CB160 Blue on White maybe

Rod pin bores

I should have cleaned up and looked a little closer at these before.

First the crank in the engine I'm planning on using.
Right side. I'd say, Bad.
Y7O6j5N.jpg


Left side. I'd say, Ugly. 1/8" wide pothole
iRhvWiR.jpg



Now crank from the spare engine.
Right sie. I'd say, Good.
m5h4QhQ.jpg


Left side. I'd say, Bad. Looks worse than it feels.
yCJndRj.jpg




Current crank is Bad and Ugly. Spare crank is Good and Bad. Swapping cranks is a lot of work for only partial remedy.

The FSM does not have much to say here. I used a new wristpin to feel the wiggle. There are no oversized pins available from Honda like the 305s have, that I know about. I assume any fix would involve getting the rod out of the crank for repair or replacement and then crank reassembly.



Bottom line: What are the chances for even limited or moderate usage for either crank. Anybody rebuilding cranks somewhere?
 
I’m no machinist, yet likely not worth having that pressed apart and then reassembled for the work and cost involved. I would be looking for a used crank or parts motor. They show up on Kijiji here from time to time for pretty cheap money.
 
Lots on EBay for $50US+ so reasonable. eBay item number:224959178189
 
I think you are right Flyin900. After spending more time with a new wrist pin in the spare motor crank, twisting, rocking, lifting, I think that will work ok, for a while. There is barely any play in the worst side, as bad as it looks. I may pick up a set of new Asian replacement rods for a later date crank project.
HONDA CB175 CL175 CD175 CA175 SL175 CB160 CL160 Connecting Rod set made Japan | eBay

I think this shows how easily damaged those small end bores are from oil contamination and neglect. Since both cranks have the worst wear on the left side, I wonder if the oil flow to the left side there is a factor, also.

Both engines were abused; the first one with ground aluminum from the slapping cam chain and the second, the spare, with shreds of RTV silicone sealant found in the oil.
 
Rings

Ring gaps are good. Well under the 0.8mm limit. I measured them all in each bore. The tighter bore came in around .26 compressions and .15 oil, the looser bore around .4 compressions and .36 oil, close to the standard range.

I noticed that the pistons were not identical as one had the arrow on the crown and the other had IN, denoting direction.

IHOlNeI.jpg



After I get the cranks swapped, I should finally be ready to move ahead.
 
ballbearian said:
I think you are right Flyin900. After spending more time with a new wrist pin in the spare motor crank, twisting, rocking, lifting, I think that will work ok, for a while. There is barely any play in the worst side, as bad as it looks. I may pick up a set of new Asian replacement rods for a later date crank project.
HONDA CB175 CL175 CD175 CA175 SL175 CB160 CL160 Connecting Rod set made Japan | eBay

I think this shows how easily damaged those small end bores are from oil contamination and neglect. Since both cranks have the worst wear on the left side, I wonder if the oil flow to the left side there is a factor, also.

Both engines were abused; the first one with ground aluminum from the slapping cam chain and the second, the spare, with shreds of RTV silicone sealant found in the oil.
Click to expand...

Yes the old cam chain rubbing the tunnel, it will total shell bearings pretty quickly in a more modern motor. My CL77 had every ball bearing damaged with micro abrasion, which could be felt when spinning them. Hence the replacement of all the ball bearings in my motor.

More of a spectator now on these forums and builds, since it is way cheaper. :)

Realistically how much will you ride a CB160 bike? So maybe rolling the dice and using those parts, yet your into it with new cylinder boring and pistons and rings. A replacement crank if it can be verified as decent is cost effective.
 
Flyin900 said:
Yes the old cam chain rubbing the tunnel, it will total shell bearings pretty quickly in a more modern motor. My CL77 had every ball bearing damaged with micro abrasion, which could be felt when spinning them. Hence the replacement of all the ball bearings in my motor.

More of a spectator now on these forums and builds, since it is way cheaper. :)

Realistically how much will you ride a CB160 bike? So maybe rolling the dice and using those parts, yet your into it with new cylinder boring and pistons and rings. A replacement crank if it can be verified as decent is cost effective.
Click to expand...

For me at this point, it's all a hobby and a challenge, so cost is kind of like tuition. Being realistic has always been hard for me.
I do ride these small bikes a lot (for me) but, yes, it may take a few years to get 2K miles logged. I just want to ride it hard and not worry if it doesn't last as long as a new one.
So, I've pulled the crank out of the spare motor and need to clean it up and open up the current motor (and find some more issues?) and complete the transplant.

I'm enjoying myself at this phase of life and know that things will change (they always do). I hope you are enjoying that beautiful collection of yours too.
 
I think this shows how easily damaged those small end bores are from oil contamination and neglect. Since both cranks have the worst wear on the left side, I wonder if the oil flow to the left side there is a factor, also.

[/QUOTE]

Wrist pins are splash fed, No?Duhhh.
 
Both cranks are out and cleaned. The spare had a good looking tranny and there was light rust on the gears in the current motor so may as well finish cleaning out the cases and swap the cleaned up gears too.

Current motor with light rust
Oe2EHYF.jpg


Spare motor, looks good
MB07FCc.jpg



Was able to measure the small end rod bores much better with a calipers. The bad/ugly one was 14.10 and 14.08mm, the good/bad was only 14.05, 14.06.
The FSM doesn't have squat for specs. The table in the back has small end rod clearance as " 3 (.12") " ??? I think their editor must have been MIA.
 
That second tranny looks way better that the original. It does pay to have a parts bike or two to scavenge parts, since buying from other sellers eventually adds up to the cost of the total build.
 
Flyin900 said:
That second tranny looks way better that the original. It does pay to have a parts bike or two to scavenge parts, since buying from other sellers eventually adds up to the cost of the total build.
Click to expand...

I'm putting the spare engine purchase to good use.
 
More greasy problems

Cracked bearing retainer groove in the case and ****-eyed shaft pins. Can it be ignored? Main shaft, clutch side, upper case.

tHzW3vo.jpg


Same shaft, other end. I have the spare for this.

zuGmeDz.jpg


Counter shaft pin bent too. Homemade kicker shaft pin stuck in there for angle. Shows wear on case wall from gear.

nMa6buK.jpg


Spare lower case has footpeg bolt hole issues

3Z5qpdH.jpg


More cleaning before final mix and match choices are made. Even the crank is getting outer roller bearing swapped due to some rust pitting.

The head may not leak, so far, but I haven't had the cam and rockers out yet.
 
I don't know if you can get by with that set ring groove cracked like that. Maybe a full cleaning with solvent and carb spray to get any oils out of it and then JB Weld to make it solid again. It would seem the clutch rod pressure would be against the wide side of the set ring groove so it might work. Seems one of the POs was pretty ham-fisted.
 
Acetone boils at 132F, you can probably use a turkey baster or kitchen syringe (flavor injector?) full of that to slowly degrease cracked areas like that.

Thoughts?

You can also thin JBweld with acetone to help it flow into areas like that.
 
I would have that lower case half welded, then repair the threads, and assemble the engine with the the spare cases. JB weld is a poor substitute for cast aluminum, that kind of damage is likely to have distorted the cases in other areas too.
 
mike in idaho said:
I would have that lower case half welded, then repair the threads, and assemble the engine with the the spare cases. JB weld is a poor substitute for cast aluminum, that kind of damage is likely to have distorted the cases in other areas too.
Click to expand...

That bearing serves clutch and primary drive stesses. The other end bushing and pin show the same direction end thrust damage. The countershaft has pin damage in the opposite direction. I wonder what could have caused this, all are straight cut gears?

You have the only sensible approach, I think.
 
Here’s a complete set of engine cases for $20US that look pretty solid with the bottom one looking better than yours.

eBay item number:
233214613973
 
I'll focus on clean up of the spare upper case first. The bad bottom in the pic was the spare so I might have a good set.
 
Will I ever finish anything? It's been raining a lot so may as well clutter up the shop some more. Quite a production in there.

EsbEVjd.jpg
 
ballbearian said:
Will I ever finish anything? It's been raining a lot so may as well clutter up the shop some more. Quite a production in there.
Click to expand...
Do you have a motorcycle jacket for each motorcycle?

69 CB350K1/68 CB450K0
 
Last edited by a moderator:
Sometimes I think the stuff in my garage gets together overnight and reproduces. And the piece of wisdom from Ray Magliozzi on "Car Talk" years ago still echoes in my head -

"If you start working on one carburetor, pretty soon you'll have two."
 
wentwest said:
Sometimes I think the stuff in my garage gets together overnight and reproduces. And the piece of wisdom from Ray Magliozzi on "Car Talk" years ago still echoes in my head -

"If you start working on one carburetor, pretty soon you'll have two."
Click to expand...
This is true. I bought a CB350 last fall. Now I appear to have a Cb450 in the garage too.

I wonder what will be there next year?

69 CB350K1/68 CB450K0
 
Sweet, like this project! Great idea with the liquid tape repair. Keep the tricks flowing.
 
Question. 160 cam lobe heights, can't seem to find any numbers in the nice drawings, info boxes and spec pages in the FSM.
 
Well, there seems to be a general lobe-otomy on cam lobe info, both here and on a couple FB groups, I queried.
So, here are the measurements of the two camshafts I have that I would characterize as on the low side of moderate wear, given the overall condition of other motor parts.

Cam#1 (original)
Left Intake 24.61 Left Exhaust 24.38 Right Intake 24.61 Right Exhaust 24.37


Cam#2 (spare)
Left Intake 24.66 Left Exhaust 24.62 Right Intake 24.62 Right Exhaust 24.59

These all are total heights (not subtracting base circles)


Maybe someone will find this useful (maybe even comment). Sort of a message in a bottle.
 
ballbearian said:
Maybe someone will find this useful (maybe even comment). Sort of a message in a bottle.
Click to expand...

It is a shame that there's no good source of info for you with respect to the cams, at least so far. There are other members who own CB160s, right?

Thanks for putting your numbers out there for others to reference!


Edit: There is some discussion of the CB160 lift on this thread.
 
Time to jibe and put it back together. Cleaned both sets of cases, in and out. Swapped cranks and tranny gears. I'm using the original cases with the cracked bearing retainer clip groove because logic (to me) dictates that normal stresses are not effecting that crack (must have been hamfisted, as AD said, prior assembly) and bronze support shaft caps seated nicely with good locating pins. Everything turns and spins very smoothly and all gear shifting seems perfect.

New timing chain in place. Pre fitting the cases looked good, so ready to seal and mate.

Waiting on machinist to finish the +.75mm piston bores and then choose which new set of jugs is going in. I can use the other in the spare motor build after I get the footpeg mount TIG welded or pass it along as I also have a loose honed standard bore jug with either good used pistons or another new set of standard pistons I bought. I know I went crazy.

g7y89AX.jpg



The machinist said they have a press and can do crank work so I might get a set of asian rods and do a crank job if I want to continue the crazy thing. I wonder if the center crank roller bearings are available.

After it runs and I ride it, I may come to my senses and just get back to my blue Dream project.
 
stl360+450 said:
It is a shame that there's no good source of info for you with respect to the cams, at least so far. There are other members who own CB160s, right?

Thanks for putting your numbers out there for others to reference!


Edit: There is some discussion of the CB160 lift on this thread.
Click to expand...

Thank you! That forum thread was fun and interesting info on performance stuff. My question was merely about trying to find a basis for determining wear limits.
I saw a few familiar names there, more to explore.
 
(Do the Ton:) 160 cam has less lift than 175/200. CB160 is 3.7/3.4mm and 175/200 are 3.9/3.7 more or less.
Click to expand...


Makes sense that you would like to know service limits, but I thought the lift info (assuming it is correct) might make for a useful comparison with your measurements. Have you measured the base?

Are there any aftermarket manuals for the CB160? If so, might they be of any help?
 
stl360+450 said:
Makes sense that you would like to know service limits, but I thought the lift info (assuming it is correct) might make for a useful comparison with your measurements. Have you measured the base?

Are there any aftermarket manuals for the CB160? If so, might they be of any help?[/COLOR]
Click to expand...

I just measured the bases at 21.04-21.05 for all, so that puts the lift right at the DTT info, about 3.6/3.3. That is intake/exhaust I assume. Thanks for helping me to work through, new territory for me.

Clymer's and Chilton's both got nada.
 
ballbearian said:
The machinist said they have a press and can do crank work so I might get a set of asian rods and do a crank job if I want to continue the crazy thing. I wonder if the center crank roller bearings are available.
Click to expand...

Well that's interesting to hear, I'd imagine there are few around these days who would want to bother with them so that could be an asset in the future if they're willing to take in work shipped to them from out of state.

Your parts are looking nice and clean, ready to rock and roll.
 
ballbearian said:
My question was merely about trying to find a basis for determining wear limits.
Click to expand...

With respect to the wear limits, I would think the wear limits from other Honda models of similar design might help inform ballpark numbers. I'm including a clip from the CB350 FSM below. This would suggest that on a CB350 you could lose up to 0.18mm on the lobe heights. I don't have a good sense for how that relates to changes in lift, but it makes sense that the greatest cam wear would occur on the larger parts of the lobe.

Screenshot_20220918-082126.jpg

Just ideas. Perhaps others with more experience can chime in about whether this would make sense or not.
 
With respect to lost horsepower, the loss of .007" in lobe height probably wouldn't be noticed by the average owner. Of course, on the 350 and DOHC 450/500T with eccentric rocker arm shafts it would also cause a small loss of valve adjustment range too but on the adjustable tappet engines like the other twins and singles I doubt it would account for much in either category.
 
stl360+450 said:
With respect to the wear limits, I would think the wear limits from other Honda models of similar design might help inform ballpark numbers. I'm including a clip from the CB350 FSM below. This would suggest that on a CB350 you could lose up to 0.18mm on the lobe heights. I don't have a good sense for how that relates to changes in lift, but it makes sense that the greatest cam wear would occur on the larger parts of the lobe.

View attachment 17394

Just ideas. Perhaps others with more experience can chime in about whether this would make sense or not.
Click to expand...


So roughly about 0.2mm wear on 350s. I do find me looking at my 150 and 305 specs to make an educated guess.
 
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