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HOW TO: DR-Z400 Stator and Starter Clutch LocTite fix

One of the DRZ400’s preventative maintenance areas, the stator and starter clutch fasteners vibrating loose.

This page will address one of the DRZ400’s preventative maintenance areas. Stator and starter clutch fasteners. There has been history of the hex head fasteners that hold the stator to the cover, and the fasteners that hold the starter clutch to the flywheel to vibrate loose. When this happens, the result is a destroyed stator, flywheel and sometimes starter clutch and cover.

The preventative fix is simple, low cost and effective. Basic hand tools, a bottle of thread locker (or two, as I recommend med strength Loctite 242 for the stator bolts and high strength Loctite 271 for the starter clutch bolts. Permatex also makes a commonly available thread locker in Medium and High strength)

First up the stator fasteners.
First problem, why won’t the cover come off when I’ve removed all seven visible bolts? Answer: there’s an eighth bolt hidden inside the starter gear cover and not mentioned in the FAQ. You have to get out the impact screwdriver and take those three soft Phillips head screws out. Don’t try to get them out without the impact tool – you’ll booger the heads for sure.

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Once you remove the starter torque limiter and its cover out this is what you’ll see this

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If the torque limiter doesn’t come out with the cover, just take hold of it and pull it out. Do NOT remove the circlip on the shaft – leave the cluster intact. Another thing to be alert for – there’s a bushing in the center of the cover and another behind the torque limiter (in the cover itself).

Here’s the hidden bolt (red arrow), along with the inner pilot bushing (green arrow) that can drop out and get lost when you turn the stator/cover over. I was fortunate to see it hit the concrete under the bike. The other bushing is in the starter gear cover itself – I don’t know if it will also drop out but you should be aware of it, just in case.

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To gain access to these bolts you have to remove the stator cover. Yes there is supposed to be oil in there, do not panic when you remove the cover and some oil pours out. Highly recommend draining remaining oil when you’re done and side cover is back on,, Best time for an oil change is after you have had the motor open. To otherwise minimize oil loss, start the bike just prior to doing this project. That will move most of the oil into the frame tank. You can also lean the bike over to the right to further minimize oil loss. If you drop in two full quarts or liters when you do an oil change, you really should be fine with what little oil you lose doing this job. The gasket is a metal core; fiber covered and is reusable in almost all cases. The cover will take some pulling to overcome the magnets in the flywheel, and there are two dowel pins used to locate the cover correctly. You must evenly remove the cover so as to not bind it up.

Once the cover is off, remove the fasteners you see in the picture above, clean with some Brake Clean or like solvent, clean the hole the screw goes in to. Place a drop of med strength thread locker on the screw and reinstall. Repeat for all of the fasteners you see in the picture.

Next:  Starter clutch / flywheel fasteners.

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This is an edited pic from the service manual… This picture shows the correct placement of the two shims used with the starter idler gear.
One shim on either side of the circlip. The manual and parts fiche shows one shim on the motor side of the gear.. that is wrong. If placed there, often what you’ll find is the shim broke and in the motor, or stuck to the stator magnates.

These 6 socket hex head fasteners have been the cause for more than one destroyed stator, flywheel and starter clutch. Exactly why they back out or shear is open for discussion. Simple vibration is one reason for sure. Another is, when you stall a DRZ motor and the motor is forced backwards; say while on an incline on your SM or off road while climbing a hill the motor stalls, you’ll hear the “gear winding sound as the motor is actually turned back wards. Shearing these fasteners is a common occurrence on the LTZ (ATV version of the DRZ) the same forces when an ATV spins around backward and the motor gets reversed , are the same forces a DRZ motor sees when stalled and the bike weight forces the motor back for a partial revolution. This is believed to be a proximate cause for the starter clutch fasteners loosening or shearing.

If the 6 socket hex head fasteners are tight and in good shape replacing them is not required. However, if they have come loose, or simply as an upgrade to increase clamp force between the flywheel and starter clutch, you can take this opportunity of having the cover off and fasteners accessible to replace them with grade 10.9 or 12.9 fasteners if available.

Add a drop of High strength Loctite and tighten the stock grade 8.8 fasteners back up to 70 IN LB and your done with this part.

M6 x 16 x 1.0 grade 8.8 are what the OEM specs for this assembly.

NOTE, fellow users have provided info that suggests the OEM fastener is in fact a grade 10.9 from factory.

I respect his opinion as I have always found it to be based on fact and personal experience. I can only assume the OEM has used both grades, as I’m positive the fasteners I’ve replaced in at least one DRZ were not grade 10.9. Truthfully, I never even checked the others I’ve done this fix to assuming if one came this way, that was the standard.. So they may have in fact already been 10.9s in the others.

In that light, replacement of the OEM fasteners is still recommended, so you know you have a good fastener of know condition and grade. Use a 10.9 or 12.9 and follow the recommended torque spec’s for your chosen grade.
You can replace OEM fasteners M6 x 16 x 1.0 in Grade 10.9 or 12.9.

If using these grade fasteners Torque them to:
10.9 – 120 inch pounds (10 ft lb)
12.9 – 144 inch pounds (12 ft lb)

So discussion of the why is open, the fix that seems to stop the issue is to use high strength thread locker on these 6 fasteners. The procedure is the same as above for the stator screws. Remove one at a time, clean, add one drop of thread locker, reinstall.

Resources: Bronco78 at ThumperTalk

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6 Responses

05.17.10

HI NEED HELP, I REMOVED MY STARTER CLUTCH GEAR TO REPLACE MY STATOR ASSEMBLY AND LITTLE DID I KNOW I REMOVED THE CIRCLIP (IDIOT) ANY WAY OF COMPRESSING THE CLUTCH GEAR SPRINGS TO REFIT THE CIRCLIPS. OR DO I NEED TO LOCATE A NEW CLUTCH CLUSTER

05.17.10

Helpful blog, bookmarked the website with hopes to read more!

Very enlightening and beneficial to someone whose been out of the circuit for a long time.

– Kris

05.17.10

Get a snap ring tool to put those circlips back on.

05.17.10

I work for a Suzuki dealer in Australia and have repaired this issue on both SM and E models, our online manuals were updated with a bulletin about the starter clutch bolt issue where they have now dramatically reduced the specified torque setting and stated that a thread locker is now recommended, I’ll find out said specs and post them here asap, can’t recall off the top of my head.

05.17.10

Your Comments i have a eiger 400 4/4 automatic atv i cant figure out how it gets fire to plug i have looked for a stator on it and cant find it im not getting fire to plug i pulled up on a road and turned the key off thats the last time it ran i need help. god bless

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