Meatball Mechanic; Valve cover stripped stud hole repair.

Ahhhh....2013.

That was before my return to the XS650 fold and during the period when I was fending off grubby, unshaven boyfriends on the front lawn.....

....the bootless and unhorsed.
 
June 2013 XJWMX Yes this stud is the most likely one to strip out, not much depth there.
I've also noticed that it seems to be that one. From what I can gather they used three studs of one length and six of another. That tells you they preferred a longer length and would have used it everywhere if there was room.
 
The lower stud hole on my bike's front right cover is stripped. XJWMX commented that a helicoil fix is better than a reducer stud.

Any other arguments one way or the other on fixing this stripped hole?
 
Helicoils do indeed work well if they're installed correctly (and that isn't too difficult)..

In fact, some engines come from the factory with Helicoil inserts installed in critical holes like spark plugs etc.

Pete
 
That's right. After I did this I learned the normal way to strenghten somthing like that at the factory is to helicoil it. So...the reducer is a lot of work and it's non-standard and nothing special to be gained. You probably need all three done really, top two for prevention, so the standard way starts to really seem like the way to go then.
 
Some folks swear by Time-serts, an alternative to helicoils, but I have successfully used the latter.

http://www.timesert.com/

When drilling out the hole, with the proper size drill bit, it helps to use the re-attached cover as a guide to help keep your drill bit centered and at the proper angle.
There are a number of threads on this topic here at this site.
It is well worth studying up on this procedure. As Pete stated, there are some important variables that can lead to serious failure/damage to your head.
Hope your repair goes well.
 
Last edited:
Or a piece of plate steel for the guide with the same hole drilled though it would be tighter. You can use masking tape on the bit as a depth guide. But if I'd never done one before I would let a machine shop do it and try to watch. Maybe do the other two yourself, if you're handy that way.
 
Thanks guys

xjwmx - I will take your advice and get a shop to do it. I just spent an hour and a half drilling and tapping a chain tensioner and still didn’t get the hole straight.
 
The lower RHfront bolt is the mostly likely one to strip. When I went looking I found the hole is shortchanged by proximity to the exhaust port. Ie the factory scrimped on hole depth so the stud isn't sticking into the port. Incidentally I think the lower LH front stub hole was an issue on the 70-71 motors, I have at least one stripped on my early engines. The 4 bolt cover in 72 let Yamaha correct that design flaw on the left. So IMHO the less material you remove the better when messing with that hole. Guess whatever you do be real careful not to go any deeper. Yeah my special stud is "special" but I'm like that. If the hole isn't really buggered, I'd be tempted to find a 6.3mm stud jb-weld it in place, use a nice fat new o-ring ;) be real careful tightening the nut and call it done. With a good oring you can do most of your tension with two nuts the third can be just a bit more than taken up. Use the valve cover and a purpose made drill sleeve or a lash up a sleeve from whatever's handy at home or the hardware store bins. It's aluminum and you don't need to go much bigger. XJ's steel plate would be OK if the valve gear wasn't in the way but it's a lot of work to make.
 
Last edited:
If the hole isn't really buggered, I'd be tempted to find a 6.3mm stud jb-weld it in place
But Jeez,,,that still isn't the right way and you know it. Was yo mamma scared by a helicoil? I do remember some kind of coil or other that was scaring women.
 
But Jeez,,,that still isn't the right way and you know it. Was yo mamma scared by a helicoil? I do remember some kind of coil or other that was scaring women.
I tend towards minimalism. Dentist wanted to do an expensive project on a rear molar I said pull it. How about red loctite instead of jbweld.? note the 6.3mm I think the reason this size exists is to "fix" slightly stripped 6mm threads.
 
Thanks guys

xjwmx - I will take your advice and get a shop to do it. I just spent an hour and a half drilling and tapping a chain tensioner and still didn’t get the hole straight.
Peter,

Keep in mind that getting a shop to do it doesn't guarantee that it will be done correctly.
Robert Pirsig reminded us of this in his book Zen and The Art of Motorcycle Maintenance. One of the early chapters.
The preferable alternative, in my opinion, is to read up on the procedure, take your time, and do it yourself with the support of this website.
.
.
 
Last edited:
Comment on "trivial" projects and shops, guess who will get assigned to do your minor fix?
 
Comment on "trivial" projects and shops, guess who will get assigned to do your minor fix?
He'll need to be bailed out before he can start the job.

sean-penn.jpg
 
You could just tap the hole for a 1/4" X 20 thread and screw a 1/4 inch stud in the hole. No drilling required, round up a plated 1/4 inch acorn nut to go on top and it looks almost the same.
 
How about red loctite instead of jbweld.?
If it wasn't stripped then I'd definitely use red or even jb as a preventative to keep it from turning and subsequently stripping. But the one in question is already stripped.
 
Robert Pirsig reminded us of this
Of what? :) The thing I remember is You're working on a motorcycle called yourself, or something like that. That is, will you measure once and cut twice. At least with Sean Peen if he fucks up you get a new head :) That's a pretty big recommendation.
 
Pirsig reminded us ........

From Chapter One:
I shrugged and was as puzzled as he was, and stood there with the cars whizzing by, just staring. The engine was so hot the air around
it shimmered and we could feel the heat radiate. When I put a wet finger on it, it sizzled like a hot iron and we rode home, slowly, with
a new sound, a slap that meant the pistons no longer fit and an overhaul was needed.

I took this machine into a shop because I thought it wasn't important enough to justify getting into myself, having to learn all the
complicated details and maybe having to order parts and special tools and all that time-dragging stuff when I could get someone else to
do it in less time.. .sort of John's attitude.

The shop was a different scene from the ones I remembered. The mechanics, who had once all seemed like ancient veterans, now
looked like children. A radio was going full blast and they were clowning around and talking and seemed not to notice me. When one
of them finally came over he barely listened to the piston slap before saying, "Oh yeah. Tappets."

Tappets? I should have known then what was coming.

Two weeks later I paid their bill for 140 dollars, rode the cycle carefully at varying low speeds to wear it in and then after one thousand
miles opened it up. At about seventy-five it seized again and freed at thirty, the same as before. When I brought it back they accused
me of not breaking it in properly, but after much argument agreed to look into it. They overhauled it again and this time took it out
themselves for a high-speed road test.

It seized on them this time.

After the third overhaul two months later they replaced the cylinders, put in oversize main carburetor jets, retarded the timing to make
it run as coolly as possible and told me, "Don't run it fast."

It was covered with grease and did not start. I found the plugs were disconnected, connected them and started it, and now there really
was a tappet noise. They hadn't adjusted them. I pointed this out and the kid came with an open-end adjustable wrench, set wrong, and
swiftly rounded both of the sheet aluminum tappet covers, mining both of them.

"I hope we've got some more of those in stock," he said.

I nodded.

He brought out a hammer and cold chisel and started to pound them loose. The chisel punched through the aluminum cover and I
could see he was pounding the chisel right into the engine head. On the next blow he missed the chisel completely and struck the head
with the hammer, breaking off a portion of two of the cooling fins.

"Just stop," I said politely, feeling this was a bad dream.

"Just give me some new covers and I'll take it the way it is."
.
.
Full text of the book:
https://archive.org/stream/ZenAndTheArtOfMotorcycleRepair-RobertPirsig/zen-motorcycle_djvu.txt

.
 
Last edited:
Back
Top