Burman CP Gearbox Rebuild

Rebuilding a Gearbox from a 1948 Matchless G80.

[@joaotouzet2755]

Very nice and very useful thanks

[@MrMrmicah]

Legend

[@thra5herxb12s]

A real pleasure to work on these boxes but you have the oil seal back to front.

[@gentlerowdy]

beautiful dint know u were such an artist roop

[@Vintage-Cycle]

Thanks Atul.

[@coolhand1964]

Mate if I can make a suggestion, get some short length of 90° angle iron and fabricate a stand to mount the main section of the gearbox in on the bench, it makes life sooo much easier for assembly-disassembly. I mounted the stand on a board and just sit the whole lot on the bench when I need it.

[@maurocasagrande5213]

ottimo lavoro, sei in gamba.

[@michaelkerr8987]

That was sooooooo helpful !! Thank you.

[@glaicogobbo4046]

I really liked the comparison between the seal and its protections at the pinion outlet, the old type of felt sealant and the modern synthetic rubber. If they do not manufacture more in these measures. in the last case, it is not difficult to make a mixed felt retainer with leather (suede) embedded in pressure, protected with super polished and sliding steel washers. If one day you can show the seal between the pinion output and the primary current that activates the clutch, where there was always a little dirt due to there being no sliding contact retainers.

[@Vintage-Cycle]

Thanks for the input 👍. Will keep in mind on next rebuild.

[@andycossies8037]

Input/output shaft oil seal is installed the wrong way around

[@christidmas3995]

Also better to put in vice to hold gearbox in place for ease of assembly.

[@samsente6609]

Thank you for sharing,is it a 1938 Burman gearbox?

[@Vintage-Cycle]

1948

[@Mr851Tricolore]

Thank you so much, it's very helpful! A question about the clutch: I have a failed kickstart lever on my Vincent Comet, it goes down without engaging, so probably it is a problem with the clutch mainshaft, that may have the splines worn. Do you have some video about dismantling the clutch and extracting the mainshaft? Any suggestion will be welcome. Thanks again :-)

[@Vintage-Cycle]

Check the kick ratchet gear in the cover.

[@Mr851Tricolore]

@@Vintage-Cycle thanks

[@shaneboyce9392]

Would anybody know where I can get some replacement gears for a 1929 ajs 500cc side valve bike ,3sd suicide shift?lovely work here buddy

[@Vintage-Cycle]

Check AMC spares online.

[@ajazkhan2492]

Good

[@Vintage-Cycle]

Thank you.

[@OLDMADRASMOTORCYCLES]

Hope it's of a G3WO gear wheel teeth numbers are of early models

[@christidmas3995]

Enjoyed your video.Rebuilt my 55 AJS gearbox way back when.Just have the low music in the background.The music is cutting in snd out.Too jarring to listen to.All the best.

[@Vintage-Cycle]

Thank you so much.

[@eierblinker]

Question: Whats the tolerance betwenn the mainshaft sleeve gear bush and the mainshaft? I own a BAP Gearbox (filled with grease) and i can "feel" clearance at the shaft / bush.

[@Vintage-Cycle]

don't know off the head now, but check the working manual, it will say all that.

[@victorvilaca6079]

EXCELLENT PRESENTATION I would like you to find out where I can buy the seal assembly and the bearing. In Portugal there is not. thanks

[@Vintage-Cycle]

From England. Thats were i got them.

[@victorvilaca6079]

good afternoon Is it possible to give me the email address of the store where you bought it?

[@ad-si4bq]

Try dragonfly they work with Ariel mostly but the gearboxes were similar or same and they have that seal kit​@@victorvilaca6079

[@matthewnaylor4412]

What lubrication is used inside? Silly question but do they require oil or is it greased? Is that a drain plug underneath it?.

[@coolhand1964]

AJS recommends sae-50 oil where as Ariel recommends fluid grease. The Australian Oil Company 'Penrite' has a fluid grease that is actually marked 'for Burman gearboxes' on the label. I have replaced the oil in my Matchless with the fluid grease and the result was excellent. It needs to be heated in a saucepan then poured into a fat funnel, then worked through the gearbox with the kickstart lever (open the clutch by cable tying the clutch leaver hard against the handlebar) until about 1.5 cartridges are in the gearbox. The result is smoother gear changes, quiet running and a reduction in leaks around the gearshift and kickstart axles and the mains haft seal. To remove it, go for a ride and warm the box up, then fill the box to the top with distillate. Go for a short ride and mix it all up, then drain the lot while the box is still warm, leave it a few hours if you can. It's all messy work, so have a roll of paper towels ready and newspaper on the ground to keep the tree huggers happy, but we'll worth it in the end. I did not changed the grease for 5 years until I decided to change the mainseal.

[@thra5herxb12s]

Could you not just have fitted a modern 6206 RS bearing for the mainshaft. It has rubber seals and costs $5 the Hoffman one has no seals and costs $70.

[@Vintage-Cycle]

Possibly, I was not aware.

[@davethomas3493]

That bearing has an ID of 32mm instead of 32.5. Does it still fit ?

[@zurdoremi]

who reseals Burman steering boxes in the US ? Mine is leaking.

[@Vintage-Cycle]

Not sure, but they are not too hard to rebuild yourself.

[@davidbodycomb666]

@@Vintage-Cycle I use Penrite semi-fluid grease - works a treat