Total bummer - Broken engine mounting stud

S

Standard Issue

Guest
What a drag!

I'm out on my motored bike, havin a freewheeling good time when
all of the sudden, I feel the motor give way and start to vibrate in
an alarming fashion. Upon inspection, it turned out that the long stud
in the rear had broken off. I found it on the road, and wouldn't you
know it, it broke in about the worst place it could have, right about
1 millimeter below flush on the casting.

So I took the whole thine apart, drilled it and extracted the stud with
an EZ-out. Fortunately that went smoothly.

Now to find some replacement studs, and I'll be back in business.

I have to say, I am a little dissapointed that a stud broke off after only
about 5-6 hours of runtime. Not too broke up about it though...it is just
a cheap chinese bike engine. I expect a little bit of crappyness...kind of
comes with the territory.

Has anyone else had a similar problem, and if so, where were you
able to locally procure some replacements?

standard issue
 
I don't know exactly what you are talking about, but I know that the local ACE Hardware always has any and all metric threaded hardware i've ever needed. Go easy with the wrench, don't torque that cheap Chineese junk too tightly. Loc-tite everything! Vibrations will shake everything lose but if you go too tight you end up with broken bolts. Loc-Tite is your friend.

To all the other hardware stores besides ACE that do not carry anything Metric I say, "Go pound sand, mu^&^$@#@($"!!
 
Standard Issue said:
What a drag!

I'm out on my motored bike, havin a freewheeling good time when
all of the sudden, I feel the motor give way and start to vibrate in
an alarming fashion. Upon inspection, it turned out that the long stud
in the rear had broken off. I found it on the road, and wouldn't you
know it, it broke in about the worst place it could have, right about
1 millimeter below flush on the casting.

So I took the whole thine apart, drilled it and extracted the stud with
an EZ-out. Fortunately that went smoothly.

Now to find some replacement studs, and I'll be back in business.

I have to say, I am a little dissapointed that a stud broke off after only
about 5-6 hours of runtime. Not too broke up about it though...it is just
a cheap chinese bike engine. I expect a little bit of crappyness...kind of
comes with the territory.

Has anyone else had a similar problem, and if so, where were you
able to locally procure some replacements?

standard issue

samething happened to me in the first hour was a big bummer.

Had to order screws from thatsdax.com

but later went to theisens and they have 6mm studs but its a bolt, works good none the less.
 
This just happened to me on my way to work! I was about 2 miles from work with nothing but hill in front of me. I herd a loud pop, then the motor starting shaking violently. :eek: I immediately stopped on the side of the road, shut the motor off and noticed that I lost one of the mounting studs on the back where the bracket attaches to the seat post part of the frame. I was able to use the motor sparingly as I peddled the rest of the way to work. Thank goodness for peddles. I can't tell how bad the damage is. I don't know if it snapped off or if it stripped the threads and destroyed the casting. I will find out soon enough. The Mrs. has to come and pick me up from work. What a drag.
 
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the 10mm combination wrench is your best friend!!

always carry a 10mm wrench, & check mounts, intake, & exhaust every day, especially if you're a commuter 8)
 
I already carry every tool I could possibly need. Or at least so I thought until the motor mount bolt snapped off in the motor. I never thought I needed to carry a screw extractor with my bag of tools.... :( Crap! I am not sure if that will even work yet, because I still haven't had an opportunity to asses the damage. I will keep you all updated.
 
wasn't trying to rub it in, sorry it looked that way :???: 2.5k miles and still using same studs/nylocks/no locktite but i'm obsessive about checking everything.

anyway, there's been some good luck around here extracting the studs, so i'll cross my fingers for a good repair, let us know 8)
 
when mine broke, it was flush with engine
I used a dremel to cut a slot in the stud and used a screwdriver to extract it
 
Smart man :cool: Way to use your head.....obviously not just a hat rack. :D :D :D

Hopefully mine is close enough to the casting that I could do that as well. From first glance, it looks like the whole thing ripped out threads and all. Unfortunatley, I am at work and I haven't been able to get a good look to see how bad it is. Thanks for the tip though :D :D :D

The fun continues...after removing the motor from the bike, the bolt snapped off with part of the bolt flush with the casting, and the other portion below the casting. I tried cutting a notch in the bolt and use a screwdriver to get it out, but couldn't cut a deep enough notch. So, after getting very frustrated, I pulled out the drill and started with a small bit and worked diligently with a screw exctractor bit which did nothing but put a nice shiny counter sink mark on the bolt. Arghh :censored: :censored: Kept going up in drill bit size and working the screw extractor and stripped about a good 1/4 in of the threads going into the motor. I thought I was going to have to pull out a tap and re-thread the sucker. There was enough thread to still securely attach the motor back on. After securing the motor, I added the screw just above the motor mounts (Which barely fit infront and in back) that typically attach the water bottle cages and to my surprise it has made a significant improvement in reducing the amount of vibration from the motor. This may sound dumb but the bike feels more solid. I will post a pic when I get a chance if anyone is intersted.

Thanks for all the help! :D :D
 
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