Engine failure and Wont start

Mar 16, 2016
118
0
16
america
I've run almost 5 tanks of gas and it's well broken in and been running great. I was about 15 mles into a trip going around 30mph and the bike lost power (full throttle got me 20 mph). I tried to shut it off but nothing happened so i braked to a stop which cut the motor off. It then smoked (from the motor not the exhaust) And now when i try to start it it makes a high pitched noise instead of the usual throaty turn over. I've been running it a little lean i think so that could be it? Please if anyone has any ideas to fix it i need it to ride to work.
 

crassius

Well-Known Member
Sep 30, 2012
4,032
156
63
USA
that squeak is most likely the head gasket leaking - take off gasket & if not burned through, clean it & turn it over, re-torque head bolts (6mm-6-8ftlb, 8mm=10-12ftlb)
 

leo

Member
Jul 20, 2015
250
0
16
southern wv
the head gasket is the flat thing sandwiched in between the jug and the head.
hopefully, that's all it is. an easy (and cheap) fix.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
237
63
up north now
Thats why we use blue locktite, so we don't have to tighten 'em more than once.

Re-tightening them, or checking them all the time will tend to over torque them, or possiblly strip them or the stud.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
237
63
up north now
Never had a problem with stretching, loctite, or head gaskets.
I've only re-checked torque OCCASIONALLY, only to find everything was fine.

Constantly "checking" them can lead to over torquing, unless one uses a good torque wrench, and very carefully.
 

crassius

Well-Known Member
Sep 30, 2012
4,032
156
63
USA
one way to 'check torque' is to use a paper towel wrapped around an old hacksaw blade to wipe all the way around the seam where head meets cylinder - any oil residue found means torque problems
 

2door

Moderator
Staff member
Sep 15, 2008
16,335
141
63
Littleton, Colorado
Let's clear the air here. Re-checking the torque isn't tightening anything. As long as the fastener hasn't loosened from the original torque value simply applying a torque wrench to it and determining that it is still tight runs no risk of damaging a fastener's threads or whatever it is threaded into.

Where the problem comes is from a person wanting to see a turn on the wrench every time he/she 'checks' the tightness. Doing that multiple times will assure that the fastener, or whatever it is threaded into will eventually fail.

If a good quality torque wrench is used and the setting is the same as the original value then the wrench will let you know if the fastener has loosened or not. If it hasn't then leaving it alone won't compromise anything. If, however, the torque value is exceeded, or if you're using a cheap discount store torque wrench that doesn't always read the same, you stand a chance of damaging the fastener or threads.

Any fastener that is subjected to heat/cool cycles, such as cylinder head bolts, intake or exhaust manifold fasteners should be 'checked' periodically because the heat/cool cycles can change the tightness due to expansion and contraction. By 'check' that means seeing if the original torque value is still there. It doesn't mean getting another turn or half turn, or even a quarter turn on the wrench.

Anyone disagree?

Tom
 

Chaz

Well-Known Member
Jun 3, 2012
1,004
70
48
Vancouver, British Columbia
My previous answer was too vague. I did not quantify "regular". Even though I am a chimp and prone to fiddling with my nuts, I only check them if I hear a noise or feel a difference in performance. During break in it's a different matter and I check more often.

Anyway, great post Tom. I think you have a keeper for the glossary and I'd be willing to bet that you had that in mind when you crafted your words.