Stripped threads!

Why are so many threads on my wr450 04 made from chocolate!

Both "middle" bolts on the yamaha sump guard are stripped, its now held on by the top and underneath one only. Then this evening, i notice that the rubber I put under the chain guid to prevent the swinger wearing (cheers yamaha) had perished so I renewed it, only tis timeI doubled it up. Then as I did the most rear poxy allen bolt up, (what sort of crap small thread is that), the bastard stripped as well! Must have been to much rubber meaning it would not snug up without striping its threads.

So two things, why the hell do Yamaha insist on this stupic crappy chain guide design, and second, will I be able to drill and tap the swinger to take a more meaty thread? If so what size is the current thread, (its a 3 mil allen head bolt) and what should I go up to.

Seriously kissed off by it, was due to go on a big ride Friday and may not be able to get it fixed in time now! :)

Aluminum threads will pul out of over torqued and used excessivly. Fix, use a helicoil and better yet, replace bolts wityh studs and nuts for the stripped out ones. When tighening bolts in AL, just snug is all you need.

Well fixed it. drilled it out and retaped with a nice long 6mil threaded bolt. Took all the rubber pieces out and used a windscreen sealer (bond) glue stuff to just stick the sodding guide to the swinger, sealed it all round so no crap can get in, and did the studs up.

Let it go off and it sould be good.

Fingers Crossed!!

I vote for using steel nutserts. :)

Lay off the steroids. :)

I too have had some problems with Yamy's in the past but my current WR seams to be holding tight.

For those small bolts a 1/4" drive torque wrench is a must. :)

You'd be surprised how little effort it takes to acheive proper torque on those small fasteners. You can use blue Loctite (Low/medium strenght) if you want to make sure it stays put.

Your over tightning way too much.

I know but I cannot get a 1/4 drive torque wrench anywhwre here in the UK!

Once I stripped them all, I will break it for spares and sell them, The bike wont hold together no more, but it will strip apart easily! :)

it's probably a M4 thread. Due to the fact that the material is thin, you want to keep the thread as fine as possible. The larger the bolt, the coarser the thread. The coarser the thread, the less turns of 'meat' there will be in the thin swingarm wall. I would go M5 if there is enough material left on the swingarm. Also, you may have to modify the caps to suit the larger bolts. If you stripped it, you either over tighterned it or cross threaded it. Remeber, it's only a chain slider.

The swing arm chain buffer slider bolts are real small with no thread wall in the swing arm. I drilled out the tapped holes on top and bottom and put a 1/4" bolt that is 5" long right thru the swing arm to the other hole with a lock nut on the bottom. Now it is easy to replace the chain slider and not have those small stock screws loosen or strip. :)

That sounds like a good idea. :)

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