'75 Honda CB400F Super Sport: First Bike Help!?
Don Wagner
brother has fixed up a 1975 Honda CB400 Four Super Sport. I took
it for a test ride. But, I don't know a thing about bike. It runs well
and looks good (a yellow bike, but the tank is primer gray, and there
is some rust on the pipes, etc-- not serious). He is asking $800. I am
tempeted to go for it, but I want more info on the bike. Does anyone
have any or know of a source for info on the bike, and any idea if the
price is right?
Oh, and I am tall (6'6") and a bit worried about the size of the bike.
But I figure a smaller bike is good for starters (took the MSF course).
--
************************************************************************
Don R. Wagner (wag...@ocf.berkeley.edu) * "People who never
College of Chemistry, Saykally Lab * get carried away
University of California at Berkeley * should be"
(h) 510-524-3471 (lab) 642-1047 * -Malcomb Forbes
************************************************************************
Thomas Jones
worth the $800 price if original and complete.
The bad news: As a "Daily driver" the bike stinks. It will be no
where near as reliable as a late model bike with a solid state
ignition system.
--
Tom
Kalessin
Um, why not just put an electronic ignition in it? The points weren't bad
either, they just needed adjustment and replacement every 6,000-8,000
miles.
A CB400F is a fine and very reliable bike. It's biggest weakness was the
rather poor cam chain tensioner setup, which tended to freeze up and break
off the adjuster lock bolt. I fixed a couple of those. The downside of the
cam chain tensioner was that the way it was made and the original way you
were supposed to use it didn't tension the chain properly so the chain ran
loose and consequently didn't last as long as it should have. Tensioned
the right way (staticly, same way you do a 750 or 550 single cammer), they
last just fine.
Lovely bikes with good handling and decent brakes for the time.
Godfrey
--- <D> --------------------------------------------------
Godfrey DiGiorgi - Kale...@eWorld.com - Cupertino, CA USA
Scott Wheeler
> I am in the market for my first bike. I have a friend whose
> brother has fixed up a 1975 Honda CB400 Four Super Sport. I took
> it for a test ride. But, I don't know a thing about bike. It runs well
> and looks good (a yellow bike, but the tank is primer gray, and there
> is some rust on the pipes, etc-- not serious). He is asking $800. I am
> tempeted to go for it, but I want more info on the bike. Does anyone
> have any or know of a source for info on the bike, and any idea if the
> price is right?
They were never very popular in the States, but were a cult bike in the UK. Basically
they're a bored out CB350 engine in a CB250G5 frame, with a 4:1 exhaust. Both the
ancestors were dogs, but the 400/4 was really nice. The engine is almost bulletproof,
except that the cam-chain tensioner wears out (not a serious problem). The front brake
swinging caliper may gum up, requiring you to strip and clean it. They can be a bit short
of ground clearance on the right hand side if it has the original pipes. They do about
105mph with a midget riding it, i.e. not very fast by modern standards, but fast enough.
There were loads of tuning bits available (460 overbore, Yoshi cams, turbo charger etc.),
but this would be difficult to find now. I can't comment on the price by US standards,
but I'd bite his hand off if I found one in the UK at that price.
scott
Jason Surace
(Kalessin) wrote:
So how does one statically tension the chain?
I have an '86 CB450SC which uses the same lame cam chain tensioner.
I've noticed the way the shop manual says to tension it (with the engine
running) doesn't work at all. In fact, I _did_ break the damned locknut
off at the time, necessitating a top-end tear-down to replace it.
Aaaarghh! Nothing like a simple bit of maintenance suddenly turning
into an annoying project!
- Jason Surace
ja...@galileo.ifa.hawaii.edu
R Glenn Stauffer
> >
> > A CB400F is a fine and very reliable bike. It's biggest weakness was the
> > rather poor cam chain tensioner setup, which tended to freeze up and break
> > off the adjuster lock bolt. I fixed a couple of those. The downside of the
> > cam chain tensioner was that the way it was made and the original way you
> > were supposed to use it didn't tension the chain properly so the chain ran
> > loose and consequently didn't last as long as it should have. Tensioned
> > the right way (staticly, same way you do a 750 or 550 single cammer), they
> > last just fine.
> >
> > Lovely bikes with good handling and decent brakes for the time.
> >
> > Godfrey
> >
> > --- <D> --------------------------------------------------
> > Godfrey DiGiorgi - Kale...@eWorld.com - Cupertino, CA USA
>
>
> So how does one statically tension the chain?
1) Turn the engine so that the #1 cylinder is at TDC on its
compression stroke. Make sure the T (1.4) timing mark is
aligned with the scribe mark on the contact breaker baseplate.
2) Look through the contact breaker baseplate and continue to rotate the
engine until the spring peg is just to the right of the timing mark.
This puts #1 at 15degrees after TDC so the chain tension is at the rear
of the engine.
3) Loosen the tensioner locknut and allow the tensioner to turn and
adjust itself. This doesn't always work, so I turn the screw to tension
the chain myself. Once it is set, hold the screw in place and tighten
the locknut.
That is for a 550, so getting the engine to 15dg ATDC might be different
as may be the operation of the tensioner.
Glenn Stauffer
Kennett Square, PA
john relph
I run a 400/4 as an occassional bike, its marvelous on sunny days around Surrey
lanes
Being so smooth its feels as if its faster than it is, which may not be a bad
thing. The brakes are not so good and two up are dire, it is best as a solo
bike.
The camchain can be changed in situ, you need a rivited link which comes with
most aftermarket suppliers. A small hammer and a piece of iron to use as a
base are all you need, also lots of rags to stop bits falling down into the
engine. Split the old chain and use it to pull the new one through and rivet it
together. Sounds crude but mine worked well, so far.
The camchain adjuster does not work, the tensioner jams.
To adjust the chain remove the front engine mount plates on one side and remove
the blank bolt in the crankcase that is revealed. Slacken the adjusterlock
beneath the blank. Put a slim steel rod down the blanking hole, you may need to
bend this, and tap firmly down with a hammer. This moves the tensioner.
My bike went from a clattering heap to a smooth machine when I did this.
Take time on the tappets, they are a drag but have to be done.
--
_J_O_H_N___R_E_L_P_H________________ GL 500 400/4
Kalessin
>
>To adjust the chain remove the front engine mount plates on one side and
remove
>the blank bolt in the crankcase that is revealed. Slacken the
adjusterlock
>beneath the blank. Put a slim steel rod down the blanking hole, you may
need to
>bend this, and tap firmly down with a hammer. This moves the tensioner.
Jams happen when the lock bolt is overtightened. That damages the
tensioner plunger which then cannot be pushed out properly by the spring.
The lockbolt only takes a little torque to do its job; the plunger has a
ramp which prevents it backing up when the lockbolt is tensioned. The
workaround suggested is reasonable although it's easy to apply too much
tension to the cam chain this way if you're not careful.
The correct fix is to replace the tensioner plunger after stripping the
bottom engine case off. It's a pain in the butt.
Godfrey
john relph
kale...@eworld.com "Kalessin" writes:
What is the point of this if the basic engineering and design is at fault ?
You might as well use the workaround and save yourself a lot of work, you are
lucky it can be done.
Also bikes like this one are not used as every- day hacks. Mine has only done a
couple of thousand miles since the fix and is still quiet, but I will do
another one soon - when it warms up.
--
J_O_H_N___R_E_L_P_H_______________ GL 500 400/4_