Has anyone changed out the cup and cones for modern wheel bearings.
I have a B20
If so are there any pitfalls to watch out for.
Where did you get the bearings from.
General how to do it would be nice so i am not reinventing the wheel so to speak.
not started it yet but planning to do it over the winter months.
thanks in advance
D
Likewise I have a 37 B20, similarly it's in the process of being reconditioned... I've ordered a pair of taper roller wheel bearings from Draganfly as they list them as replacements for the cup and cone set up which are the same as pre war C10. They ain't arrived yet though... so wait and see. My understanding is that taper rollers were fitted to the same hubs used on the larger B series models 37-39?
I'm still on the steep part of the learning curve with this one so happy to learn from anyone who knows better.
R.
Hi Rupert,
Thanks for the info, can send me the dragonfly part no. & a pic when you get them.
i will have a look, i didn't think of Dragonfly even though i have used them several times for bits on my b20.
Just PM me if you need any help on the rebuild, i had mine down to its component parts and completely rebuilt from a working but rough bike.
Have you got a complete bike?
Cheers
D
Mine was offered to me last year having been in someone's loft in bits since being a field bike in the '60's. Mostly complete but missing lights, footpegs, tail section of rear mudguard and other odds and ends, as you'd expect. Not too bothered about lights or total originality as I intend to build it for green laning.
I've also acquired a '39 350 ohv engine so hopefully I'll be able to pass milk floats rather than just chase them.
Many thanks for the offer of help, I expect I shall take you up on that...
I found the taper roller bearings on draganfly's site by clicking on the standard cones for the pre war C10, the taper roller alternative came up. Apparently they are an off the shelf item which is then modified. Still waiting to see...
R
Ps one part I need is the clutch lift lever on the gearbox, can anybody help?
Hi Rupert,
my footpegs are made from a length of threaded bar and 20mm black enamelled conduit plus lots of washes and nuts then topped off with some john bull footpeg rubbers.
I'm running a b21 250 OHV engine in mine at the mo as the b20 barrel cracked after relining. i got a replacement but not got round to rebuilding that engine yet.
I had to change the front sprocket to a from 19 to 21tooth as it was a bit slow topend
Have you got the bruce main smith blue parts book as you will see that b20 thru b26 have some identical parts albeit different part numbers. so when doing a search bear the models in mind that may have the same part fitted.
if you have the brown buff book check out the gearbox and front cog ratios for the gearbox they may need to be changed depending if you want topend speed or acceleration.
I used John Hemmings to retooth my rear sprocket, did a lovely job.
I found the bearings on Dragonfly
if you need to see what the clutch lever looks like i can post a pic or two. will keep eyes peeled at jumbles. even though it would not be a difficult thing to make a rudimentary version to get you going.
Keep in touch
Speak soon
D
Hi D, many thanks for the info, I've been thinking/acting along the same lines as you suggest...
Had the rear wheel sprocket rebanded by a chap near Knighton in wales.
Gearbox sprocket will also be treated to new teeth when I've done the sums re top speed to see how many teeth to have, bearing in mind the 21 tooth crank sprocket I've already got, same as yourself.
I have a 5 plate clutch to cope with the vast increase in power. Wow.
Footpegs, I have just acquired the complete set up of the right type as used on rigid B31. May need the stud/peg length altering when eventually offered up.
Rear mudguard tail section replaced with one which looks the right size/shape. It came with the number plate still showing which I looked up with dvla - said it was a Zenith!
Nice that you have a B21 engine, that was one of my options when looking for more power. I was lucky to get the engine I did really. Everything above the cylinder was missing but I have since sourced the missing bits. It has been used for racing of some sort as it had a 350 goldie piston fitted and the timing cover had been modified to take a tacho drive. Also a goldie conrod and the flywheels modified to take the larger big end.
I have the BMS parts book for 1939 the engine and it also shows the cycle parts from 1937 which as you say are either the same for other models or as equivalent parts used on C10 etc. Same parts still seem to have been used to some extent on early post war models. Also got the haycraft book which is fairly useful.
I have a length of 1/2"X1/2" steel bar ready to make a clutch lift lever. Thanks for the offer of pics, what I need to know exactly is the distance between centres of the pivot pin and the adjuster screw, and the size/thread of the adjuster. No rush if at any time you could help with these details I'd be very grateful.
Likewise keep in touch and many thanks for your input.
Rupert.
Hi Rupert,
Thats an interesting engine you got there.
The further from standard they get the nightmare they become in sourcing bits for them sometimes.
I shall take some measurements and get back to you.
D
Hi,
See attached photos
Hope these help
Regards
D
Hi,
See attached photos
Hope these help
Regards
D
Hi,
See attached photos
In the last photo the pivot pin that holds the lever in place is removed from left to right as it seems to me tapered.
Hope these help
Merry Christmas
Regards
D
Brilliant pics, many thanks for taking the trouble. Need to put a 4 jaw chuck for the lathe on the shopping list!
Still no taper roller wheel bearings from draganfly, latest update is they should be ready in February...
Best regards, Rupert.
I spoke to dragonfly, the chap who does them does a batch per month and probably next batch in feb like you say.
there is no reason why you can't do the lever with a piece of round bar, plus i did not say that the thread is 26 tpi i think standard cycle thread etc.
have you got the copper pipe from tank to carb? i made several whilst restoring mine just for practice, let me know if you need one.
have a good one
best regards
D
Hi, thanks for offer of petrol pipe, not sure whether I shall need the standard item, as the bike is non standard I may fit a concentric as the simplest option. Need to get the basics done first, next make and fit new fork bushes and spindles, then when the wheel bearings eventually arrive get the rims sorted...
Likewise, thanks and seasons greetings.
Rupert.
Hi,
i re-bushed the forks (with off the shelf oilite bushes from the bearing boys five eighth inch outside size think) and made new spindles from en16T steel from ParkerSteel.co.uk
https://www.bearingboys.co.uk/Imperial-Plain-Oilite-Bearings/AI081016-Imperial-Plain-Oilite-Bearing-Bush-12-x-58-x-1inch-42654-p
The originals were very pitted at the point where the bushes met hence there was a lot of play so decided to remake them.
the problem i found after re-bushing and re-spindleing was that the actual fork strap castings were oval-ated due to wear from the spindle so next job is that i need to oversize drill out and insert bushes in the fork straps to to reduce the rest of the play.
i was shown my friends Norton which had bronze washers between the straps and the forks (to reduce steel to steel wear) & so you can judge the tightness of the pinch nuts on the forks. i found them on eBay but would be very easy to make with a bar of oilite. will post a couple of pics of my forks soonest etc...
https://www.ebay.co.uk/itm/Girder-Fork-Knurled-Washers-for-Norton-ES2-16H-18-19-CS1-Big-4-and-others/142985398317?hash=item214a98082d:g:rPIAAOSw989bskVp
i fashioned two top hat pieces of turned steel arrangement to pull in the new bushes into the forks with a length of threaded bar thru the forks , if i find it i will take a few pics for future reference, if you want them let me know.
i found the fork friction plates on eBay too ( will try to find the supplier essex/ suffolk way ) this may be them but there are ones that offer a spacer to complement for internal diameter of the spindle.......one size fits all etc.
https://www.ebay.co.uk/itm/Triumph-Vintage-Motorcycle-Girder-Fork-friction-disc-FD085/273442117073?hash=item3faa6b95d1:g:qA8AAOSw0c9bjp1X
Thats it really at the mo....photos to follow (festive celebrations permitting.....)
Merry crimble to all
D
Hi See attached photos of the bush for the forks and the bar for the spindles.
See attached for home made top hat puller and pusher etcc...
Lastly see attched for the knurled washers in situ
regards all
D
Hi D, many thanks for your details on rebushing the forks, interesting stuff.
I also looked at oilite bushes as an easy solution but looked into it and read that oilite doesn't last as long as solid in this application? I bought some solid bronze bar and tuned 4 new bushes for the yokes as per the originals instead of being bored over Christmas. I have a press so pushing them in was no problem, then line reamed afterwards. Still got the 4 to do on the girder. I found some 1/2" en16 studs on eBay threaded unf 20tpi on both ends so am aiming to use them as a basis for the spindles (run a 20tpi cycle die down the thread to make sure it is compatible).
Likewise the plain holes and faces of the links are worn. Aiming to build the worn areas up with braze before linishing flat and re-drilling. I'm hoping that the remaining layer of braze may be a better bearing surface than the original steel/steel. BSA could have done it better but why bother on bargain basement forks?
Thanks for all your help so far and happy new year.
Rupert.
Thanks for the lead on the friction discs, I've seen some in passing but haven't really looked into this yet.
Hi Rupert,
Aha didn't know that about oilite vs bronze bushes, i went with something off the shelf.
i'll read up on that.
will keep an eye on them for wear.
i like the idea of brazing the straps and re-drilling.
went for a spin today and my mate following me mentioned my back wheel moving a bit on the way back so its off the road til i have done the bearings now.
cheers for the info.
happy new year
D
Hi, just received the long awaited taper roller rear wheel bearings from draganfly. They look like a nice job. Off the shelf taper roller bearing which looks to have the o/d ground down and an internal insert to reduce the I/d and replicate the length of the original cone. Haven't tried fitting them yet...
Rupert
Hi,
Sounds like some action at last, send some pictures if poss,
Let us know how you get on, process of changing them etc...
Cheers
D
Hi, bearing shown is marked MSB 32004X
Looking good, you'll be green laneing soon.
Have some on order from dragonfly arrived today,
looking at trial fit front wheel Saturday eve albeit a tad chilly in the workshop at the mo.
let us know how you get on will do likewise
good luck
D
Hi Rupert,
Finished fitting the front bearings fit this eve. (started Sunday)
initially had a problem with identifying two spacers under the cups in the hub but it was pointed out to me they were probably fitted later to alleviate wear in the cups and cones as they were very bad. No spacers in the parts book so home-brew after market fit.
They were that bad the grease was silver as the bearings had degraded that much.
The spindle had to be rerun with the die to clear the thread from years of abuse, after that the bearings ran on lovely.
On the dry fit the bearings did not tighten up enough so the threads on the spindle had to be cut in further on both sides equally.
After that it all went swimmingly, front wheel on and sorted.
back wheel next......the really bad one.
Keep chipping away.
D
Hi doivey, could I please trouble you for a little help?
If and when you have time could you give me a measurement for the rear wheel rim offset on your B20, maybe to the inner or outer surface of the sprocket as that would probably be easiest without disturbing anything? I'm assuming you have standard wm2 rear rim?
My rear wheel was in quite a state and I don't trust it to be true and accurate.
Also, as I've never had my bike in one piece to check, what's your opinion on the possibility of fitting a wm3 rear rim and possibly bigger section rear tyre as used on the B25 competition model? What's the clearance like with your standard set up between tyre and chain guard/ rear mudguard?
Any thoughts are much appreciated.
Rupert.
Hi Rupert,
I wil get some measurements to you hopefully over the weekend.
I did have the same offset issue with my front wheel when i had it rebuilt. i initially realised i had a problem when the front wheel kept on turning a little more after the brake was applied. On investigation the spokes were very loose and i could push, pull and turn the hub (by hand !!). i ended up giving Paul at PWWheels in Herne bay the front end forks n all. Paul sorted it lovely.
As for tyre size I'm not sure the max size for a WM2 rim but i will check my tyre and clearance to chain guard /chain etc.
K70 3.25 Front & 3.5 or 4.0 on rear.
As an aside... if you don't quite get your offset correct you can continue the threads on the spindle when you fit the taper bearings to allow for tolerance errors as i had to do this on mine last week when i fitted the front taper bearings. Also the same bearings are used in the rear also, i found that out late one eve but Dragonfly were great and swapped them and discounted the return post too. the ones i used are 29-5700TR & 29-5702TR
I also found a spacers in my hubs too to offset the wear of the cup and cones so look out for those too, they are not in the parts book.
Speak soon
Doive
Many thanks for that, all interesting stuff re the bearings.
The usual rule with tyre sizes is up to 3.5 on a wm2 rim so if there is enough space with the mudguard and chain guard to accommodate a 4.0 inch tyre I would fit a wm3 rim to suit it.
The parts book shows a wm3 rear rim for the B25 competition model so I'm hoping there won't be a clearance issue?
Many thanks for offering to do some measuring.
Regards, Rupert.
Hi, I've just had an afternoon fitting the taper roller bearings from draganfly to the rear hub, which we've talked about earlier on this thread.
Outer races fitted perfectly ok.
A few issues with the threaded sleeves inside the bearing inners -
The internal counterbore seemed to be binding slightly on the peaks of the spindle thread, overcome by boring the hole out slightly.
No problem with o/s bearing inner.
N/s bearing inner held the brakeplate a good 1/8" too far outboard. To overcome this meant shortening the inner sleeve in three places from its inner end; the outside shoulder, the spigot and the internal thread by counterboring it deeper.
The other issue which I havnt rectified yet is that the felt seal holder assembly on each side is prevented from going fully home in the hub as it hits the inner bearing race first...
May see if an off the shelf oil seal is available as a replacement.
Regards, Rupert.
Hi Rupert,
Regards the problems you had with the binding i overcome by increasing the thread length on the spindle and running a 20tpi tap down the bore a the thread ran out when i looked at it closely. this is equivalent to you boring out the bit that you did.
i ended up running a die down the spindle too as the thread needed redefining to fit the new bearing inner as it had a severe tight spot on both sides.
regards the felt seal holder mine went in perfectly flush with the hub and the bearing inner poking thru so it was adjustable. i would check that your outer races have gone right into the inner shoulder in the hub..
Regards the tyres and rim offsets
i have checked and i have a 3.5 x 19 on the rear.
the offset from the hub edge to the rim is 25mm and should be equal on both sides as the rim is laced to the hub on both side and the drum riveted onto it. unlike the front where its laced to the brake drum outer.
the distance from the rim to the chain guard is 22mm
the distance from the tyre outer to chain guard is 10mm
the distance from the tyre to the inner rim of the mudguard is 25mm.
may be worth going with a smaller but more knobbly tyre if you going to green lane it.
I have some pictures to upload which i shall hopefully do at work tomorrow time allowing.
if you need more measurements, let me know, hope this info helps.
Keep chipping away.
regards
D
Hi doivey, very many thanks for taking the measurements. It seems that a wm3 rear rim should be ok but a full size 4" rear tyre maybe a problem. Possibly a smaller section tyre instead but I'll look at that when the time comes.
Since my last message after fitting the taper roller bearings to the rear hub I've done a bit more research and head scratching. I reckon the brake side cone is holding the brakeplate too far outboard by maybe 1/16" so I'll look at turning back the outer shoulder on which the brakeplate sits.
Re the oilseal issue, the bearing outers are fully home in the hub as I used a press to fit them and could tell exactly when they seated on the shoulders in the hub. The seal assembly is definitely resting on the end of the bearing inner, with the sleeve protruding through the seal as it should. Resting on the bearing inner in this way means the seal cups are level with the ends of the hub, whereas they should be positioned about 1/8" below the ends of the hub, below the level of the internal chamfers in the hub ends.
Nothing that can't be fixed.
Regards, Rupert.
Hi Rupert,
Its good to hear you are getting around the snags. i finally got the photo to upload so here it is.
the hex bar is across the hub rim.
the offset photo in post above is upside down, bear that in mind. sorry.
these may be upside down too. info in photo title.
if you need more let me know.
D
Many thanks for the pics, that's excellent, above and beyond the call of duty!
I've ordered rims and spokes, wm3 19 for the rear, WM1 21 for the front, both as per standard on B25. Thanks for confirming that that shouldn't present any problems.
Rupert.
Hi Rupert,
Eventually got out for a spin after changing both wheel bearing sets and it runs lovely and smooth now.
Definite recommend the Dragonfly replacement taper bearings.
Regards
D
Hi doivey, thanks for the feedback on the bearings, looking forward to being able to rotate mine...