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Discussion Starter #1
The case for my 175 had been damaged at some point in the past. It looks like the chain came off the c.s. sprocket and really caused a ruckus. The boss for that sidecover as well as some of the case was broken off and has been rewelded. It was a decent job but you can see daylight between the two case halves and it looks like a gap to great for hylomar or any other case sealer. It should be welded and machined but I don't have access to either service in a resonable amount of time. Is there a gap that would be too big for JB weld to fill?
bfd
 

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I used JB weld to repair the oil drain boss on my son's XR100. The threads and part of the boss just broke off. I put a universal drain plug with a "piggyback" plug in, and used JB Weld to fill in and seal the 1/4 inch gaps. That was over 5 years/racing seasons ago.
You'll be fine.

FR
 

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You know, Superman saves burning airplanes from crashing. Spiderman swings in to save a falling baby! Wonderwoman, well....you just got to love Wonderwoman. But! A JPweld question is best answered by the King himself....the mighty...the "sting like a butterfly, float like a bee (reverse that)"....we all know him as the Dashing Dom! Al? So says you?

Yeller'
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Ask not what the wanker can do for you, but what you can do for your wanker!
 

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Between case halves? How would you get it to not stick to both sides of the case? I guess you could use wax paper or something...

I had to cut a hole in my RD350 cases in order to fit my large carbs. I filled the hole with JBweld, worked great. But that isn't sealing between the cases.

If you have good crankcase ventilation, the case pressure shouldn't blow out any yamabond/hylomar.
 

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a friend of mine discovered a huge hole ripped by the chain in the back of his engine case. He filled it with jb weld and the bike runs fine now. Golf ball sized hole.

you don't want to jbweld your case halves together because then you will be cutting them apart later.
 

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Discussion Starter #6
A straightedge shows the bottom half is ok, it's just the upper half that needs to be built up. I guess I can put a few hatch marks on the mating surface to give the JB weld something to stick to. The case vents out of the top cover as well as the dip stick so there shouldn't be a lot of case pressure but the gap is too big for something like hylomar.
BFD
 

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do it
. sand it with an agressive grit 36 grit. also you can wipe it with acetone to clean the surface. jbweld it. use wax on the surface you dont want it to stick to.

dude. if i cut my hair will i still be on the team?
 

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JB weld is the shitznitz! I had a helicoil go bad at loudon and I used goop of jb and it actually held all the way after turn 3. Then I heard the awful sound and started to get zapped by the sparkplug which was still attached to the plug wire. Ouch!

I live by JBtheotherone!

Sotomoto

"Dude just connect the dots on the track and you'll be ok"
 

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I think I have a 175 verticle engine (not sloper) in my brothers junk pile. Come get it is you want it--it is still in the remains of the bike. Probably seized up. Of course, you could probably buy one at that junkyard in NH for less than the gas to come to NY.
 

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Discussion Starter #10
Thanks Jack but this is a sloper model.

Matt- if you cut your hair it'll improve our power to weight ratio but cut down on the photo oportunities
Is monkey man getting all wound up about Santa?
bfd
 

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BFD,
Send me a pic of the damage if you can. The countershaft bearing area is under some considerable stress.
The side cover bolt boss is no biggie...seen lots of those broken off. But that big counter shaft bearing has quite a bit of load on it when you launch the bike.
If it's just a matter of sealing then JB weld it on wax paper or something like Rob said...then tape some good sandpaper to a surface plate or something really flat and lap the whole case down a bit..the JB weld should grind down quicker than the aluminum and leave a pretty flat surface.
JohnnyB
 

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so you dont jb weld yer shit together, "fabricate" yerself a type of gasket for lack of a better word out of a plain old milk carton obviously the cardboard type...

t...
 

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Yeah....good idea..the wax inside of a paper milk carton would probably work well.
JB weld settles out quite a bit...might have to build a little "form" to hold it in place while it cures.
JohnnyB
 
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