Tappet nuts

[Wingedwheel]

It sounded scary because you said you found a loose nut that had been possibly crushed by a Cam lobe or did I read that wrong?

 

[DB90]

Gotcha and nope you didn't read it wrong lol. It appears that the nut may have jumped up on the little "fence" between the valve spring area and where the cam is. I think it just barely grabbed the nut, enough to squish it a hair and then spit it out. Unless the valve spring or something on that side did it I'm really not sure what happened, but I can't see any damage to anything aside from the cracked valve spring retainer.

I assumed the valve retainer got cracked from the rocker arm slamming on top of it but I really don't know lol

 

[RC4MAN]

Actually Grade 8 is a US standard and isn't directly applicable to the metric nuts used for the tappets.
Standard metric hardware generally comes in at their grade 8.8, to upgrade I think the next level up is 10.8 or 10.9 then 12.9

 

[gggGary]

Yes the lose nut cracking the "fence" behind the cam is popular, if you're real unlucky it punches through the floor below the cam letting the oil out.

 

[DB90]

Lu

Yes the lose nut cracking the "fence" behind the cam is popular, if you're real unlucky it punches through the floor below the cam letting the oil out.

Luckily neither of those happened!!

 

[JJames]

I erased this reply once cuz (do no harm).
But when snugging nuts (these especially) my last motion is a slight jerk. With threads, tightening, torque there is a thing known as cold welding. We've all experienced it, that slight catch/graunch as the nut gets tight, stops. The feel/sound is small areas of the sliding metal faces micro welding. This is part of what keeps a tight nut in place. Dunno, but I've never had a tappet nut loosen and I don't go gonzo on the wrench.
PS using an offset 6 point wrench here is more than a suggestion. Finish with a slight bump on the wrench.
That is all.

PPS Nichole is a honey.
View attachment 222149

 

[jpdevol]

While we're here: pic of 12mm, 6pt socket with a handle welded on. Mimics the old factory tool NLA. T

humbscrews can be found in kits w/10mm tappet wrenches. Advantage: stays on nut while hands work feeler gauge and thumbscrew, etc..

 

[DB90]

Does ANYONE in this thread have some tappet adjuster nuts? I am having a hell of a time tracking some down

 

[jpdevol]

Yamaha p/n 90170-08173-00 fits other models including power equipment. P/N does indicate it's not a generic 8mm nut (after all this discussion )

one online https://www.ebay.com/p/12021219100

 

[Jim]

There's a Yamaha dealer just south of you. Wouldn't surprise me if they had 'em in stock.
That P/N is used on bikes up through 2017

 

[DB90]

There's a Yamaha dealer just south of you. Wouldn't surprise me if they had 'em in stock.
That P/N is used on bikes up through 2017

Oh cool! What place is it?

 

[Jim]

https://www.powersportsnorthwest.com/

 

[DB90]

https://www.powersportsnorthwest.com/

Oh cool. Yeah I tried them and they had some ridiculous wait time on them. I ended up finding 2 on ebay. They should be here this weekend or Monday

 

[ExSquid]

10.9's and make sure they are the correct size!

 

[DB90]

10.9's and make sure they are the correct size!

Thin and fits a 12mm wrench, yeah? That's what you mean right? Lol

 

[ExSquid]

Thin and fits a 12mm wrench, yeah? That's what you mean right?

Thin and fits a 12mm wrench, yeah? That's what you mean right? Lol

8.8's are like grade 5 in the SAE. 10.9 is like grade 8. I replaced mine with Allen head bolts. The square wrench was gone when I bought the '81.

 

[DB90]

@ExSquid Gotcha. Allen head bolts? What do you mean? Got any pictures of that setup?

 

[nj1639]

If I have tappet adjusters go South for any reason it'll be the incentive to replace them with Virago adjusters......bideing my time.

 

[DB90]

If I have tappet adjusters go South for any reason it'll be the incentive to replace them with Virago adjusters......bideing my time.

Which year of Virago adjusters fit the XS?

 

[nj1639]

Which year of Virago adjusters fit the XS?

There's a thread somewhere in the forum that a search should find.........a lot of my 'memory' resides there lol.