Ever done a repair you weren't proud of? But it worked?

ChopperCharles

Active Member
I bought a wrecked 1993 CB750 Nighthawk for $500. It had ran up until two weeks ago, when the guy "laid it down" to avoid a car that stopped suddenly. And what that meant was he and the bike slid under the car, and the left engine case got busted by the car's undercarriage. The left engine cover was sheared completely off, along with the mounting bosses and part of the case. The hall sensor was busted and the trigger was sheared off as well.




Charles.
 

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I figured it was a parts bike, but it was in really nice shape. No other damage, and it was a recent runner.... so I took a chance.


First thing I did was replace the hall sensor and the trigger with parts from eBay. Was only about $25 shipped. And... the bike started right up! Spewed oil everywhere because there was no cover, but it started and ran! Shut it down immediately, and got started with what I thought would be a temporary repair.


I got some of that metal putty from the auto parts store. Not JB weld, but the putty that comes in a small tube. I bought four or five tubes of it, and a shitton of Brake Kleen. Sprayed everything down and cleaned up all the oil residue, and then I proceeded to build up new bosses out of this putty. I drilled and tapped the bosses, and then added helicoils. For the missing bit of engine cover, I cut a small piece of aluminum and used this same putty to hold it in place. Then I used a belt sander to sand everything down flat and flush with the original case.


The pics below show two new holes drilled and tapped, and the third one will be drilled after using a new cover as a template.


Charles.
 

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After getting a new cover I located, drilled, and tapped the final hole. Sanded everything down as flush as possible, used a teensy amount of silicone gasket and an OEM ignition cover gasket, and it all sealed up! I put 10k miles on the bike this way, and never had another problem with that engine cover! I was always telling myself if it started leaking or if it failed, I'd find a new motor or at least a new lower engine case... but it never did. I seriously had zero problems with it. Of course, it would never have taken even a mild tip-over without completely re-busting my hack job... but who cares, I had a motorcycle and I had fun.


Here's a pic of the whole bike!


Charles.
 

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I've fixed some JB Weld repairs on bikes I bought that did not work- a spark plug "fix", case holes from broken chains, ground side covers, broken side covers, etc. I'm a huge fan of the Alumiweld low temp welding rod for those fixes. It works really well. I really impressed, though, that your epoxy fix worked. I've argued against them as a permanent, or even long-lasting, fix. But 10k miles is a bunch of miles. During my time in the Navy, the reduction gears off one of our turbines for the port shaft developed a crack in it's case. They tried a host of epoxy fixes to shore it up until a more permanent solution could be found. Absolutely nothing worked to seal it up. The best we got was a much slower oil leak and an EN2 with rags to monitor it.
 
I've tried alumiweld rods, and couldn't get them to work very well at all. Even with oxy-acetylene heat, freshly ground and prepared surface, etc. I had very, very poor results.

I pulled apart a CX500 motor once to find part of the water jacket around the cylinder replaced with JB Weld. The motor was running and the head gasket wasn't leaking. Granted the steel cylinder and the metal ring of the head gasket does most of the sealing there, but still, I was impressed that it held up, especially with the heat cycles of a cylinder head. So I gave it a try here, and surprisingly it worked. As I remember now, two of the holes were made by putting greased bolts in the remainder of the old threads, and packing the putty around them. There was still a significant amount of the original boss left, and original threads helped hold the bolt in place. The final one at the bottom was drilled, tapped, and helicoiled, as there was no part of the original boss left there, so it was necessary to use a helicoil.

There is only oil splash under that cover, not high pressure oil; that is likely why I didn't have any problems.

If I still had the bike today, I'd likely look into permanent repair options. Or maybe I'd just put a case guard on it and continue riding until it failed. I dunno. It's hard to argue with no leaks and no issues for 10k miles.

Charles.
 
nice repair, I've used 2 part epoxy glue to repair a decent sized hole in the bottom corner of an alternator case and it was still there when I sold the bike 10 years later. pissed oil out of every other join in the motor but none out of my repaired bit. win
 
One of my guys hit my rip saw with a forklift and broke a large chunk out of the casting that holds the crank handle to raise and lower it.
The only reasonable option was to JB weld it as it's cast and very thick. Cleaned it well and JB welded it and it's been going strong for many years now with 8hrs/day use.
 
I used bubble gum to keep the condenser wires attached because I got stuck without a soldering iron, worked though. I was just a kid and I left it like that. After I sold the bike the new owner took it to a shop for a tune-up, the mechanic nearly died laughing when he saw it.

It was a friend that bought it and I was terribly ridiculed about it and deservedly so.
 
Few years ago I bought a Sportster off some sketchy chopper dudes. No front brake (because choppers) among a number of other wonky little things. Anyways, I'm bombing down I-35 a few weeks later doing about 90, exit the highway, and on the exit ramp go for some rear brake. Brake pedal basically falls out from under my foot and I realize I have no brakes! So I smash down through the gears to try and slow down, avoiding traffic, and almost blow a red light that just BARELY turned green as I plowed through it, and then slow enough to make it into an empty parking lot off the service road. Turns out the pin that holds the brake pedal to the plunger on the MC had come out somehow. So, on the side of the road and with no other real options, I took the key ring off of my keys and looped it through the pedal and plunger. Voila! Brakes! Anyhow, limped it down the road to a little Mexican tire shop, and through extremely broken Spanish negotiated $5 for a small bolt to get me home safe(r than the keyring).

Words of wisdom: you're not too cool for front brakes! I promise!
 
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