80 MOTORCYCLE CLASSICS September/October 2019
KEITH’S
GARAGE
“The short answer is no,
ethanol affects fuel-injected bikes too ...”
Charging questions
Q:
I have a 1966 BSA Lightning, a
1970 Honda CB750 and a 1974
Norton Commando that all use Podtronic or
other aftermarket solid state rectifier/regula-
tors for lead acid batteries. I would like to
upgrade to lithium iron phosphate batteries
and would like to know if I will be okay using
the current voltage set points for lead acid
batteries, or do I need to use rectifier/regula-
tors specific for lithium batteries? Thank you
for any help.
Wayne Robertson/via emailA:
My opinion for a long time has
been that most of the older
bikes don’t have the robust charg-
ing system necessary to keep a lith-
ium iron phosphate (LiFe) battery fully
charged. I recently spoke with Rick of
Rick’s Motorsport Electrics to see if
things had changed. He said that most
LiFe batteries like the charging voltage
to be 14.2 volts, and not much higher or
lower than that. I don’t know what the
charge cut-off point is for Podtronics,
but the older Lucas Zener diode starts
dumping voltage to ground in the 13-volt
range. For the British bikes I’d stick with
my usual recommendation of a good
absorbed glass mat (AGM) battery for
energy density and leak-proof design.
Rick did say that he had a plug and play
regulator rectifier for the CB750 that
would work well with a LiFe battery.Ethanol and EFI
Q:
I enjoy reading your column every month
and I turn to you with a question. Are
fuel-injected bikes less affected by the ravages of
ethanol gasoline than bikes with carburetors?
Robert Lazzaro/
Hopewell Junction, New YorkA:
The short answer is no, ethanol
affects fuel-injected bikes too, but
in different ways. The fuel still seems
to go bad faster than pure gasoline,
and will still draw moisture out of the
air. Most fuel-injected bikes are going
to have a fuel pump, which can get
gummed up and seize. I suppose the
injector nozzles could crust over too,
but would hope the injector pressurewould overcome that. My routine for
carbureted bikes is to turn off the taps on
the way home and try to enter my garage
on fumes to help keep the carburetor
bowls clean. Since you can’t do that with
a fuel-injected bike your best bet would
be using a fuel stabilizer additive.Kickstarter troubles
Q:
Hi, Keith, I’ve been a longtime reader
and now I actually have a question of
my own. The knuckle of the kickstarter on my
beloved 1971 OSSA Pioneer snapped violently.
Read, mid-kick! To my great surprise there are
new knuckles available. But here is the problem,
post dismantling the broken knuckle from the
lever. My question is about the little rod. Now
obviously this rod mates to the dimpled areas on
both the original and new knuckles, acting as
a position locator or such. My question is, how
and where in relation to the kicklever itself is this
rounded-end little rod inserted and kept in place
during reassembly? I have all the pieces, I think.
What I think I am missing may be a tiny spring
which acts on this rod. But I can’t find a drawing
that tells me exactly where and with what, if any-
thing, this little position rod is mounted. Please,
Keith, I do love my OSSA and want to be sure
this goes back together properly. And thank you
for your monthly column.
Max Rockatansky/via emailA:
I haven’t found a good engineer-
ing drawing of the kickstart lever
assembly, so I’m going to have to make
an educated guess as to how it all goestogether. There is probably a hole in
the lever part of the assembly that
may even still have the spring in it.
Triumph/BSA have a similar setup
as do many other vintage bikes. If
the spring is found, I usually pack
the hole with heavy red grease and
push the spring and plunger back in
place. Often I find I can then hold the
plunger in place with a finger while
pushing the splined shaft back into
the lever. If that doesn’t work you can
use a closely sized socket, pipe or a
shim as a guide/shoehorn, to push the
new shaft in while compressing the
spring and plunger. Hope this helps.
And thanks for your kind words.Plug fouling
Q:
I have a 1965 Triumph T100 500cc.
I’ve restored it externally to look like my
1964 but have not cracked the engine. My prob-
lem now is the plugs are fouling. My solution so I
can ride is to carry clean plugs and change them
when fouling occurs. I’ve run a compression test
and the readings are a little below the minimum
value. My local mechanic, who is quite good with
Triumphs said he has seen them run with levels
lower than mine and not have problems. The
plugs are wet black and I assumed oil. Maybe
I’m wrong and it’s gas which would be carbure-
tor. May I have your thoughts on this? I’m try-
ing to sell the bike and I’d like to fix the problem.
Both plugs foul at the same rate. Thanks!
Ed Gottshall/via emailA:
Ed, you didn’t mention how many
miles were on the engine, but a
common problem with these engines is
worn valve guides. With that you would
have fairly normal compression, but con-
stant oil leaking down into the cylinders.
If you want to investigate further, pull
the intake manifold and exhaust pipes
and look for fresh oil on the back of the
valves. If those seem normal, then I’d
try dropping the carburetor needles one
notch and with new plugs; see if that
changes the plug colors.Email questions to keithsgarage@
motorcycleclassics.com or write:
Keith’s Garage, Motorcycle Classics,
1503 SW 42nd St., Topeka, KS 66609Ready to take your classic queries: Tech Editor
Keith Fellenstein.