BritBike Forum logo
BritBike Sponsor BritBike Sponsor BritBike Sponsor
BritBike Sponsor

BritBike Sponsor

BritBike Sponsor
BritBike Sponsor BritBike Sponsor BritBike Sponsor
JWood Auctions JRC Engineering dealers JWood Auctions
Home | Sponsors, Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons, "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Member Spotlight
Soup Dragon
Soup Dragon
South Cotswolds, England
Posts: 21
Joined: October 2006
Show All Member Profiles 
Shout Box
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Who's Online Now
19 registered members (Alan_nc), 193 guests, and 435 spiders.
Key: Admin, Global Mod, Mod
Newest Members
Konaflyer, Begbie, Andrew Fallo, Zack Banks, 1966g10
10418 Registered Users
Top Posters(30 Days)
btour 89
Rohan 81
Triless 77
reverb 75
Popular Topics(Views)
710,228 mail-order LSR
Forum Statistics
Forums34
Topics68,305
Posts665,025
Members10,418
Most Online3,995
Feb 13th, 2017
Like BritBike.com on Facebook

Previous Thread
Next Thread
Print Thread
Rate Thread
Tight Timing Side Masin Bearing #327341
08/09/10 9:25 pm
08/09/10 9:25 pm
Joined: Nov 2008
Posts: 13
Shropshire, UK
W
wavey_davey Offline OP
BritBike Forum member
wavey_davey  Offline OP
BritBike Forum member
W

Joined: Nov 2008
Posts: 13
Shropshire, UK
Guys,
I need your help!

Am half way through a bottom end rebuild on my T140, to fit some newly acquired Megacycle cams. I never liked the lack of spec that came with the "half race" cams I put in about 15 years ago, purchased from a well known UK belt drive supplier, but bike was running ok before the tear down, if we ignore my little "foible" of failing to spot a gearbox leak and running the gearbox dry with inevitable consequences, ahem..

Anyway, split the cases this afternoon (to reveal cam peaks and followers like a ploughed field! But that's for another day), drive side came away as good as gold, but crank seems reluctant to let go of it's hold on the timing side roller and case.

I fitted a NUP306ETN D/S roller at the same time as the cams, maybe 15 years but only 5-7000 miles ago. Lack of any other markings on the bearing (I fitted it so I could see the numbers) means I suspect it is a CN clearance, but not sure whether this is even relevant?

Tried dropping crank on it's nose on a piece of wood, nothing.
Repeated after warming cases in oven for 20 mins at 160 C. Spit didn't sizzle, so maybe too cool, but bearings seems to have shifted a few mm in it's crankcase housing, but didn't want to come out all the way?

I am taking the line that whatever applies to the Drive side roller should apply to this, so maybe it IS a case of "bought a CN but really needed a C3"? Even in my youthful exuberance I don't recall any reluctance for the bearings to spin on installation, and they seem fine now, but I struggle to remeber last week's events, never mind 15 years ago!

Any tips gratefully received..

Dave


'68 bonnie from Illinois, bought whilst drunk on eBay
'75 bonnie, from near Birmingham (Midlands, not Alabama) bought whilst young and foolish 30 years ago
'72 rocket 3 bought, apparently, in a fit of blind optimism
Support Your #1 BritBike Forum!

Check out British motorcycles for sale:
British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America
Check out British motorcycles for sale:
British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America
Re: Tight Timing Side Masin Bearing [Re: wavey_davey] #327353
08/09/10 10:25 pm
08/09/10 10:25 pm
Joined: Jul 2007
Posts: 451
redondo beach, ca
Bob G Offline
BritBike Forum member
Bob G  Offline
BritBike Forum member

Joined: Jul 2007
Posts: 451
redondo beach, ca
The bearing clearance rating shouldn't have any bearing on being tight in the cases.
I have had the best luck drilling a couple of small holes in the case that line up with the outer race. I then use a small driver to knock them out after I heat up the cases. There was a Triumph service bulletion showing this. Another member sent it to me on this forum. I could find it for you if needed.


Bob Gregor
Re: Tight Timing Side Masin Bearing [Re: Bob G] #327549
08/10/10 9:29 pm
08/10/10 9:29 pm
Joined: Aug 2001
Posts: 3,348
Michigan, USA
BONZO R.I.P. Offline
In Remembrance
BONZO R.I.P.  Offline
In Remembrance

Joined: Aug 2001
Posts: 3,348
Michigan, USA
I would use a propane torch to warm the aluminum case around the bearing keeping the heat on the alu might let it grow away form the bearing as it will expand faster than the unwarmed steel.

FWIW-BONZO

Re: Tight Timing Side Masin Bearing [Re: BONZO R.I.P.] #327557
08/10/10 10:01 pm
08/10/10 10:01 pm
Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
J
John Healy Offline

BritBike Forum member
John Healy  Offline

BritBike Forum member
J

Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
NUP306 is a Metric bearing and could not be used on a T140 on the drive side which is an inch dimension. It also has a single side shoulder and a loose side shoulder which allows removal of the inner race (which is pressed onto the crankshaft) just by sliding them apart. That is of course if you placed the loose side shoulder on the outside!

NUP306ET would a proper fit on the timing side as this bearing on a T140 is Metric. This NUP306 ET bearing was used on the timing side of the last couple years of the T140 and can be retro-fitted to earlier year T140's.

So the question: are we talking drive side or timing side?


Last edited by John Healy; 08/10/10 10:06 pm.

Re: Tight Timing Side Masin Bearing [Re: John Healy] #327565
08/10/10 10:33 pm
08/10/10 10:33 pm
Joined: Nov 2008
Posts: 13
Shropshire, UK
W
wavey_davey Offline OP
BritBike Forum member
wavey_davey  Offline OP
BritBike Forum member
W

Joined: Nov 2008
Posts: 13
Shropshire, UK
Aargh, what am I like. I DO mean the timing side, you're quite right John. In my defence it was very late when I typed that post last night, after a day of spanner twirling and crankcase juggling.
I just meant by my comments in the original posting that removing it from the crank and the cases should be the same as if it was a (more common) Drive side roller, though not necessarily true due to it's different construction as you have reminded me John?

I've avoided local heating of the cases Bonzo due to advice on this forum to try and avoid localised heating due to risk of distortion, though I must admit it's commonly used in lots of reference articles (Gary Chitwood 650 bonnie book for example.)
I can't remember how I assembled it, guidance was thin on the ground in those pre forum days. I can read the bearing number through the timing side case aperture, but that probably doesn't mean a hell of a lot! I'm guessing both sides of the bearing were marked as they were seperate parts??

I'll take a photo after work tomorrow which shows a small gap, that wasn't there before, between bottom of case housing and the bearing.

Thanks for all the advice so far guys.

Dave


'68 bonnie from Illinois, bought whilst drunk on eBay
'75 bonnie, from near Birmingham (Midlands, not Alabama) bought whilst young and foolish 30 years ago
'72 rocket 3 bought, apparently, in a fit of blind optimism
Re: Tight Timing Side Masin Bearing [Re: wavey_davey] #327567
08/10/10 10:48 pm
08/10/10 10:48 pm
Joined: Nov 2008
Posts: 13
Shropshire, UK
W
wavey_davey Offline OP
BritBike Forum member
wavey_davey  Offline OP
BritBike Forum member
W

Joined: Nov 2008
Posts: 13
Shropshire, UK
I've also just found this on another forum, it explains the sequence to use in fitting the bearing.
The last post refers to the same difficulty I'm having, and seemed to refer to lots of heat and brute force!

http://www.triumphrat.net/classic-vintage-and-veteran/104246-roller-bearing-main-3.html


'68 bonnie from Illinois, bought whilst drunk on eBay
'75 bonnie, from near Birmingham (Midlands, not Alabama) bought whilst young and foolish 30 years ago
'72 rocket 3 bought, apparently, in a fit of blind optimism
Re: Tight Timing Side Masin Bearing [Re: wavey_davey] #327577
08/10/10 11:48 pm
08/10/10 11:48 pm
Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
J
John Healy Offline

BritBike Forum member
John Healy  Offline

BritBike Forum member
J

Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
Quote:
lots of heat and brute force!


A couple of points:
I totally disagree with the use of "lots of heat and brute force"!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

You shouldn't need any more than 200 to 200 F to heat the case. The whole case and not just heating until 200 is reached, but heating where the cases get to soak up the 200 F degree heat for ten minutes or so. They need to be soaked in the heat which gives them time to expand. Thermal expansion isn't instant!!! I use an old oven.

And with local heating, you can be sure the cold metal around it will not expand from thermal expansion leaving the only place for the metal to expand to is by clamping on the bearing harder. This might be OK of you like brute force and hammers or the bearing is already loose in the case, but when you get a stubborn one it just makes things worse.

The bearing in question is made up of three pieces.
An outer race and bearing in a cage.
An inner race which should have its single shoulder against the flywheel.
A removable outer shoulder that looks like a heavy washer which goes in last and is under the timing pinion washer.

Thus when you remove the timing pinion, and associated timing pinion washer, the bearing's shoulder washer should be free to be removed. This allows the flywheel and the inner race to slide out of the outer race and the bearing rollers. No heat required to this stage.

Now, if you installed the loose shoulder against the flywheel all bets are off.


Lots of heat anneals the aluminum and force brake things. Of course this is OK because I have made a good living fixing these things after Bubba got out the torch and sledge.


Re: Tight Timing Side Masin Bearing [Re: John Healy] #327590
08/11/10 1:51 am
08/11/10 1:51 am
Joined: Jul 2009
Posts: 3,549
Vic. Australia
P
Pete R - R.I.P. Offline
In Remembrance
Pete R - R.I.P.  Offline
In Remembrance
P

Joined: Jul 2009
Posts: 3,549
Vic. Australia
I'd rather use heat than force,anytime.I'd have it in the kitchen oven and heat it to 300 degrees F,if necessary (I do have an oven in the shed,though).
I'm pretty sure no annealing occurs in any aluminium alloy below 570 degrees F.,and it can be higher.Although it doesn't have much strength AT the elevated temperature,temperatures between 212-400F. are used to speed up the age-hardening process and increase yield strength.
I expect that an old set of cases would already be fully age-hardened,but I don't think temperatures above 212F will cause harm,if heated evenly in an oven.

Re: Tight Timing Side Masin Bearing [Re: Pete R - R.I.P.] #327619
08/11/10 7:40 am
08/11/10 7:40 am
Joined: Oct 2004
Posts: 4,429
Melbourne Australia
Tiger Offline
BritBike Forum member
Tiger  Offline
BritBike Forum member

Joined: Oct 2004
Posts: 4,429
Melbourne Australia
As I understand your process you have the drive side crankcase half, suspended on the bearing, and are attempting to release the bearing outer race from the crankcase half by jarring the crankshaft end down against a piece of timber ?

If so I have two reasons why this is not a good idea.

First off the crankcase half is of light alloy and will have bugger all inertia.

Secondly the inadequate crankcase mass is not Concentric around the bearing and and your efforts will tend to cock the bearing outer race within the case, a sure path to defeat and could also damage the crankcase main bearing cavity.

My solution would be to suspend the crank vertically on timber blocks under the crankcase half and wait for the bearing to creep out, if in a hurry I would put the lot in boiling water suspended as above.

The laws of Physics cannot be defied and Pete R is absolutely corrrect, "Only a fool obtains by violence that which may be obtained by stealth".


1969 TR6R
7.62 x 51 is not a maths puzzle.
Re: Tight Timing Side Masin Bearing [Re: Tiger] #327655
08/11/10 4:23 pm
08/11/10 4:23 pm
Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
J
John Healy Offline

BritBike Forum member
John Healy  Offline

BritBike Forum member
J

Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
Pete and Tig
This thread provides one example of how vulnerable people are to advice about heat and force. But it is not the only example.

There was one example a few years ago that was brought to my attention by a local engine balancer. A Britbike member read that he should heat his crankshaft when removing the sludge tube threaded plug. When my friend was presented with the crankshaft for balancing the entire timing side of the crankshaft, from the flywheel to the T/S main shaft, was black. A good indication that the metal was heated to well over 500 degrees or dull red.

When it comes to heat I find a lot of people who have every tool in the Snap-On catalog approach a job that requires heat with out any of the requisite tools and little, if any, understanding of the job at hand. More is better seems to rule the day. "Slow and easy" gets swept away, or dismissed, by "more is better."

Few have access to a thermostatically controlled oven (well, not if they don't want a heated divorce), even fewer have temperature measuring "sticks" (Tempastick, Thermomelt and Tempilsticks are brands I have used) or a modern heat measuring gun. But all have, or have a buddy that has an acetylene torch (and you can do a fair amount of damage with a Mapp gas torch as well).

So when I recommend heat I always err on the low side, knowing full well if I recommend 200F, and "more is better" is still at work, the part is going to see a lot more heat than 200F, especially the thinner sections.

Failing to understand that thin sections of the casting heat up a lot faster than thicker sections, they check the heat on some large section of the casting. They read books, written by "experts" and follow their advice and localize the heat around the bearing forgetting that the part of the casting around the bearing that holds the seal is very thin and heats up much faster than the thicker areas around it. I know Gary very well, and I know he would never apply heat to the thin section of a casting. That said, I have not see a lot of engine cases where the "mechanic" melted the part of the casting that holds a seal, or the like.

I find it much safer to use as little heat as required, applying it evenly so the entire casting has come up to temperature, and allow it to sit for a period of time to allow thermal expansion to do its job. There is also issues of damaging the bearing when it is going to be re-used.

If the bearing is being stubborn, and the race is accessible, plunging a rag that has been soaked in ice water into the bearing will often provide the only force needed to release the bearing.

Originally Posted By: Tigger
As I understand your process you have the drive side crankcase half, suspended on the bearing, and are attempting to release the bearing outer race from the crankcase half by jarring the crankshaft end down against a piece of timber ?


Holding the crankcase at either end, one drops the crankcase 6 to 8 inches allowing the timing side end of the crankshaft to strike the end grain of a piece of hard wood. The wood must be on a hard surface like a cement floor. Its the shock that will release the crankshaft from the bearing (This assumes that the bearing wasn't Loctited onto the mainshaft and the fit of the bearing's inner race is a nominal fit on the main shaft. It will not release the bearing from the crankcase).

The force is a little more than hitting the end of the crankshaft with a large leather mallet. If one is to consider the amount of crankshafts one sees at flea markets with the oil feed snub of the T/S main shaft mushroomed beyond belief the hammer must be the tool of choice for a lot of people when doing this job.
HTH

Last edited by John Healy; 08/11/10 4:24 pm.

Re: Tight Timing Side Masin Bearing [Re: John Healy] #327695
08/11/10 9:10 pm
08/11/10 9:10 pm
Joined: Nov 2008
Posts: 70
UK
Z
zhango Offline
BritBike Forum member
zhango  Offline
BritBike Forum member
Z

Joined: Nov 2008
Posts: 70
UK
Originally Posted By: John Healy


The bearing in question is made up of three pieces.
An outer race and bearing in a cage.
An inner race which should have its single shoulder against the flywheel.
A removable outer shoulder that looks like a heavy washer which goes in last and is under the timing pinion washer.

Thus when you remove the timing pinion, and associated timing pinion washer, the bearing's shoulder washer should be free to be removed.

I've only fitted one of these and it was well over 10 years ago but from memory I thought the loose thrust washer was fitted first into the crankcase half followed by the outer race so it was trapped?

Re: Tight Timing Side Masin Bearing [Re: John Healy] #327701
08/11/10 9:31 pm
08/11/10 9:31 pm
Joined: Nov 2008
Posts: 13
Shropshire, UK
W
wavey_davey Offline OP
BritBike Forum member
wavey_davey  Offline OP
BritBike Forum member
W

Joined: Nov 2008
Posts: 13
Shropshire, UK
John, Pete, Tiger,

Thanks again for the considered responses.

Let's just be clear, and apologies in advance if this seems overly defensive. I WASN'T advocating the approach taken by the person in the thread I referenced, hence the mention of "brute" force and the exclamation marks?

I also am NOT having a go (as we Brits say) at Gary Chitwood either, just pointing out the plethora of opinions and different approaches to apparently basic tasks like removing and fitting bearings in alloy castings. I sensibly just took a look at all the information available to me, including the 3 photos on page 59 of his book, showing localised heating of casings to aid removal of 3 different bearings.

My only attempt (using a plumbing type domestic blowtorch) to heat the WHOLE of the T/S crankcase resulted in so little heat being applied overall (I could still comfortably hold most of the case half) I concluded that the only way to apply sufficient heat to the case using that torch was to apply localised heat, and I agree with John's rationale as to why that wasn't a good idea. Not saying it doesn't work for some, just not my preferred option.

I also took a deliberately cautious approach to heating in the oven, for all the reasons stated.

Part of my day job in leading a team of Network failure analysts for a very large Telecom company, is listening very carefully to experts in their field, but not being afraid to probe, question and clarify their responses?

I now conclude, thanks to your help, that the same approach I used earlier should work, but with perhaps a little longer in the oven (and POSSIBLY a little higher heat), having some rags and iced water to hand, utilising the same piece of oak I used last time, but this time on a solid concrete floor (I did it 1st time on the wooden deck! doh!) will hopefully be successful!


I'll keep you informed!

Thanks again

Dave


'68 bonnie from Illinois, bought whilst drunk on eBay
'75 bonnie, from near Birmingham (Midlands, not Alabama) bought whilst young and foolish 30 years ago
'72 rocket 3 bought, apparently, in a fit of blind optimism
Re: Tight Timing Side Masin Bearing [Re: wavey_davey] #327720
08/11/10 11:54 pm
08/11/10 11:54 pm
Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
J
John Healy Offline

BritBike Forum member
John Healy  Offline

BritBike Forum member
J

Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
{quote: zhango] A removable outer shoulder that looks like a heavy washer which goes in last and is under the timing pinion washer.[/quote]

In this application you are right. Because of the size of the hole in the crankcase the washer is dropped into the crankcase first. Thank you for keeping me on the straight and narrow!!!!

But, I am more than a bit confused about all this as the crankshaft should just slide out of the crankcase. In fact it should just fall out. Is the washer possibly between the inner race and the flywheel?

And another thing about heat and this particular bearing. A lot of these bearings are now coming with plastic cages. It is just one more thing to think about when heating the cases.

No need to worry about Gary, he has a long list of beautiful restorations to back up his accomplishments. He also has the right to his opinion.

Have to go home and hit the Cheerio's


Re: Tight Timing Side Masin Bearing [Re: John Healy] #327777
08/12/10 10:36 am
08/12/10 10:36 am
Joined: Nov 2008
Posts: 70
UK
Z
zhango Offline
BritBike Forum member
zhango  Offline
BritBike Forum member
Z

Joined: Nov 2008
Posts: 70
UK
John - you were right first time about the position of the bits when you said:-
"An inner race which should have its single shoulder against the flywheel.
A removable outer shoulder that looks like a heavy washer which goes in last and is under the timing pinion washer."

The loose washer really is next to the timing pinion and when the pinion is removed the crankshaft can slide out(with the inner race still attached)leaving the loose washer still trapped by the outer race in the crankcase. The only bit wrong was the loose washer goes into the crankcase first before the outer race

Last edited by zhango; 08/12/10 10:39 am.
Re: Tight Timing Side Masin Bearing [Re: zhango] #327868
08/12/10 7:54 pm
08/12/10 7:54 pm
Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
J
John Healy Offline

BritBike Forum member
John Healy  Offline

BritBike Forum member
J

Joined: Mar 2005
Posts: 10,221
Boston, Massachusetts
Got out the Mapp bottle, set-up the dial indicator bore gage, set-out the electronic heat thermometer and heated a set of cases, and the phone started to ring.

Heating the bearing housing in a circle about 1" away from the bore, here's what I discovered so far:
1. Although the bearing housing on the drive side 750 crankcase didn't get smaller, well maybe a .001" or so at 120ish degrees, the expansion was very uneven around the bore. At 160F the bore had expanded .0025" in one direction and didn't move at all in the other.
2. At 200F the bore had expanded pretty evenly to .004" one way and .005" the other, BUT when removing the heat the bore it started to shrink back almost immediately. By the time I had put the gas bottle down and picked up the bore gage the case had closed up to .003" and shrinking.
3. The thin section of casing adjacent to the bearing bore that holds the seal never really got that hot, Even though the area adjacent to the bore got above 100 degrees, the thin part of the casting struggled to hold 150 or less.

Then the phone took over my life...

Try to do more tomorrow and get it into the oven and see what happens.
HTH
J



Moderated by  John Healy 


Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Powered by UBB.threads™ PHP Forum Software 7.6.2