Argo's Starter Clutch Replacement

[Pardee]

Having issues with your faulty starter clutch?

Did you hear about Argo Raudvee's hard work to find a fix for us TX750 owners?

The original thread can be found at the Adventure Rider Forum - Yamaha TX750 starter clutch mod!! OH YA!!

These replacement starter clutches are available now.

[Pardee]

I received my starter clutch replacement from Argo last week.

Install was easy, and I'm glad I don't have to hear the starter clutch chatter behind my left side case cover anymore.

[argo1974]

I just tested installing my starter clutch with MINIMAL EQUIPMENT consisting mainly of bench drill and few hand tools.

1) Here a picture of the parts, sprag taken out of the outer ring. In case the outer ring won't sit flat on rotor's face, flatten the grooves caused by 3 rollers and/or 2 pins of the stock starter clutch.


2) Align the outer ring with any screw hole between any magnetic poles on the rotor. Mark the position.


3) Fix the rotor on bench drill, e.g. using a screw through rotor's center hole. Fix the outer ring, e.g. using duct tape. Or, if you have more sophisticated equipment, clamp the rotor and outer ring down together. Use 8mm drill bit ONLY TO DIMPLE DOWN AND MARK THE FIRST HOLE.


4) Hole position marked using 8mm drill bit.


5) Hole position marked with outer ring removed.


6) Drill the first hole using 6.8mm drill bit. Be careful while drill bit brakes through and do not touch magnetic pole of the opposite side. Drill bit will brake immidiately!
Clamp down the rotor while drilling!


7) Cut M8x1.25 thread. To have the the thread cut started absolutely straight, fit the tap to chuck of the bench drill and turn first few revolutions by hand.


8) Fix outer ring using one screw.


9) Dimple down and mark another 5 holes using 8mm drill bit.


10) Positions marked for another 5 holes with outer ring removed.


11) Drill & tap another 5 holes with 6.8mm and M8x1.25mm respectively. If needed, slightly chamfer the threaded holes using 11.5mm drill bit.


12) Test fit starter clutch unit. If OK, clean & degrease significant areas. Use Loctite blue on screws and tighten them down evenly (Torx T30). 


13) Chamfer the starter gear for easier installation if needed.

Order info: final price $110 + shipping (most countries, e.g. USA, is $10). I can accept Paypal and/or bank transfer. Please order through email [e-mail]

[roundporch]

Thanks Argo!  Another successful install.  I was able to do this without a drill press, not recommended but I used a 9mm deep socket and some "spacers" to make sure the bit didn't dive too far and hit the pole.

See my post in wanted section, my Starter Sprocket is pretty beat up think it will be fine but rather use replacement if I can find one

[aj]

hi,

is argo still selling the starter clutch......written him an email but haven't heard back

[si144r]

Ive installed my Argo starter clutch modification at home in the garage , very simple and easy to do.
Brilliant piece of engineering , my bike started first press of the starter button , amazing

[minnesota750]

I installed mine over the Winter - works great! I suggest all TX owners upgrade.

[bruno55]

Hello,
how will I buy this "ARGO "? which is the address for the contact?

I would get these pieces to make the change.

Thank you
BRUNO 

[bruno55]

Hello and happy new year,
How I buy this "ARGO" ??

[argo1974]

My email is still [e-mail]

[deathbynissan55]

I just bought one of these.
No fault of Argo's but make sure you request package tracking number. It took much longer than he expected it to get to the states from his location in Europe.

[deathbynissan55]

Also, it doesn't say above, but if it wasn't obvious, you should reuse that little shim washer that goes between the original starter gear and the rotor. It should sit between the rotor and the newly added sprag mechanism (except have it lined up with the hole prior to assembly haha).




****UPDATE ON ASSEMBLY ONTO BIKE ONCE MACHINING IS COMPLETE*****

The way i did it, after chamfering the starter gear more than 1mm, is as follows:
1) Clean and install the 2 starter gear and chain assembly onto crank and starter shaft.
2) Put some moly grease on the tapered part of the crank.
3) Rotate crank using kick pedal or something so woodruff key slot is pointing up and place woodruff key in contoured slot on crank.
4) Lubricate shim with assembly lube or whatever engine oil you use and place shim under sprag mechanism as shown in picture above.
5) *THIS STEP IS KEY* Slide shim so that key slot is totally visible, then try to slide rotor/new sprag clutch/shim assembly with key slot pointed up and try to catch the key with the rotor while shoving it onto the crank.  You may have to rotate it a little when place on there.  You should be able to feel a distinct difference between when you have it slotted correctly versus if you just slid the woodruff out of its slot on accident and jammed it between the sprag and the starter gear.
6) Once you get slotted correctly, partially thread the crank bolt with washers on, so that it doesnt allow it to fall out of the slot while you're doing the next step.
7) You can do it 1 of 2 ways, you'll need 2 people to do either way.  1 way is put a rag on your hand put pressure on the outer lip of the rotor - while doing this, have someone use the kick pedal SLOWLY to make the crank rotate which will turn the correctly slotted rotor (if it doesnt turn the rotor while he's kick, then you probably didnt slot the key correctly so remove and try again).  This should allow you chamfered edge of your starter clutch catch on some of the teeth.  Give it a wiggle while your friend is rotating the crank and hopefully it should seat

The other way is to use a rubber mallet or soft hammer and while your friend is rotating the crank, do some light taps in a criss-cross pattern on the outer edge of the rotor to get the starter gear to slip into the sprag. (when doing it this way, its important to make sure that crank bolt is applying pressure to the rotor so that it doesnt come out of the slot).

8) once its fully seated, put light amount of lube on the crank bolt and use both the spring and flat washer and install the bolt.  Torque down to 35 ft-lbs.

SHOULD BE ALL GOOD TO GO AFTER THAT!!!!!
Hopefully my explanation helps someone, i struggled with this for days before i just decided to chamfer the starter gear more than it says in the picture above.  As long as the chamfer is even and you dont create any sharp edges on the face of the starter gear or on the contact surface where the sprag engages, it should be fine.

[deathbynissan55]

Just an update, Argo said more than 1mm chamfer on starter gear is ok. It makes it WAAAAAYYYY more easy when you put a bigger chamfer on there. Don't make it so slides in and out super easy, just make it so you have to struggle only a little bit haha. I just used a bench grinder and carefully rotated the starter clutch, went from bike to bench grinder a couple times - make sure to grind away lightly in steps to avoid messing it up. Make sure to lubricate the tapered part of the crank with moly grease before assembling total starter clutch/rotor assembly.

Also, apparently it was in one of those service notices from back then, but the torque spec on the bolt holding the rotor/starter clutch onto the crank is 35 ft-lbs lubricated.

I did not look in the service letter section of my factory service manual though, so it might have been there.

[deathbynissan55]

Oh and just remembered, the correct way to install that left case cover gasket is to feed the electrical harness through it.....Screw that hahahaha

Instead of doing that, what i did was cut through the gasket at the top right corner with an exacto knife (or just something super thin and super sharp), put the AC Generator harness inside the opening on the top right of gasket, then once you get the inner cover on (which is the important one because it will see oil) put a very small amount of Grey RTV over the slit you cut into the gasket. Then follow your directions for whatever Grey RTV (gasketmaker) you get for assembling the piece to set the RTV correctly.

[scrambler]

FYI, This was my solution for chamfering, had to grind off quite a bit.