Subject: Camshaft Timing
Author: joe jump
Date: Sep 6, 2001, 7:31 AM
Post ID: 1708135319
Hello Loopers,
My inquiry has to do with camshaft timing an engine with the original
gear driven timing chest (pre-73), and on a machine that is not a Loopframe
(V-7 Sport). I applogize for drifting off topic, but since the engine in my
machine is so similar to an Ambassador engine, I thought you all wouldn't
mind. And perhaps the discussion would be enlightening to fellow loopers.
My concern is the lack of power my machine has in the upper half of
the rpm range-it seems to run out of breath at about 4500-5000 rpm (redline
indicated at 7500 rpm) in top gear, which is an indicated 80-90 mph.
Mechanically, I believe it to be fine, showing 16k on the clock, valves
adjusted & ignition timing set as per spec, compression reading of 150 & 152
psi. The air plenum and intake runners were removed and K&N filters
substituted. It has the spec jets, needles, & slides. The original Shark
Gills have been opened up substantially to where it's pretty roudy. Although
I haven't done a proper plug chop, there is absolutely no indication that
the mixture is lean; if anything it's on the rich side. I opted for a 110 x
18 rear tire vice the OEM 3.50 x 18 dimension because I wasn't comfortable
with the load rating of the latter. Below 3000 rpm the bike is somewhat
gutless, compared to my 750 Norton, but you can feel the torque building
pretty quick between 3000 & 4500 rpm, especially in 3rd gear!;) But even
slight grades on the interstate at 4500 in fifth cause a noticeable labor,
and opening the throttle yields little more than more exhaust noise. I never
hear any pinging but I always run premium fuel as per Guzziology
recommendations. The V7 Sport cam is quite radical, only out-done by the
B-10, and should provide a good amount of power on the top end. It just is
not there!
I am not the original owner of this bike, and it's past history is an
unknown. I'm starting to suspect that the cam may be either timed too far
advanced, or maybe even the wrong one installed. Looking at the factory tech
manual last night revealed that the cam gear has 52 teeth and that there are
5 holes in the cam gear in which the drive dowel can be inserted. It apears
there is plenty of room for error here, and I'm planning on fitting a degree
wheel & chcking it as soon as I can tear myself off from riding it-still
great fun to ride!
Has anybody out there had any experiences that sound similar to this?
Are there any words of wisdom that you could pass down to me about this
process? Any help would be appreciated-Thanks!
Joe in St Louis
P.S. I do have a loop too - a '68 V700
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