BritBike Forum logo
BritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorThe Bonneville ShopBritBike Sponsor
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
ShoutChat Box
Comment Guidelines: Do post respectful and insightful comments.
Buy BritBike staff a coffee
Buy BritBike's staff a coffeeStill here since 1996 serving BritBike enthusiasts..
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Member Spotlight
hein weijers
hein weijers
The Netherlands..
Posts: 127
Joined: October 2007
Show All Member Profiles 
Newest Members
Egbert JAS, turflok, Carl Courson, Roddy Walsh, Mark Creighton
10779 Registered Users
Top Posters(30 Days)
franko 133
NickL 61
DavidP 59
MarcB 51
Popular Topics(Views)
950,455 mail-order LSR
Forum Statistics
Forums34
Topics67,525
Posts675,891
Members10,779
Most Online14,755
May 5th, 2019
Who's Online Now
56 registered members (Adam M.), 377 guests, and 805 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
how did this happen? #764272 02/02/19 2:58 pm
Joined: Feb 2012
Posts: 65
H
Hjalte Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
H
Joined: Feb 2012
Posts: 65
so i finally got myself together and decided to get rid of those oil spots on the floor, pulled the timing side apart, need new kick seal and a fresh coat of loctite 518 on the flange no problem.
then time for the drive side.. noticed a high amount of metal shavings in the oil. well did not think much of it as i renewd the clutch plates like 1000km ago.. then , after removing the chaincase cover i noticed it was aluminium shavings... hmm chain is steel , clutch is steel , bearings are steel... but after a quick look at the rotor i saw where they came from ..
[Linked Image]
the rotor had scraped against the timing pin on the cover. how is this possible?
its a BSA B40WD 1967.
rotor nut was on tight and tab washer intact.
when i did the clutch 1000km ago there was no problem and have not messed with the rotor during or since doing the clutch.
timing pin was in its correct place, tho quite a bit rounder than it use to.

did notice a noticable slack in the rotor to crank key
did also notice tho that the rotor was sticking out a little bit from the stator, but might always have done this.

took apart the clutch tho and found out i forgot some loctite on the hub screws...
[Linked Image]

any sugestions to how this happend ? (the screws i figured i forgot loctite)


Support Your #1 BritBike Forum!

Check out British motorcycles for sale:
British Motorcycles on e-Bay UK
British motorcycles on e-Bay North America
Re: how did this happen? [Re: Hjalte] #764274 02/02/19 3:36 pm
Joined: Dec 2004
Posts: 9,943
kommando Online Content
BritBike Forum member
Online Content
BritBike Forum member
Joined: Dec 2004
Posts: 9,943
Check the thickness of the Wassell rotor and compare it to the old one, I bet its thicker and so touched the pointer on the timing cover.

Re: how did this happen? [Re: kommando] #764304 02/02/19 9:47 pm
Joined: Sep 2013
Posts: 2,007
Q
quinten Online Content
BritBike Forum member
Online Content
BritBike Forum member
Q
Joined: Sep 2013
Posts: 2,007


Other possibilities along with the rotor mentioned .


The distance piece behind the duplex sprocket
Comes in various thicknesses to allow for Chain alignment
... I think up to 0.7 or 0.8mm between thinnest and thickest .

Or a new / different duplex sprocket ?


... Or did you linish the gasket faces ...or not use a gasket .


.



Re: how did this happen? [Re: Hjalte] #764308 02/02/19 9:54 pm
Joined: Oct 2007
Posts: 1,548
Ignoramus Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Oct 2007
Posts: 1,548
nothing to do with what you are asking but the chainwheel slots sure look badly notched to me .......bet the clutch is a bit of a problem ie not that smooth?.....might be time for a new (or better 2nd hand) one ....just saying


"There's the way it ought to be and there's the way it is" (Sgt Barnes)
Re: how did this happen? [Re: NickL] #764339 02/03/19 3:09 am
Joined: Feb 2012
Posts: 65
H
Hjalte Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
H
Joined: Feb 2012
Posts: 65
Originally Posted by kommando
Check the thickness of the Wassell rotor and compare it to the old one, I bet its thicker and so touched the pointer on the timing cover.

have not changed the rotor.

Originally Posted by quinten


Other possibilities along with the rotor mentioned .


The distance piece behind the duplex sprocket
Comes in various thicknesses to allow for Chain alignment
... I think up to 0.7 or 0.8mm between thinnest and thickest .

Or a new / different duplex sprocket ?


... Or did you linish the gasket faces ...or not use a gasket .




have not messed with the distance piece, tho i noticed there is an aditional washer ยด/ shim behind the sprocket. but it has always been there without troubble.
did use a gasket, hylomar on the cover and grease on the case.

Originally Posted by Ignoramus
nothing to do with what you are asking but the chainwheel slots sure look badly notched to me .......bet the clutch is a bit of a problem ie not that smooth?.....might be time for a new (or better 2nd hand) one ....just saying


the clutch is actualy quite smooth taking the basket condition in to account. but yes it is quite badly notched.

Originally Posted by NickL
How's the primary chain alignment? That will indicate if the sprocket is in the right place.

did not check before i took it apart.. did notice quite some wobble in the chainwheel.
read in my rupert ratio that you can take a bit of the spider to counter this, any one have experience with this method ?

Re: how did this happen? [Re: Hjalte] #764343 02/03/19 3:41 am
Joined: Aug 2001
Posts: 4,779
Mark Z Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Aug 2001
Posts: 4,779
On the A65s I've owned, and also on a TR5T that I happen to be working on, the face of the rotor is recessed from the stator by, I would say, about 1/8 inch.


Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
Re: how did this happen? [Re: Hjalte] #764367 02/03/19 12:51 pm
Joined: Aug 2001
Posts: 4,565
gavin eisler Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Aug 2001
Posts: 4,565
I had to shorten the timing pin on my A65 after fitting a new rotor. I think K has it right, its possibly been rubbing for ages and you just didnt notice.


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: how did this happen? [Re: Hjalte] #764384 02/03/19 4:07 pm
Joined: Dec 2004
Posts: 9,943
kommando Online Content
BritBike Forum member
Online Content
BritBike Forum member
Joined: Dec 2004
Posts: 9,943
Quote
did notice quite some wobble in the chainwheel.
read in my rupert ratio that you can take a bit of the spider to counter this, any one have experience with this method ?


Yes it does work, mount in a lathe and skim a few thou off or if no lathe flatten the end on plate glass and emery cloth. A few thou at the centre creates a lot of movement at the outer edge.

Re: how did this happen? [Re: Hjalte] #764450 02/04/19 1:14 am
Joined: Aug 2001
Posts: 4,565
gavin eisler Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Aug 2001
Posts: 4,565
ive tried that dodge on my A65, years ago, you loose a little wobble, but it doesnt make up for the internal wear on the cush spider and end plates , that can still tilt and cause drag/slip, The spider centre protruding a bit is just the tip of the wear iceberg.


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: how did this happen? [Re: Hjalte] #764451 02/04/19 1:17 am
Joined: Aug 2001
Posts: 4,565
gavin eisler Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Aug 2001
Posts: 4,565
Looking again at the rotor pic, the rub marks are too wide to be the timing pin, that cuts a neat narrow groove, maybe it got bent over? possibly one of the cover plate screws is too long and saying hello to the rotor, or something else got jammed in there , broken chain roller maybe?

Last edited by gavin eisler; 02/04/19 1:19 am.

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: how did this happen? [Re: gavin eisler] #764457 02/04/19 1:55 am
Joined: Aug 2001
Posts: 4,779
Mark Z Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Aug 2001
Posts: 4,779
Originally Posted by gavin eisler
Looking again at the rotor pic, the rub marks are too wide to be the timing pin, that cuts a neat narrow groove, maybe it got bent over? possibly one of the cover plate screws is too long and saying hello to the rotor, or something else got jammed in there , broken chain roller maybe?


Good point, those gouges are wide. This being a '67, I guess it would have an inspection cover over the rotor. Inspection cover mounting screw too long is a good guess. Or, if the rotor is the wrong one, or if it is spaced out too far on the crank, then I suppose the inspection cover screw bosses could hit.

Hmm, four-bolt clutch on a '67?



Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
Re: how did this happen? [Re: Hjalte] #764561 02/05/19 5:46 am
Joined: Feb 2012
Posts: 65
H
Hjalte Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
H
Joined: Feb 2012
Posts: 65
i looks as its the timing pin, but i will do a dry fit and check , i am think i will bring my old clutch plates to work and weld up a locking/counter hold tool for the clutch , making it much easyer to check the allignment , the sprocket and chain does seem to have a "suspicius" wear pattern. if allignment is okay , my guess is that the chain does not like "clutch wobble"
i am guess its a 4 bolt clutch due to it being a "WD" model

Re: how did this happen? [Re: Hjalte] #764619 02/05/19 11:26 pm
Joined: May 2013
Posts: 5,721
Allan Gill Online Happy
BritBike Forum member
Online Happy
BritBike Forum member
Joined: May 2013
Posts: 5,721
I think Mark is thinking A65, afaik all unit singles were 4 spring clutches.


beerchug
Re: how did this happen? [Re: Hjalte] #764818 02/08/19 5:01 am
Joined: Feb 2012
Posts: 65
H
Hjalte Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
H
Joined: Feb 2012
Posts: 65
okay made the tool for the clutch :

[Linked Image]

works like a charm smile

the alignment is way off:

[Linked Image]



will say tho that i am able to "wobble" the basket to fit the alignment....... but not the solution i had in mind.

and the timing pin lines up perfect with the damage to the rotor:

[Linked Image]


so the problem is the sprocket and rotor is to far out.
the extra spacer between the sprocket and crank spacer is the likely reason for this..
the problem is that i have run with this arrangement before without any problems.
is it possible for the crank to start "floating" out ? i find this very unlikly.
but if the timing pin to rotor was very close and the crank floated a thou or 2 this might possible.


Re: how did this happen? [Re: Hjalte] #764825 02/08/19 10:20 am
Joined: Aug 2001
Posts: 4,565
gavin eisler Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Aug 2001
Posts: 4,565
Possibly the front sprocket is the wrong way round? the timing pin has lost a fair bit.
This must have been pretty tight when the case was fitted, was it OK when it was strobed,? that would have caught it ? or somehow the crank has migrated to the primary side ( unlikely if the rotor nut is tight).

Last edited by gavin eisler; 02/08/19 10:26 am.

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: how did this happen? [Re: gavin eisler] #764833 02/08/19 1:07 pm
Joined: May 2013
Posts: 5,721
Allan Gill Online Happy
BritBike Forum member
Online Happy
BritBike Forum member
Joined: May 2013
Posts: 5,721
Originally Posted by gavin eisler
Possibly the front sprocket is the wrong way round? the timing pin has lost a fair bit.
This must have been pretty tight when the case was fitted, was it OK when it was strobed,? that would have caught it ? or somehow the crank has migrated to the primary side ( unlikely if the rotor nut is tight).



Makes sense, the rotor nut isn't fully on either. When checking the alignment, fit all the plates etc in position the spring tension should hold the basket true


beerchug
Re: how did this happen? [Re: Hjalte] #764878 02/08/19 10:09 pm
Joined: May 2004
Posts: 4,055
B
BSA_WM20 Offline
BritBike Forum member
Offline
BritBike Forum member
B
Joined: May 2004
Posts: 4,055
Also check the crank for bending.
Either the rotor is not true to the crankshaft ( highly likely with a Wassel part ) or the cank is bent.
The pin should have cut a groove around the complete circumference of the rotor, not just a short arc.
Also check that the rotor is tight on it's centre .
The early design had a bad habit of separating between the casting & the centre .
In any case that pointer looks way too close to the rotor there should be a good 1/8" between them.
What primary cover gasket did you use ?
The originals was quite thick.
Next, when new there would have been a Lucas rotor fitted so the Wassel was fitted by the previous owner.
Please measure the length of the rotor.
The military B40 down( B40GA ) here use a narrower rotor & stator , but they were 6V.
I think he may have fitted an A65 one to your bike.
Rotors come in 3 or 4 lengths as the output increased.


Bike Beesa
Trevor
Re: how did this happen? [Re: Hjalte] #764886 02/08/19 10:45 pm
Joined: Nov 2012
Posts: 1,104
K
koan58 Offline
BritBike Forum member
Offline
BritBike Forum member
K
Joined: Nov 2012
Posts: 1,104
Nonsense, the evidence is symmetrical, which would not be the case with a bent crank.
I'm sure all the damage was done in a few moments, break the point off, then then rest of it.
For whatever reason, the rotor was ~1/8-3/16" closer to the timing pin than it should have been. The point was taken off the pointer on the 1st hitting of the raised timing pad. Thereafter it is just a shortened blunt tool, just able to touch the surface between the high spots.
Gavin's idea of the reversed sprocket is quite possible.

Re: how did this happen? [Re: koan58] #764894 02/09/19 12:27 am
Joined: Sep 2013
Posts: 2,007
Q
quinten Online Content
BritBike Forum member
Online Content
BritBike Forum member
Q
Joined: Sep 2013
Posts: 2,007
Quote
Gavin's idea of the reversed sprocket is quite possible.


A reversed sprocket does not change it width .
It will only change the chain alignment.

The op said he rebuilt the clutch and ... placed/ replaced
... all the original front sprocket pieces in the same order .

... but did not confirm that the 2 shims found
behind the sprocket
were necessary... for the rebuilt-clutchs chain-alignment .

Any extra thickness of the first distance piece(s) placed on the crank
Will of course,
Move the duplex-sprocket and rotor outward , closer to the timing pin .

I think the new clutch was misaligned enough
With the original front stack of parts ... to cause just enough sideways chain torque ... to cause the contact.
( a rather weak argument , but it's all I got )

Or maybe the contact marks on the rotor have been there all along... and are just now being noticed ?





Re: how did this happen? [Re: Allan Gill] #765021 02/10/19 2:12 am
Joined: Aug 2001
Posts: 4,779
Mark Z Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Aug 2001
Posts: 4,779
"and the timing pin lines up perfect with the damage to the rotor:"

Yes I see; with the point broken off the pin, it makes a wide gouge.

Originally Posted by Allan Gill
I think Mark is thinking A65, afaik all unit singles were 4 spring clutches.


Allan, I replaced clutch discs on a friend's round-barrel B44, and it was a 3-bolt clutch. I had assumed it was original, but maybe it wasn't.


Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
Re: how did this happen? [Re: quinten] #765024 02/10/19 4:55 am
Joined: Feb 2012
Posts: 65
H
Hjalte Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
H
Joined: Feb 2012
Posts: 65
okay did some messurements..
distance piece / oil seal "rider" is 7,86mm

[Linked Image]

shim between the distance piece and sprocket is 1,53mm

[Linked Image]

rotor is ~35mm
gasket is ~0,42mm

rotor jounal runout is 0,18mm
the rotor axial runout i found almost impossible to messure due to the non smooth surface

the poor pin and inspection cover has taken quite a beating

[Linked Image]

[Linked Image]


well the only thing i changed that can influence this when i did the clutch plates was the gasket... cant see this alone doing this tho.

Re: how did this happen? [Re: Hjalte] #765045 02/10/19 2:03 pm
Joined: May 2013
Posts: 5,721
Allan Gill Online Happy
BritBike Forum member
Online Happy
BritBike Forum member
Joined: May 2013
Posts: 5,721
got any photos of the sprocket? as the rotor looks like it is outboard the stator as opposed to almost flush


beerchug
Re: how did this happen? [Re: Mark Z] #765046 02/10/19 2:07 pm
Joined: May 2013
Posts: 5,721
Allan Gill Online Happy
BritBike Forum member
Online Happy
BritBike Forum member
Joined: May 2013
Posts: 5,721
Originally Posted by Mark Z


Originally Posted by Allan Gill
I think Mark is thinking A65, afaik all unit singles were 4 spring clutches.


Allan, I replaced clutch discs on a friend's round-barrel B44, and it was a 3-bolt clutch. I had assumed it was original, but maybe it wasn't.


It could be standard Mark, I haven't seen enough to be positive that they all had 4 springs or not


beerchug

Moderated by  Allan Gill, Jon W. Whitley 

Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | DVD- Manuals & Parts books
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Powered by UBB.threads™ PHP Forum Software 7.7.3