CB350 Engine in Frame

Completed the engine rebuilding on the bench. Barrels seated nicely after getting the bottom O rings in their grooves. this also made it easier to get the cam chain and sprocket on and sitting at TDC. Then installed the Valve pins, my new Rockers, adjusted the valves, top caps on and torqued the engine studs so now to to put the lump back in the frame.
I had to think about this for a bit as It was going to be a one man job.
Contemplating the frame I decided that since the wheels were off, to remove the foot peg bar, fold up the main stand and lower the frame to the ground. This would mean I only have the thickness of the bottom tube to lift and manoeuver the lump. Not wishing to damage my shiny black powder coating I wrapped the bottom tubes in Masking Tape.
The process went surprising well and I had completed it in 20 minutes....

( can AD rotate this pic please? it refuses to upload correctly even after I have rotated it on my computer.) - Done

On the bench

On the floor

In the Frame, engine was tilted back to fit the top cam cover and stud nuts under the top frame member.
I straddled the frame and since it is on the ground my feet were flat and easy to move the lump about with a hand each side.

Bottom mounting bolts in...I was expecting this bit to be difficult as the mounting ears had Powder Coating on them but the engine slipped in okay. The only tightness was the bottom front left bolt distance piece need some persuasion.
And best of all after removing the masking tape no chips or scratches.

... now to build the wheels. First time I have done this . should be interesting

Cheers

Gary
Auckland

Gary - is there a direct metal to metal connection between the frame and engine?

You may need to remove some of the powder coating as the ground path for the ignition is through the engine to the frame and into the battery.

I only bring it up because you mention the powder coated ears.


- 1972 CL350
- 1985 VF700F

GaryJames said:

The only tightness was the bottom front left bolt distance piece need some persuasion.

Click to expand...

I assume (and hope) you're referring to the spacer in between the lower left front motor mount tab and the lug on the lower case. Don't leave it out if you weren't referring to it.

I'll rotate the pic for you, but if you just open the pic in MS Paint and rotate 90° right, then save and replace the pic you can do what I do.

It will be easier for you to lay the engine over on the right side and drop the frame over the engine. Much better control.

Ed, I was also concerned about this but have used two star washers under a large washer on the rear bolts nuts.
I also used a star washer under the battery ground/negative cable where it connects under the head of the top right rear bolt head.
The idea being that the small sharp points on the star washer push through the Powder Coating....seems to work okay.
After tightening them I have a good chassis connection to frame as measured with my sensitive Ohm meter. I fact it is close to the resistance of the leads when connected together.
LDR, I did consider this method but since I have the rear guards, swing arm and main stand already on it was getting heavy at one end.
If the frame was bare then I think that method would work okay.

cheers

Gary

I have a supplimentary question please...
In my third pic down, of the left hand side, Engine in frame and just below the swing arm large nut with grease nipple there is a shaft sticking out from the frame with what looks like two separate bearing surfaces.
I am assuming this is for earlier bikes that had a linkage mechanism connected to the gear shift pedal and gear change shaft from the engine. I have none of these items so either my bike came from Honda without ( supposedly a 1973 K4 ) or the PO discarded it and fitted a direct gear change arm on the gear shaft.
Since I rode this bike every workday with the direct arm change pedal for 7 years back in the 80's and never had any trouble with it I am assuming it will be fine..
I wonder why Honda designed it with the linkage?

Gary

K4 had the slop linkage, K5 frame doesn't have that stud on the frame.

Unless it is a restoration the one piece shift lever is so much better that I don't even bother trying to fix the multi linkage set up.

GaryJames said:

I wonder why Honda designed it with the linkage?

Click to expand...

I suspect it was a carry-over thought from the days prior to the release of the 350 when Honda used a heel-toe shifter on some bikes, ease of shifting in the 350's case because of more leverage with the longer shift lever.

GaryJames said:

I have a supplimentary question please...
In my third pic down, of the left hand side, Engine in frame and just below the swing arm large nut with grease nipple there is a shaft sticking out from the frame with what looks like two separate bearing surfaces.
I am assuming this is for earlier bikes that had a linkage mechanism connected to the gear shift pedal and gear change shaft from the engine. I have none of these items so either my bike came from Honda without ( supposedly a 1973 K4 ) or the PO discarded it and fitted a direct gear change arm on the gear shaft.
Since I rode this bike every workday with the direct arm change pedal for 7 years back in the 80's and never had any trouble with it I am assuming it will be fine..
I wonder why Honda designed it with the linkage?

Gary

Click to expand...

When I got my 1971 CL350K3 from barn storage, it had the direct lever and the bare mounting stud for the original shifter. It is strongly against my nature to detab or cut off any original parts of a motorcycle frame, so I slipped a piece of rubber hose, a stainless steel washer, and an acorn nut from Ace Hardware on there to make it less noticeable. It also protected the threads on the end of the mounting stud.



Later, I had a chance to buy the original linkage at a very cheap price (somebody took off the slop linkage in favor of a direct lever). To my eyes, the linkage setup looks rather elegant. Off came the direct lever and the cover-up parts.



And on went the original parts:



I did it a little differently than stock. I used the acorn nut because I already had it. I also inserted the pins from back to front for easier assembly / better frame clearance. Here's how the fiche says it should be:



I found that the shifter was a little higher than I liked, but that was no problem because item #6 in the diagram has a LH thread on one end, and a RH thread on the other. By loosening the jam nuts (items #11 & #12), and rotating item #6, you can change the span between the levers. This raises or lowers the shifter relative to the footpeg. Many of you are familiar with a setup like this for your rear-set controls.

With a minor tweak to the linkage rod, I took another test spin and found that I liked this much better than having the direct-mounted shift lever. I've run it this way for quite a while now and I am happy with it.

I did fine tune it a bit this past summer. I looked everywhere, with no luck, to find a shim to remove the in/out play of the lever on the frame mounting stud. I needed a round washer-shaped shim, 14mm inside diameter, 19mm outside diameter, and .55mm thick. I finally got a friend with a lathe to make me one. The linkage works better than ever now.

Ray

A quick update on where my re-build is at. Had to travel out of town for a few days so no garage time for a bit unfortunately.

Did the valve clearance adjustments after I got the rocker shafts oriented the right way with the small detent facing outward.
Then on with both main side covers using Honda Bond as sealant.
Kick starter on and working smoothly and gear change cycles in and out of neutral okay. Other gear selections I assume will work when the engine internals are rotating.
Clutch cable attached and adjusted.
Next job is to assemble both wheels with new spokes and true them up.
Never done this before ( may have already mentioned this elsewhere sorry ) but youtube videos have given me some confidence and guidance so I will give it a shot.
......


And last big expense for this job is two new Mufflers, probably the clubman type from Common Motors. But I am not liking the freight $$$ to NZ !!


Cheers

Gary
Auckland

Things are looking good.

GaryJames said:

Then on with both main side covers using Honda Bond as sealant.

Click to expand...

Just to be completely clear, you used Hondabond in addition to the gaskets for the crankcase covers?

GaryJames said:

Never done this before ( may have already mentioned this elsewhere sorry ) but youtube videos have given me some confidence and guidance so I will give it a shot.

Click to expand...

I know YT videos can give you the visual of the internal parts and how they look when assembled properly (assumedly), but you have to be careful about the methodology used in many of the videos out there so don't take everything they say or do as gospel.

Thanks AD, yes Honda Bond with gaskets.
I also take YT videos with a grain of salt…
the re-spoking ones all pretty much offer the same advice on lacing.
I plan to mount the completed wheel horizontally in my vice using the axel then rig up a couple of pointers to true it up.
I will post some picks at that time.

cheers
Gary
Auckland

I think I have a problem....
On the bench I installed the cam with the small auto advance locating spigot in the 12 o'clock position and the horizonal line on the cam gear cog at the top as per the FSM and my Haynes manual. With the left hand piston at TDC; I checked this with a torch down the plug hole and observed the crown of the piston at the top.


I took this picture at that time:

ignore that fact that is this pic the line is not quite horizonal, I had to shift the cam chain by one link on the cog to correct.

When I rotate the rotor to the LT mark to set the rocker/valve gap on the compression stroke I cannot move the rocker adjusters.
If I then rotate a further 360 and bring to LT mark up again I can make the adjustment. However the small spigot is now at the 6 o'clock position and to me the engine is not on the compression stroke for the left hand cylinder.



I carefully identified the compression stroke by watching the exhaust valve when turning the rotor , after it closes the piston travels down and the Inlet valve opens. When the piston then travels up the Inlet valve closes and with both valves closed I have compression measured with finger over the plug hole. I am sure this is the compression stroke.

I have searched VHT and found a couple of threads on doing this and it seems to me I have done it correctly but I do not understand why I can't do the valve/rocker clearance adjustment at true TDC on the LT mark.

All the literature I have, Haynes Manual, Honda FSM and watched a couple of Youtube videos for this on the CB350 I am now worried some thing is not right with my assembly but before I pull the lump back out on to the bench to do it all again I though getting some advise from VHT might be advisable.
I have been laying awake at night cogitating over this !!!

cheers

Gary
Auckland

LT with pin at 12 o'clock is not where the left side valves get adjusted. Pin at 6 with rotor at LT is where the adjustment is done.

Get some sleep.

Many thanks Boomer.
I was over thinking it.

Gary

After my mental abberations regarding the cam timing earlier a small package arrived being my new front drive sprocket.!
( nothing like a package to blow away the blues... )
So on its goes and very little play compared to the old one.

https://youtube.com/shorts/ttfBwhB4uYg?feature=share

Cheers

Gary