Velocette Kickstart Oil Seal - BK4

Velocette Kickstart Oil Seal

Written by: Mark Newsome | Posted on: | Category:

Trying to make these old British motorcycles drip 'less' oil is certainly one thing that people have been trying to do for years. A common place for the Velocette to weep oil from is the kickstart bearing housing, part number BK4.

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The oil level in the gearbox when topped up to the correct level, means that when the bike is in use, it ends up sloshing just over where the kickstart ratchet goes through into the kickstart housing and because the ratchet is a slide fit into the housing, the oil can slowly pass the ratchet shaft and therefore drip out of the housing and down onto your nice hot chrome exhaust pipe, leaving the tell tale sign of a burnt oil line. So to help with this, I sell either a complete new kickstart bearing housing, part number BK4, with oil seal fitted from new or the oil seal on it's own, part number LE431, where by you can machine your current housing in order for the oil seal to fit snuggly. If you don't have the use of a lathe then I can machine this for you if your housing is in good condition ie the kickstart crank return ramp on the housing isn't badly worn, allowing the kickstart crank to go past the 12 O'Clock position upon return or not pulling the crank out enough on it's return, causing the ratchet teeth to catch the 1st gear pinnion on the layshaft.

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Firstly I mount the housing in the chuck and clock the centre bore so that it is running concentrically

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This is then bored out to the correct width and depth for the oil seal to be pressed in

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With the oil seal pressed in, I check that the kickstart ratchet is still a nice slide fit through the oil seal, a little oil needs to be applied to the oil seal lip to help this.

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Once completed the housing is then ready to be assembled and fitted back onto the gearbox. You should now have one less oil leak on your Velo. One thing that I do get asked about is should there be a gasket behind the kickstart housing to seal against the gearbox, the answer is no, however I personally apply a small amount of clear thick grease to the mating face of the housing which also helps make a good seal between the housing and the gearbox front cover. At this stage it is also good practise to check the threads in the gearbox cover for the three fixing bolts as they get some stick over time and can become damaged. Helicoil kits at the ready!! All parts are available on the website. Please get in touch if you require any work to be carried out -

Tanks Classics Ltd is based on a passion for these amazing motorcycles. From building and restoring these bikes we have expanded into the business of supplying parts to enthusiasts and professionals alike who want the best for these machines that were produced by Veloce Ltd in Birmingham.

VAT : GB 314 3614 34
Our range of services enables us to offer a comprehensive and professional restoration and renovation for your motorcycle including spares for the wide range of Velocette motorcycles. Work includes full restoration of all parts, supply of new and used parts, vapour blasting, gearbox and engine work, professional paintwork and stove enamelling, magneto and dynamo overhaul and wheel building.

We also build made to order Clubmanised Velocette Venoms, taking your donor bike or supplying a donor bike and fully rebuilding the bike from the ground up, building the bike to your own specification. Please get in touch for further details.
If you have any questions please get in touch using the email with your enquiry, We will reply as soon as possible.

We are based in Cumbria, England

You can also telephone me at:
07870 762442

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+447870 762442
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