasket. I used red permatex. The last time I replaced my starter clutch I sheared off my crank woodruff key and I did not use a gasket then. Maybe that is my problem. I may be getting a bind. I am going to have to get back into it and this time use a gasket. I am also seriously thinking about spot mig welding the allen bolts. I hope this Heavy Duty starter clutch is heavy duty. It just pisses me off that this Yamaha starter clutch is such a bogus design. Thanks for the ideas.
 
The stator cover REQUIRES a gasket to prevent the step up gears from binding. PCW uses large headed allens that JUST barely fill the openings of the starter clutch then they weld the ends of the bolts to the flywheel.
 
Mr. Midnight, please supply another link, the first one didn't connect for me, thanks.

ClickHandler.ashx


Never-mind, I tried again, and this one opened the doc.

You aren't the first! Read this.
 
+1 to what Max Midnight said. The starter will just draw what it needs. Depending on load.You can have not enough,but never too much battery capacity.
Steve-o

Yes, and no.

Series wound or permanent magnet DC motors have an enormous current requirement initially. You are assuming that the battery can maintain 12v when the starter is engaged, it cannot.

The starter will draw what it needs, but what it gets depends on the resistance of the wiring and the internal resistance of the battery. The initial inrush of current will be higher when the resistance is lower. A bigger battery has lower internal resistance.

Put another way, no battery and wiring combination will be able to maintain 12v at the starter terminals when the starter is energized, the current flow is just too high. If you put a scope on the battery when the starter is engaged, you would see a momentary dip in voltage to 6 or 8 volts or even lower. The larger the battery the less the voltage will drop resulting in more current through the starter. This will give the starter more torque, especially initial torque.

That may or may not make the starter clutches fail more often. I simply offered it as a possibility.
 
Yes, and no.

Series wound or permanent magnet DC motors have an enormous current requirement initially. You are assuming that the battery can maintain 12v when the starter is engaged, it cannot.

The starter will draw what it needs, but what it gets depends on the resistance of the wiring and the internal resistance of the battery. The initial inrush of current will be higher when the resistance is lower. A bigger battery has lower internal resistance.

Put another way, no battery and wiring combination will be able to maintain 12v at the starter terminals when the starter is energized, the current flow is just too high. If you put a scope on the battery when the starter is engaged, you would see a momentary dip in voltage to 6 or 8 volts or even lower. The larger the battery the less the voltage will drop resulting in more current through the starter. This will give the starter more torque, especially initial torque.

That may or may not make the starter clutches fail more often. I simply offered it as a possibility.

Well I do appreciate all responses. And am going to unzip this bike today and have a looky-lou. I pray I do not encounter any buggered up gears or such.
I am having Yamaha cut me a gasket today as well. I will report my findings.
It does make sense the more torque that sucker spins the more wear. Not enough and it shits itself and to much it can shit itself. GREAT.
 
Yes, and no.

Series wound or permanent magnet DC motors have an enormous current requirement initially. You are assuming that the battery can maintain 12v when the starter is engaged, it cannot.

The starter will draw what it needs, but what it gets depends on the resistance of the wiring and the internal resistance of the battery. The initial inrush of current will be higher when the resistance is lower. A bigger battery has lower internal resistance.

Put another way, no battery and wiring combination will be able to maintain 12v at the starter terminals when the starter is energized, the current flow is just too high. If you put a scope on the battery when the starter is engaged, you would see a momentary dip in voltage to 6 or 8 volts or even lower. The larger the battery the less the voltage will drop resulting in more current through the starter. This will give the starter more torque, especially initial torque.

That may or may not make the starter clutches fail more often. I simply offered it as a possibility.

10.5 volt minimum, while cranking. Assuming nothing. We're talking current not voltage. Of course I'm not speaking for Maxmidnight, but I'd bet he's saying yes.
 
They are related. The bigger battery will be able to maintain a higher voltage so there will be more current with a given load, in this case, the starter. More current means more torque.
 
Tossed my Shorie, and wired 5 monsters in parallel. Dam, the torque is incredible. But this trailer I had to buy to tow them around is a PIA.
 
Yes, and no.

Series wound or permanent magnet DC motors have an enormous current requirement initially. You are assuming that the battery can maintain 12v when the starter is engaged, it cannot.

The starter will draw what it needs, but what it gets depends on the resistance of the wiring and the internal resistance of the battery. The initial inrush of current will be higher when the resistance is lower. A bigger battery has lower internal resistance.

Put another way, no battery and wiring combination will be able to maintain 12v at the starter terminals when the starter is energized, the current flow is just too high. If you put a scope on the battery when the starter is engaged, you would see a momentary dip in voltage to 6 or 8 volts or even lower. The larger the battery the less the voltage will drop resulting in more current through the starter. This will give the starter more torque, especially initial torque.

That may or may not make the starter clutches fail more often. I simply offered it as a possibility.
I do not agree entirely. The bigger the battery the higher the CCAs or for layman the cranking power which in this case talking electronically the current. The torque rating for the starter cannot be improved by means of using a truck sized 12v battery. The starter draws what it needs to achieve that torque so as long as the battery and wires can deliver the flow of current requested. That's why a weak battery may not be able to crank the engine as current is not enough. A battery can read 12v and still may be damaged by not being able to deliver rated CCAs. The drop in voltage while cranking is a consequence of the rush of current to the user. Still it should not drop below mid 10s or else ignition would fail by causing misfire and killing engine. Usually a battery that reads 12v but drops below that number will not be able to crank the engine as the CCAS will be lower than its rating due to damage to the cells.
 
Whilst the motor will only take what it wants Mr 1FK00 make a reasonable point.

We have not considered that the OE battery may not be able to provide what the motor could use during the initial rotations of its armature.
With a fully charged battery this isn't an issue.
With a larger capacity battery the motor will take more of what is available.

The unknown factor is a) how much extra torque the battery that Mr Sufidancer fitted gives and b) would that difference have any effect on the durability of the starter clutch. :confused2:
Higher capacity batteries have been used before without ill effect so I suspect it isn't an issue.

More relevant in this case is the omission of the gasket.

Steve - have you considered swapping you five monster with an array of Lithium Nickel Cobalt Aluminum Oxide (LiNiCoAlO2) batteries? With over 600% higher specific energy than a lead acid battery they should keep your starter spinning without the weight penalty! :eusa_dance:
 
Well to follow-up: I got back into the Stater clutch and did not find any damage to the starter clutch. But I did notice the 3 large allens seemed to be slightly buggered on the end threads. So It may have been slipping.

Rather than take any chances I replace the whole starter clutch with a Ebay special that came with replacement Allens screws.

I was sure to coat them with blue loctite and torgued them as hard as I could. I then took a chisel and peaned them all . New gaskets and a prayer. VaROoooommMM! started right up and no leaks. At this rate I give my new starter clutch a month....that seems to be all they last. Maybe I should jettison this bike before this starter clutch goes out. Kidding kidding. But if this one shits the bed I will be paying the 79 bucks for the super duty one.
 
Use Red Loctite 271 instead of the blue stuff to lock those Allens down. It requires 500 degrees Fahrenheit to loosen.
 
Zeus is dead on, Red Loctite is what is recommended for the starter clutch bolts in the Yamaha Service manual.
Blue Loctite won't cut it for the starter clutch bolts.
 
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