Date: Fri, 10 Sep 1999 21:10:19 -0500
From: "Doug Nelson" <nelson@camalott.com>
Subject: "Bob Hunter"  : Vmax Fw: 92 v-max

Bob Hunter wrote:  I own a 92 Max and I just got home from Sturgis and my
bike sat for 2
 weeks  When I went to start it ,  made a loud thump and I now have 20 psi
in  3  cylinders and 90 in the other. It ran fine when I parked it now its
dead  in  the water! I am looking for some one to help me get it running
again. The  shop I have it in says They want to sell me a used motor because
they say  it  will cost more to rebuild than a used one but they still cant
tell me why  it  has no compression. Any thoughts?

Bob your not so bad off. If you know a little about a motor read on if not
ask your dealer (reputable) to these checks. First of all a used engine is
no better than  you really got except it will run, but with no idea of the
abuse it has went through. You could have your own engine rebuilt buy some
shop like PCW for around $1000.00 or less and have a fresh engine, but lets
look at what is your problem.

1) First remove and inspect all spark plugs. Look very closely to see if any
of the end electrodes are bent, distorted, pushed in, if so only concentrate
on these cylinders. if not do all checks listed below on all cylinders.
2) Now remove your valve covers.
3) Put your engine on the center stand or jack the rear wheel off the
ground.
4) Now remove the front left flywheel cover small timing inspection sight
plug
5) Put the engine in 5 gear
6) Bump the rear wheel so the fly wheel is moving counter clock wise until
the T-1 mark on the fly wheel is aligned with the case cover timing arrow
(inside the plug hole).
7) Check to see if that the cams are facing away from each other not pushing
down on any of the valves (compression stroke).
8) If not rotate the engine counter clock wise another 360 degrees to align
the arrow on the case cover to the T-1 mark on fly wheel, now you should be
on the compression stroke for that cyl.
9) Now look at your timing mark at the end of the cam to make sure the small
timing hole on both cams are  straight up, should be center to the line mark
on the out side end of the cam cap
10) If they are aligned then the aft cams are still timed,  chain has not
slipped.
11) Rotate the engine counter clock wise another 360 degrees plus 70 more to
the T-2 mark (for a total of 430 degrees)
12) Look at the front cams to make sure the large timing holes are at top
and center to the end cap out side line
13) If that was good, your front cams are still timed, chain has not slipped
14) Bump the rear wheel counter clock wise until the cylinder your
inspecting is at the top, "should be in the compression stroke" (the cams
are pointing away from each other (in a no valve lift position, valves are
fully closed and not being compressed) if not rotate the engine another 360
degrees C/, now it  should be in the compression stroke.
15) Now bump the rear wheel while shifting gears until your in first gear,
but don't move the cams from their position
16) lower the bike onto the ground
17) Now go buy or borrow a engine leak down tester with a spark plug thread
size of 12mm.
18) Borrow a air compressor, doesn't have to be a big one just one that goes
to around 100 PSI. If the air compressor doesn't have the same quick
disconnect coupler as the compressor go to sears and buy one that will fit
it
19) Screw the 12 mm leak down tester fitting and the hose that goes to it
into the cyl being tested.
20) Hook the air compressor to the leak down tester hose/ gage) Remove both
forward and aft valve covers.
21) If you have a stock exhaust remove the exhaust pipe so you can put your
ear up to the exhaust out let, if you have a after market pipe remove the
end pipe so you can put your ear up to the pipe with no obstruction from
your ear to the head exhaust port.
22)Remove carburetor  airbox or air filters what ever you might have
23) Have some one sit on the bike to keep it from moving when you pressurize
the cylinder.
24) Start out by pumping around 60 PSI into the cylinder
25) Open your throttle fully open.
26) Now with throttle fully open put your ear down against the top of
carburetor for the cyl being tested.
27) If you hear allot of air coming out from the intake you have a bent or
broken intake valve.
28) Now put  your ear against the #1 cylinder exhaust pot outlet, if you
hear allot of air coming out from the exhaust port you have a bent or broken
exhaust port valve.
29) If those test were good take off your oil fill cap.
30) If you hear allot of air going into the case than you have a serious
piston problem break down.
Now with the information you just got you can determine what the cost will
be to fix the engine and you now know what's wrong with it. Take care and
e-mail me soon.
Doug Nelson