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#833785 12/19/20 1:56 am
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Hi all,

I'm having two issues with the gearbox on my 1949 M21.

1. It's getting increasingly hard to find third gear. It was always the hard one, but on the last ride I missed it more than 50% of the time (over shifted). It feels like the detent is really slight so I can only feel it if I really concentrate.

2. When I do find third, it feels like the clutch is slipping when I release it. There will be minimal power transfer for a second of two (you can rev and nothing happened), then it just kicks in suddenly, with a bit of a jolt. This happens on up and down shifting, and only going to third.

I thought the primary may have been full of oil from wet sumping, causing the clutch to slip, but it's fine.

Any ideas as to what could be causing these issues?

Thanks,

Luke

Last edited by Howley; 12/19/20 1:58 am. Reason: Changed the word '[***]' to 'jolt' to prevent censoring
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I'll be interested in hearing what the experts have to say because my M21 transmission has been doing exactly the same thing for years. I've just been putting up with it, but it's a pain.

Shifting from second, it will engage third about 1 out of 10 times. Shifting down from fourth to third, it shifts perfectly. The little ratchet mechanism on the shifter is tight and timed right ... you can see and feel (shifting by hand with the cover off) that whatever is happening wrong is happening down inside the transmission ....

Time to get it out of the bike and onto the bench, I suppose! Maybe your situation is what I've needed to kick myself into action on this ...

Lannis


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Howley : anything to help a fellow sand hopper ( im originally from Kal , love the skimpies ha)

you can pretty much guarantee from what you have said that the selector shaft cam are shagged out on the crest of the part where 2nd 3rd are selected ,,,this lets the follower have to much clearance and you will kind of miss 3rd and go straight to 4th when changing up from 2nd .and visa versa ...sound familiar ?

that is where they always wear Lannis ....only solution is either build up the cam ( i dont recommend this) or replace the entire selector (replace is best)

step 1 gear box out...you can just pull the cluster but honestly to much other stuff worth doing while you have it out. Besides the only way to check all sorts of other stuff (too much to go on about here ) is on the bench were you can see it ...its a painstaking job but very satisfying when its all in order . They are an excellent piece of engineering

i have mucked around with these M series boxes a lot have done dozens of them ,,,dang people all round the country sent them to me (gee thanks)

i will try to find a pic of the selector and cam ......

https://www.britcycle.com.au/wp-content/uploads/2017/02/DSCF1895-416x312.jpg

you can see where the area i am talking about is ....its the apex of the cams

it will be obvious where the wear is when you pull it

a better pic showing cam follower sitting right on apex im talking about

https://www.trojanclassics.com/assets/alt_2/66-3288.jpg?20200707032639


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I'll get out the Manual and see how to get the box out of the bike ... looks like a right bugger of a job compared to the simplicity of most stuff on this old sidevalve; oil tank out, etc ....

Lannis


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Originally Posted by Lannis
I'll get out the Manual and see how to get the box out of the bike ... looks like a right bugger of a job compared to the simplicity of most stuff on this old sidevalve; oil tank out, etc ....

Lannis

nah its pretty straight forward real easy if you can get it up off the ground somehow .......probably take 4 hours with swearing breaks ...if you want a difficult one try the semi unit plunger box whole motor needs to come out


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Well let's get to work then, Shaun's been taking the mickey out of me for 12 years because I haven't sorted out the M21 transmission third gear.

I have a spare M20 transmission so let's practice on that one. I was at MidOhio with Bonzo and was talking about my transmission trouble, he got up from his camp chair, went to the swap meet, and came back in an hour with this transmission:

[Linked Image from photos.smugmug.com]

So let's do it. I took off the small square cover:

[Linked Image from photos.smugmug.com]

Then took off the outer cover where the kickstarter and shifter shafts come through:

[Linked Image from photos.smugmug.com]

And this is what's under there:

[Linked Image from photos.smugmug.com]

What's the order of disassembly? The shifter ratcheting mechanism, then the pinion gear, then the recessed mounting screws? Thought I'd ask while I had you guys here ...

Lannis


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biggest trap is if you dont pull the speedo drive shaft ( the 1/2 nut you can see on top of the inner cover) first ,, you need to undo teh small screw FIRST (the one you see above the bronze bush !/4 BSW for a few turns then long 3/16 plain section on it that does the retaining (think turned down grub screw) ...if you dont take that lock screw out ( its quite long but only a few turns of thread you wont be able to pill the bronze speedo drive spindle bush ....i have seen lots where morons havent pulled the screw and then wonder why it wont come apart so they end up forcing things and rooting it

get hold of a parts book and you will clearly see what im talking about

apart from that into it , its not rocket science ....the selector mechanism is a confusing damm thing but that wil come off with the inner cover as a unit take photos ! try to keep the selector unit in one piece if you can , easy when u have done a few but oh man when u havent ya know

dont lose the small detent spring loaded pins .....one small one that is supposed to help keep selectors neural (behind selector u can see) and a larger one behind tHE cover which goes into the 1/2 cog which drives the selector shaft i put a pic of on previously

seriously get a parts book pic that will save you a lot of head scratching at reassembly time

i can help talk u through reassembly when you need

honest man its not that hard


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1. Take photos - CHECK
2. Look out for little springs - CHECK
3. Take the selector clockwork out in one piece - CHECK
4. Pull speedo drive shaft first - CHECK
5. Get out the parts Manual - CHECK

I've got to make a few goodies for our family Christmas get-together tomorrow so not sure if I'll be able to put in a session today, but ...

Thanks!

Lannis


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Get a new oil seal on the way , also figure out how you are going to get bush , or get made bush for top gear 7/8th id , you can get bushes ready made at the bearing suplier but they must be reamed when fitted ( the long bush the main shaft runs in for final drive ) you WILL need both ! ....Replace both bearings while you are in there ....they are an easy size to find just at a bearing supplier ...way cheaper that way ,,,you will aslo need a selection of shims , 7/8 id from memory for setting working clearance on mainshaft etc


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Originally Posted by Ignoramus
Get a new oil seal on the way , also figure out how you are going to get bush , or get made bush for top gear 7/8th id , you can get bushes ready made at the bearing suplier but they must be reamed when fitted ( the long bush the main shaft runs in for final drive ) you WILL need both ! ....Replace both bearings while you are in there ....they are an easy size to find just at a bearing supplier ...way cheaper that way ,,,you will aslo need a selection of shims , 7/8 id from memory for setting working clearance on mainshaft etc

Oil seals I know, shims I know, bearings I know ... but how does a regular guy deal with "must be reamed when fitted"? That's the way my BSA A65 bottom end goes in, but that's a specialist job in a shop with proper fixtures. Surely the every-day go-to-work guys that ran 90% of these bikes didn't send their gearboxes off to be done?

Lannis


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oil seals arnt a standard size .....i got some which were correct iD and had to skim maybee 20 thou off od made
up 10 cause it was such an act you wont be able to fit a standard od off the shelf seal it will be way to tight on od

no the reaming isnt a big deal you are only taking a thou or so out to compensate for the bush collapsing a little when pressed in ...just wind a hand 7/8 reamer through it .........you can hire one for bugger all .....the clearance is on the shaft which is maybee 2 thou under 7/8 u know built in clearnce IF the bush id is exactly 7/8 .......i relieved the od of the off the shelf bush so it wasnt such a tight press fit heated up the pinion and squezzed it in with a vice and locktigh easily done with 220 paper and time

at a pinch just get a peice of round dowling wood , say 3/4 diameter and glue a few turns of 220 grit wet and dry paper to it and kind of work it a bit and keep checking for nice working clearance against main shaft till u are happy (but i didnt say that or we will get all sorts of chime ins about oh no no no it must be done like this or that ..dont worry about exact reamed size you are after working clearance

its nothing like the BS talked about line reaming ect .TS main ect ....easy to do just with hand tools !


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So, unbuttoning the inner cover - the shop Manual says "4 screws" but there are five; 3 cheese-head screws and two hex-head bolts ...

[Linked Image from photos.smugmug.com]

and off it comes. There was no oil nor any trace of it in this gearbox, but there's no rust and everything looks to be in pretty good shape.

[Linked Image from photos.smugmug.com]

Since the mainshaft still has some bits on the drive side, it stayed in the case ...

[Linked Image from photos.smugmug.com]

Things look pretty good to my unpracticed-on-transmissions eye ...

[Linked Image from photos.smugmug.com]
[Linked Image from photos.smugmug.com]

In order to complete stripping it, I need to take these clutch/drive things off the primary side, but the Manual is vague on the subject:

[Linked Image from photos.smugmug.com]
[Linked Image from photos.smugmug.com]

Thanks in advance!

Lannis


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Originally Posted by Lannis
Oil seals I know, shims I know, bearings I know ... but how does a regular guy deal with "must be reamed when fitted"? That's the way my BSA A65 bottom end goes in, but that's a specialist job in a shop with proper fixtures. Surely the every-day go-to-work guys that ran 90% of these bikes didn't send their gearboxes off to be done?

Lannis

Depending on the situation, for the home shop lapping can be a good way to go. A transmission bushing would be a good candidate. In the end, the bushing would still be round and not barrel shaped, given a more consistent clearance.... spreading the load and retaining the oil.

You could do some reading on Time Saver Lapping compound. They have some in different grades for soft metals and hard metals. It won’t imbed itself into the bushing. I have a box of it containing the different grades of both varieties. 8 small tins. Don’t know what they sell for today. Handy stuff and in the home shop, the little tins will likely last a lifetime.

Ps... another good method is ball sizing. Have a look at the new Triumph cam bushing setup (I think from CBS).. it gives an example of how it works. A search will give you the name of a US company that specializes in manufacturing the balls. Worth a search and reading some of the info there. If you can’t find it, let me know... I have the link saved elsewhere.

Last edited by Cyborg; 12/22/20 4:59 pm.
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Lannis: what you have there is the early version of that M box , you can tell the deference by the size of the selector fork carrier shaft ...compare that size to the pic i posted in the beginning of this thread , they are NOT interchangeable

also the box you have shown doesn't have the oil seal they have s slinger system with a sort of helical grove which is supposed to keep the oil n the box ,,good luck

Did you say something about this is just a practice one and not the one in the bike you are going to fix?

but yes the one u have stripped does look in good nick

pretty easy really eh


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Lannis asked :
"In order to complete stripping it, I need to take these clutch/drive things off the primary side, but the Manual is vague on the subject:"

if you mean the selector pauls or is that pawls (the bits the selector fork moves) in your 3rd pic from the bottom no you dont have to just list the lay shaft and gear cluster and the selector shaft out as "one piece ) ie both together

once again be carefull of the spring loaded detent behind the actuator half pinion

if you mean the mainshaft shown in last 2 pic yes you do because there is a retainer collar than screws onto the final drive pinion and secures the sprocket ...you cant remove this pinion without releasing that collar


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Originally Posted by Lannis
Since the mainshaft still has some bits on the drive side, it stayed in the case ...

In order to complete stripping it, I need to take these clutch/drive things off the primary side, but the Manual is vague on the subject:

[Linked Image from photos.smugmug.com]

Thanks in advance!

Lannis

Sounds like this tranny may not be a parts tranny for my road one. The grease pencil note on this one said it was for a '50 - '54 but that may or may not be right, just what someone thought. Mine that needs fixing is a '55.

The thing I'm trying to do is get the collar with two grooves in it in the picture off of the input shaft so that the shields behind the clutch and the final drive sprocket can be taken off .... ??

Lannis


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your 55 box will have the selector like this one

https://www.trojanclassics.com/assets/alt_2/66-3288.jpg?20200707032639

see how the shaft is clearly a smaller diameter to the one u have

"The thing I'm trying to do is get the collar with two grooves in it in the picture off of the input shaft so that the shields behind the clutch and the final drive sprocket can be taken off .... ??"

ah ok thats the oil slinger it sits on the end of the top gear pinion not threaded or keyed , the clutch backing plate is splined to the pinion shaft



would i suggest 2 large screw drivers sharpned down to a point or a couple of old wood work chisels ? nah not realy but hey your call if u want to try that .(dont stuff the pinion spline) ....dont force it too much heat the *itch up a bit first not too much just say hot air gun hot ....it will move


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Hi
You will need to pull the clutch centre from the tapered main shaft, it has a thread to take the puller , but in this situation you miaght be able to use a split collar puller to get behind it once the clutch rear plate is off

John

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Originally Posted by chaterlea25
Hi
You will need to pull the clutch centre from the tapered main shaft, it has a thread to take the puller , but in this situation you miaght be able to use a split collar puller to get behind it once the clutch rear plate is off

John

Whew, been a couple weeks of Christmas and New Years and a lot of other work getting done and re-doing a chainsaw fuel system and ... and ....

Anyway, back to the tranny now.

Successfully pulled the clutch center with a standard gear puller and a bit of tapping, pulled out the main shaft, then heated the case and tapped the big Hoffman 135 bearing out of there ....


It's completely seized up, won't move at all, probably the ball race is corroded, I'm soaking it in oil now because I just want to free it up so that I can test-assemble the transmission. I want to learn to assemble it, and bench-test the shifting so I can learn how it works, so won't install new bearings and oil seals at this point, just dry-assemble and shim and time it, oil it enough to work it, and once I'm ready to tackle the one on the bike, just set this one aside as a spare, leaving a tag on it that it needs bearings and seals so's I don't forget ....

SAM_1038.JPG

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Get a 2RS replacement bearing & pull the inner off.
Helps slow the flow
These boxes are a lot of "fun"
If I knew Ignoramus was an expert, I would have sent him mine too .
M series had the heavy weight box for hauling side cars & B series got the medium weight box for speed.
AFAIK the gears , mainshaft & the ratchet pinin interchange and that is about all.
There are 4 different shift forks and as well as the pin size and std or roller pins.
The distance between the actual fork and the pin also varies.

I had a good box that I stuffed listening to "knowledgable" others who said to run liquid grease to prevent the oil spewing out.
That might have been fine for a 1 hour putter around the foot hills but a lot of 400 to 600 km runs totally stuffed my box

I thought I knew what I was doing & built up a best of bad bits box for the the 2019 BSA national.
Got 1/3 into the first run & the box spat the dummy

Add to that the hand change box is very similar and they came in light & medium weight as well.
The gears interchange with hand change boxes, but that is it .
So you have to be really careful buying parts because very few vendors actually know what they are selling.
I used to get my bits from an M20 only specialist who has closed down so now it is Russell Motors in the UK .
Down side is they are only open 4 days, open late & close early but LEs is over 80 so you can forgive him for that.
Other problem is it calling orders, phone orders or snail mail only .
OTOH prices are good, still lots of NOS parts or pattern parts that are dimensionally correct .

And despite som who lurk here that like to measure to +/- 0.00001" , these boxes were designed to be fixed on the side of the road with a hand full of sand & a bent stick.
The fact there are so many around running original boxes some 80 or more years latter is a testiment to their robustness.

In the technical section of the WM20 forum web page you will find a wealth of tips & tricks .


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Trevor Said :

"If I knew Ignoramus was an expert, I would have sent him mine too .
M series had the heavy weight box for hauling side cars & B series got the medium weight box for speed.
AFAIK the gears , mainshaft & the ratchet pinin interchange and that is about all.
There are 4 different shift forks and as well as the pin size and std or roller pins.
The distance between the actual fork and the pin also varies."

well i never said i was an expert just that ive done a few.

In some of the earlier ones the gears might be the same number of teeth (other than close ratio boxes) however the gear MODUAL is different, meaning that an early gear wont mesh with gears in a latter box. (domt ask me years ive forgotten

the main shafts can also be different lengths depending on year ie how much sticks out of the box

some also have longer selector shafts ( still haven't figured out which box the long ones fit but my best guess would be the "transitional box" made for only like 2 years between the WM box that you have and the latter 50s version .(47/8- 50?)....try finding bits for those! The early ones like WM have a larger diameter than the ones in Landis"s pic

THe selector shaft assy does have 2 different cam grooves you are right , straight cam follower pin ( 1/4" ) or roller follower (3/8 ) BUT the entire assembly will interchange dimensionally they are the same.........no idea what year that change happened.

Then there is the oil seal or no oil seal version .........man it goes on

but yep using grease in those is a real bad idea!

Last edited by Ignoramus; 01/10/21 8:18 pm.

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Originally Posted by Ignoramus
Trevor Said :

"If I knew Ignoramus was an expert, I would have sent him mine too .
M series had the heavy weight box for hauling side cars & B series got the medium weight box for speed.
AFAIK the gears , mainshaft & the ratchet pinin interchange and that is about all.
There are 4 different shift forks and as well as the pin size and std or roller pins.
The distance between the actual fork and the pin also varies."

well i never said i was an expert just that ive done a few.

No no you ain't going to get out of it that easy
Preparing a couple of cartons to send your way as I type smile

Last edited by BSA_WM20; 01/11/21 4:50 am.

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ive been selling off loads of that surplus stuff no way i want more ...( and man it does sell fast and for reasonable $ as well) .......i think 4 fully rebulit M boxes should be sufficient spare gearboxes for 1 bike


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All right, back to the M21 gearbox.

I freed up the mainshaft bearing, and it spins freely and has no play. It's plenty fine for reassembling the box for practice.

So I heated the case and drove the bearing back in ....

View from the outside ....
[Linked Image from photos.smugmug.com]

and inside of the box ...

[Linked Image from photos.smugmug.com]

Then I slide the pinion sleeve back in ... Inside
[Linked Image from photos.smugmug.com]

From outside ..

[Linked Image from photos.smugmug.com]

Now it gets tough. I have this book, which I thought had what I needed in it, but it doesn't.

[Linked Image from photos.smugmug.com]

The ONLY drawing it has of the gears and shafts in the gearbox is this:

[Linked Image from photos.smugmug.com]

and there's no exploded view, no descriptions .... it says things like "If a new ballrace has been fitted to the top gear pinion, make sure that the Oil Flinger washers are correctly positioned." No picture of an "Oil Flinger Washer" and nothing about what "correctly positioned" is.

I have the Russell Motors M21 gearbox catalog, but it does not have an exploded parts view, just the few parts that they sell, and there's nothing to key the part number on this page to the name of the part, like "oil flinger washer" or "locknut washer".

[Linked Image from photos.smugmug.com]

I don't want the folks here to have to be my personal walking talking Parts Manual, so where can I get a complete exploded view with part names that will help me relate the parts in my hand to the limited word descriptions in the Shop Manual?

I'm gonna need it!

Thanks!

Lannis


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Sorry to be the one to tell you , but out the bearing comes again

there are 2 oil flinger washers .one on each side of the bearing 65-3509...the sprocket side of bearing ,it is dished so it rotates with the bearing inside the cover recess and is firmly captured by the end of the sprocket against the id of the bearing ....u will figure it when u see one

the other is 24-1225 gearbox oil retaining washer .......this goes on the inside of the bearing facing the main shaft etc it is also dished so it can rotate ....if you dont have these in place you will have like 2 mm endfloat on main shaft and that will bugger the selector ability

ok those numbers are off a latter box than yours with an oil seal but i dont thing BSA changed the layout or washer sizes

sorry but you did ask

yours has that "treaded.grooved" oil pusher back thing you had problems getting off but im pretty sure it also has the 2 flinger washers ...yep its a bran teaser


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Originally Posted by Ignoramus
Sorry to be the one to tell you , but out the bearing comes again

there are 2 oil flinger washers .one on each side of the bearing 65-3509...the sprocket side of bearing ,it is dished so it rotates with the bearing inside the cover recess and is firmly captured by the end of the sprocket against the id of the bearing ....u will figure it when u see one

the other is 24-1225 gearbox oil retaining washer .......this goes on the inside of the bearing facing the main shaft etc it is also dished so it can rotate ....if you dont have these in place you will have like 2 mm endfloat on main shaft and that will bugger the selector ability

ok those numbers are off a latter box than yours with an oil seal but i dont thing BSA changed the layout or washer sizes

sorry but you did ask

yours has that "treaded.grooved" oil pusher back thing you had problems getting off but im pretty sure it also has the 2 flinger washers ...yep its a bran teaser

All right, boss, I followed orders, heated the case back up, and drove the bearing back out and now I can't figure out why I did that.

The bearing measures perfectly symmetrical, i.e. it doesn't matter which way it goes in. Plus, when I first took it apart, there was nothing between the bearing and the case; the bearing drives all the way into its seat in the case and there's nothing else.

Here are the only two washers/spacers that were near the bearing:

[Linked Image from photos.smugmug.com]

So are these the "oil flinger washers"? Which one goes on which side, and do they both seat directly against the ID of the bearing?

Boy howdy, I really need an exploded diagram that shows these things .... maybe the M20 site has one? Hate to keep bugging you one washer and one part at a time - there's hundreds of them!! Thanks!

Lannis


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Lannis, have you looked at all the gearbox stuff here?
Andy
http://www.wdbsa.nl/technical_section.htm


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Lannis its no "bugging" at all i enjoy helping someone if i can with one of very few things i know a bit about!

Remember i am only going by the oil seal version of that box , but think your non oil seal version would also be the same lay out

the washer closest to the bearing is a flinger by the look of it however it is the one that goes OUTSIDE the bearing going by its diameter so you are missing the INNER ONE ,check this by the diameter of the flinger you have being just slight clearance on the step down part of the case sprocket side of the bearing !

the washer with the tangs is the one that locks the sprocket retaining collar ...a tang gets bent into a slot in the collar

it wasn't a waste of time drifting the brg back out im 95% sure you are missing a flinger on the inside side of the bearing ,and if the one you have in you pic was on the inside it had been misplaced .... its been a while since i did one of these boxes but im pretty sure the flingers are different diameters hence the different part numbers i gave you above somewhere BUT practice make perfect right

yeah you do need a GA drawing ... someone must have a digital one here they can post for you ... maybee make a new thread asking but keep this tread live so we can continue walking through the job . specially when you get to the actual box you want to fix


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OK, so I'm starting to understand ... there was no washer between the bearing and the case where the bearing seats, Neale Gentner's writeup (from the M20 site, thanks Andy!) on the gearbox says that that washer "is often missing" from the gearbox, and mine was. (I think you showed 24-1225 for that part, he shows 24-4225?)

Since this is going to be a "practice" and "parts" gearbox, I think that I will "turn down" the OD of the bearing so it's an easy slip fit into the case, make a washer to take up the space that the proper one should have, and go ahead with assembly - before anyone would use this gearbox, the bearing needs to be replaced anyway, so I will use it for practice assembly and leave a tag on the outside when I'm done as to what needs replacing to put it on the road.

Back in a bit!

Lannis


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https://draganfly.co.uk/wp-content/uploads/content/BM_gearbox.gif

shows the GA but remember its an oil seal version of what you are working on

NOTE teh placement of parts 10 and 101 .....gave you the part numbers of those earlier

PS
personally i wouldn't go wrecking a good bearing just to save a few minutes taking it in and out a couple of times and potentially laying a mine field for any unfortunate who ends up with the box ... tags can come off ya know ,,,just saying


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Originally Posted by Ignoramus
https://draganfly.co.uk/wp-content/uploads/content/BM_gearbox.gif

shows the GA but remember its an oil seal version of what you are working on

NOTE teh placement of parts 10 and 101 .....gave you the part numbers of those earlier

PS
personally i wouldn't go wrecking a good bearing just to save a few minutes taking it in and out a couple of times and potentially laying a mine field for any unfortunate who ends up with the box ... tags can come off ya know ,,,just saying

I don't think it is a good bearing ... it was seized up solid when I took it out, soaked it in penetrant and then oil, then slipped it onto an expanding collet, tightened it up, and used a strap wrench on the outside and it finally broke loose - a lot more cleaning and it FEELS good in the hand when you turn it, but I wouldn't use it on any bike of mine ...

Lannis


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Well your call but you can get very good Jap Nachi bearings that size ....i payed only around $40 NZ dollars for those so what ? $25-30 US to not compromise an otherwise good box ...sounds like a no brainer to me

just out of interest those boxes sell for good money if they are working and complete , i have just sold one for $800 NZ ,( $500US?) the guy didnt even blink! , admittedly that was a rebuild box though


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Please lannis put thtabeaing back in by all means
Wait for the hottest day of the year then take a test ride through Death Valley and don't take any water with you because riding an air cooled engine you won't need water.


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OK, I'm back. Thanks Lannis for picking up the baton.

I got the 'box out and this is what I've got. The apex you were talking about Ignoramus (to my untrained eye) doesn't look that bad.
Apex picture

When it's working (which let's be honest is most of the time it's on the bench), it sits here, although it seems to often get stuck like this on the way up and like this on the way down.

Additionally there's no perceptible end float of the selector in first, a tiny bit in second (under a mm) but about 3mm in 3rd.

Any ideas or observations?

Cheers!

Luke

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just from pics cam looks ok ........

I would try disconnecting the radius arm that links the "saw tooth selector mechanism" to the "tang" on the end of the quadrant gear that you cant see inside the inner cover ....

it will be trial and error but adjusting the length either more or less will cause greater or lesser travel in the selector forks (in one direction) which control the movement of the actual pawl that engages with the gear you are trying to select

have a play with that and report back ......it IS trial and error ok ....try to note how many turns you add or subtract from the length from what it is now ...there will likely be a "sweet spot" where you get all the gears Make sure you dont loose the ability to select neutral in your zeal to concentrate o the offending gear ...it must obviously select all gears including neutral ... ideally in neutral there should be the same gap between !st and 2nd pinions and pawl ie clearance between each side of the pawl/gears im on about ...but hey as long as all the gears select and neutral is at least there you might be good to go ...we will see ..its a balancing act at this stage


. dont get hung up on the end float t issue just yet ...but do report on how much end float you have in the mAIN shaft ...excessive end float on the main shaft makes adjusting theses boxes a pig and sure wont help your clutch travel

one thing at a time bro


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Thanks mate, that was my thinking too, in my mind I should have to make that link longer.

Main shaft end float is good, it was carefully shimmed with a clock and is 'barely perceptible' as per specification.

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Originally Posted by Howley
Thanks mate, that was my thinking too, in my mind I should have to make that link longer.

Main shaft end float is good, it was carefully shimmed with a clock and is 'barely perceptible' as per specification.

dude its a balancing trial an error thing .......let us know how u get on .... good one with main shaft end float , dont get that right FIRST you are wasting your time


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