CB72/77 Crankshaft bearings

[SMBH]

HERE I GO AND IF I OFFEND YOU, YOU MAY BE THE PERSON THIS IS ADDRESSED TO!
I'm amused by some things I see that are Over Kill to fix or repair a simple part in these engines when plenty parts are out here and $$$ seem to be the Road Block. to some ?????????????????
As I see what comes next I never see any $$$ saved.
To me it seems that in the end more $$$$ and time are spent for simple repairs.
I am impressed at how some are so capable to use tools or have parts made at machine shops that the average sole who wants to JUST GET ONE RUNNING AND RIDE ABLE will never have but salivate (drool) at the process shown on this forum.
Yes I'm impressed on how a SPECIAL FITTING can be made to allow a Bearing that doesn't cost all that much can be changed but WILL BE SPECIAL in ones engine.
I shutter to wonder how much if any $$$ you save with all the things I've observed in the last months.
I can and have rebuilt several REALLY SORRY engines for +- $950.00 US and the sad thing with this the cost to ship is usually near $100.00.
If I wasn't so lazy I'd show all the simple ways to take these engines apart and then how easy they go back together.
Special Tools! Hammer, flat chisel, vise grip pliers, HAMMER DRIVE to loosen/remove Screws jis #3 screwdriver, long point punch, wood to put on the 2 Deadheaded Nuts at the engine center to split the cases, Bass rods to knock the cams out of the head. Sharp Putty Knife to remove gasket maternal.
Probably the tool most will not have is a Torque Wrench but OLD FOLKS have learned how to KNOW WHEN THAT NUT/BOLT is good and tight and will DO THE JOB! I HAVE 3. OTHER MAY NOT!
What allows me to be happy as I rebuild engines is that I understand "IT'S JUST A MACHINE" AND PAYING ATTENTION TO WHETHER A PART IS GOOD OR BAD is #1.I don't do things to fix a non existent problems or Puff Up my Chest with SPECIAL REPAIRS when the very simple HONDA parts are still out here and as many of you know I sell them at reasonable prices.
Most of you who I address this diatribe to have purchased HARD TO GET PART from me.
ENOUGH!!!!!!!!!!!!!!!!!!!!...............lm

Mike

That's the route I was going to take. Steel or alloy for the sleeve?

Sorry I didn't get around to it for you yet......

G

Alloy, machine shop said it would be best., they made it very tight so I will put the bearing in the fridge and use a hot air gun on the sleeve to fit it and some bearing lock.

No problem Graham I had to have a new first gear bush made infact I had two made and they made a very nice job of them, so I got them to made the bearing sleeve while they were at it.

Also looking at replacing the other side with a 6206 STD bearing and sleeve.

While I have your attention the right side outer bearing the smaller of the crank shaft bearings 30 x 62 x 16 has a hole for lokating the knock pin, the hole in the bearing on my bearing is 6mm offset from centre and the knock pin is stepped down to 5mm so when the bearing is installed there is a lot of play is this so ?
Also the oil hole is covered when the bearing is installed and the inner side of the bearing is sealed not allowing oil into the bearing so all that is left is the very small channel by the bearing, im thinking of removing that inner seal.
Your thoughts on it would be very welcomed.

Thanks LM for your reply,
I put up the posting hoping to help any one that have a problem obtaining the very hard to get here in the UK crankshaft bearing over the pond in the land of plenty more Honda's were sold and it seems to me there are so many more parts.
Some companies will not ship to the UK.
When was the last time you looked at Ebay for a crankshaft bearing for a CB72/77 give it a try.
Now if it BSA or Triumph parts then we have so many over here were they were built.
Torque Wrench I do have some spanners. (that my friend is a joke)

[LOUD MOUSE]

As for this bearing.
Unless the bearing area on the crank shaft is damaged I use the original PIN rolleres.
Only time I goto the Roller bearing is of the shaft is damaged.
The replacement bearing comes with both sides open or like yours one side covered.
I remove that cover when I use them.
As to finding parts this forum has many members who sell/trade parts.
I've sent parts back to Japan,, Germany, Australia, Italy and South Africa.
Was that replaced bearing damaged?. ....................lm


While I have your attention the right side outer bearing the smaller of the crank shaft bearings 30 x 62 x 16 has a hole for lokating the knock pin, the hole in the bearing on my bearing is 6mm offset from centre and the knock pin is stepped down to 5mm so when the bearing is installed there is a lot of play is this so ?
Also the oil hole is covered when the bearing is installed and the inner side of the bearing is sealed not allowing oil into the bearing so all that is left is the very small channel by the bearing, im thinking of removing that inner seal.
Your thoughts on it would be very welcomed.[/quote][/quote]

Thanks LM for your reply,
I put up the posting hoping to help any one that have a problem obtaining the very hard to get here in the UK crankshaft bearing over the pond in the land of plenty more Honda's were sold and it seems to me there are so many more parts.
Some companies will not ship to the UK.
When was the last time you looked at Ebay for a crankshaft bearing for a CB72/77 give it a try.
Now if it BSA or Triumph parts then we have so many over here were they were built.
Torque Wrench I do have some spanners. (that my friend is a joke)[/quote]

[R100]

I pretty much agree Ed.
The K.I.S.S. principal (Keep It Simple Stupid) usually serves me well.
I use a torque wrench where it's important to have things equally tight, like head bolts. I go to about 80-90%, them feel the last bit.
For other things I trust my wrist to find "snug", "tight", "good 'n' tight", and "that's f***ing tight!". Like Steverino, I can usually feel when aluminium threads are about to become unhappy.
I put in Allen head 6mm bolts for the engine side covers. With a T-handle Allen key, and my feeble old body, I would bet good Scotch that I end up at 5 - 7 foot pounds.
Thanks for the flattened chisel tip - sometimes a round punch is just wrong.

[SMBH]

LM you wrote -

As for this bearing.
Unless the bearing area on the crank shaft is damaged I use the original PIN rolleres.
Only time I goto the Roller bearing is of the shaft is damaged.
The replacement bearing comes with both sides open or like yours one side covered.
I remove that cover when I use them.
As to finding parts this forum has many members who sell/trade parts.
I've sent parts back to Japan,, Germany, Australia, Italy and South Africa.
Was that replaced bearing damaged?. ....................lm

The replaced roller bearing has a very slight play in it and I intend to replace it as I have no idea as to what tolerance one can go to on a roller bearing my policy is if there is any movement in a roller bearing then replace it , thanks for the confirmation regarding removing the covered side of the bearing I could not see any reason why it should be covered.

L/M You are obviously a very nogible person when it come to these engines and have had a lot of experience stripping and restoring them that is why I post here.
Thank you for your time.

[sixtiescycle]

HERE I GO AND IF I OFFEND YOU, YOU MAY BE THE PERSON THIS IS ADDRESSED TO!
I'm amused by some things I see that are Over Kill to fix or repair a simple part in these engines when plenty parts are out here and $$$ seem to be the Road Block. to some ?????????????????
As I see what comes next I never see any $$$ saved.

Personally I enjoy seeing and reading about these the innovations and hope Ed's diatribe doesn't discourage others from posting. Not everyone is just repairing/restoring Honda's, myself I also have a collection of Homelite/Bearcat outboard engines, there is a output bearing that is next to impossible to find and your ideas can be used in other applications. Graham's crankshaft rebuild thread was great, something I've wanted to do, not to save $$$ as I have some good used and a couple NOS but more for the experience and satisfaction of accomplishment. I own a lathe, don't use it much and would like to use it more, these posts kinda of inspire me to make some of the parts I've wanted to, a hobby thing. Other enthusiasts in my community can benefit from this by not having to pay machine shop rate while we have beer, cup of coffee and a good old BS session while whipping out a part they may need, not just a Honda part, maybe something for a Marusho, etc.

I'm kind of wondering how this bearing modification will will hold up down the road as the bearing is now smaller than the original application?

From my perspective keep the posts coming, I welcome them, and I own 4 torque wrenches............................

[SMBH]

sixtiescycle wrote-
I'm kind of wondering how this bearing modification will will hold up down the road as the bearing is now smaller than the original application?

The bearing is STD fitting in my unit 500cc Triumph on the drive side and on the other side a plain bearing.

In fact this 6306 bearing fits the following brit bikes

Triumph 3TA, T21, T90 350cc Unit twins Crankshaft D/S
Triumph 5TA, T100, TR5 500cc Unit twins Crankshaft D/S (ball race up to 1967)
Triumph T120, TR6, 6T 650cc Unit twins Crankshaft T/S (metric bearing 1972-)
Triumph T140, TR7, TR7T Trail 750cc Unit twins Crankshaft T/S
Norton Dominator/Model 7 500/600/650cc Crankshaft T/S
Norton Commando 750/850cc Crankshaft D/S & T/S bearing

[sixtiescycle]

sixtiescycle wrote-
I'm kind of wondering how this bearing modification will will hold up down the road as the bearing is now smaller than the original application?

The bearing is STD fitting in my unit 500cc Triumph on the drive side and on the other side a plain bearing.

In fact this 6306 bearing fits the following brit bikes

Triumph 3TA, T21, T90 350cc Unit twins Crankshaft D/S
Triumph 5TA, T100, TR5 500cc Unit twins Crankshaft D/S (ball race up to 1967)
Triumph T120, TR6, 6T 650cc Unit twins Crankshaft T/S (metric bearing 1972-)
Triumph T140, TR7, TR7T Trail 750cc Unit twins Crankshaft T/S
Norton Dominator/Model 7 500/600/650cc Crankshaft T/S
Norton Commando 750/850cc Crankshaft D/S & T/S bearing

I guess where I'm going, the Brit bikes turn a slower rpm than the Jap bikes. Now you are taking a smaller bearing and subjecting it to a higher rpm. Just thinking.............................................