I want to replace my front wheel bearings they are size 6204 fairly standard size and cheap. My question is should I fit the original type bearings which didn't have shields or go for rubber sealed rs type. As far as I can tell the external dimensions will be exactly the same is there any downside to shielded bearings
It's best to go for sealed bearings to keep the grease in and everything else out - they work in exactly the same way as the standard bearings. If you go for double lipped bearings (seals on both sides), you can't re-grease them at a future date. In principle, you can re-grease single lipped bearings (seal on the outside). Personally, I would go for double lipped because it's unlikely you will need to re-grease the bearings.
Thanks I will order the double sealed bearings :)
Received my shiny new wheel bearings and cracked on with removing the old ones. I put all the parts on the bench as they come out of the hub and I realised I was missing the LH bearing dust cap part no 37-1481 thought I had mislaid it but it's definitely not there.
Is it a vital part as I am fitting bearings with double seals I hope not because it seems to be out of stock every site I could find on Google. If it is needed as a bearing spacer could I simply modify a repair washer as they look approximately the right thickness.
Just spotted a similar bearing dust cap for a Triumph T100 hub part no 37-1237
https://www.ebay.co.uk/itm/112919789383?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=3yrk-B-IS5-&sssrc=2349624&ssuid=Bzm2JMbPRXO&var=&widget_ver=artemis&media=COPY
as far as I have read the T100 hub is the same as fitted to the 1969 B25. Can anyone tell me if this part is compatible or even at a pinch can be filed to fit.
Although it is referred to as a dust cover, it is also designed to retain the LH bearing in place under the circlip. Without the dust cover, the bearing and hub could move sideways 3/16".
The BSA TLS hub was basically a copy of the Triumph TLS hub. Although the Triumph dust cover was part W1237 (37-1237), the corresponding BSA cover is actually listed as part 42-5820. However, as far as I can see, the parts should be interchangeable.
Thanks Spaceman I will order the spacer fingers crossed it fits though the dimensions seem right at 1 and 3/4" external, 3/4" internal.